chemco handout

MASSA MARITIME ACADEMY “Creating Learning Experiences"

Specialized Training Program for Chemical Tankers Course (STPCTO)

COURSE HANDOUT

Great Eastern Summit, ‘A’ Wing, Plot No. 56, Sector 15, CBD Belapur, Navi Mumbai 400614

Tel 27562755 / 27574320 / 27574279 (Tel Fax 27574320 )

[email protected] / www.massamaritimeacademy.org

AOH Tel. 27562755 forwarded to Mobile No. 9820460595

MASSA MA R I T I M E A C A D E M Y INDEX

Rev No: 0 Date: 02/12/2005 Page No: 1 of 1 S.No. Description

1. Course Framework

2. Course Outline

3. Time Table

4. Specific Learning Objectives

5. Diagrams

6. Chemistry

7. Définitions

8. Glossary of Abbreviations

9. An Introduction to Sea Transport of Chemicals in Bulk

10. Hazards and Properties of Chemicals

11. Chemical Tankers

12. Safety in Chemical Tankers

MASSA M A R I T I M E A C A D E M Y COURSE FRAMEWORK

Rev No: 1 Date: 02/12/2005 Page No: 1 of 1

Scope: This course, called the Specialized Training Program for Chemical Tanker Operations Course is to intended to provides training for Masters, Chief engineers, Officers and any person with immediate responsibility for the loading, discharging and care in transit or handling of cargo. It comprises a specialised trainings programme appropriate to their duties, including chemical tanker safety, pollution prevention, operational practice and obligations under applicable laws and regulations. The course takes full account of section A-V/1 of the STCW Code adopted by the International Convention on Standards of Training, Certification and Watch keeping for Seafarers 1978, as amended in 1995.

Objective: Provided they hold an appropriate certificate and are otherwise qualified in accordance with regulation V/1-2.2 of the International Convention on Standards of Training, Certification and Watch keeping for Seafarers 1978, as amended in 1995, those successfully completing the course should be able to take immediate responsibility for loading, discharging and care in transit or handling of cargo on chemical tankers. Course Duration: Ten days (72 hours)

Course outline: Relevant extracts are enclosed.

Entry Standards: This course is open to seafarers who have completed a shore based fire-fighting training course approved by the Administration and who have relevant experience appropriate to their duties on chemical tankers, as stipulated in VI/1 as stipulated in STCW regulation V/1, paragraph 2.1, and sub-paragraphs 1.1 or 1.2.

Course Certificates: On successful completion of the course, a candidate will be issued a certificate, by the training institution, stating that the candidate has completed the course. 100 % attendance is required. Candidates unsuccessful in their internal assessment test, will be given the certificate of attendance only.

Teaching Equipment: The course will be conducted using lectures and presentations. White boards, OHP projector, OHP sheets, VCP with TV, computer with LCD projector will be used in lecture as per requirement of the lecturer. Assessment: The Institute will carry out assessment test of the students after completion of this course. Assessment shall consist of written exam, both objective and descriptive. Criteria for passing All candidates will be issued with a workbook through which candidates will be assessed continuously. At the end of the course they will be given final assessment and expected to answer all the questions, failing which he will be give additional instructions and will be reassessed before being issued with certificate of completion. Final assessment will be in the oral format.

MASSA M A R I T I M E A C A D E M Y COURSE OUTLINE

(AS PER META MANUAL APPENDIX M-V/1A) Rev No: 0 Date: 20/07/2004 Page No: 1 of 2

S No Subject Area Lecture

Hours 1 Introduction 3.0

1.1 1.2 1.3

Introduction – The Course Cargoes in chemical tankers Production and use of liquid chemicals

0.5 1.0 1.5

2 Chemistry and Physics (STCW Code, Section A-V/1 para 26)

6.0

2.1 2.2 2.3

Physical properties of cargoes Chemistry of cargoes Laboratory theory and practice

1.5 2.5 2.0

3 Hazards (STCW Code, Section A-V/1 para 27,32)

3.0

3.1 3.2 3.3 3.4 3.5

Health Hazards Hazards to the environment Reactivity hazards Flammability and Explosion Hazards First aid

1.0 0.5 0.5 0.5 0.5

4 Rules and Regulations (STCW Code, Section A-V/1 para 23)

8.0

4.1 4.2 4.3 4.4

International and national Codes and Regulations Bulk Chemical Codes Annex II of MARPOL 73/78 Certification and Surveys

1.0 1.5 4.5 1.0

5 Ship Design and Cargo Contamination (STCW Code, Section A-V/1 para 24,28)

3.0

5.1 5.2 5.3 5.4

Construction and equipment requirements Ship Arrangements Cargo containment Ship types and survival capacity

1.5 0.5 0.5 0.5

6 Cargo Handling Systems (STCW Code, Section A-V/1 para 30)

11.0

6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 6.9

Tanks, piping and valves Tanks materials and coatings Cargo tank vent systems Pumps and the unloading system Efficient stripping Cargo heating systems Tank-washing and slops-retaning systems Inert gas systems Instrumentation and auxiliary systems

1.0 1.0 0.5 4.0 1.5 0.5 1.0 1.0 0.5

MASSA M A R I T I M E A C A D E M Y COURSE OUTLINE

(AS PER META MANUAL APPENDIX M-V/1A) Rev No: 0 Date: 20/07/2004 Page No: 2 of 2

S No Subject Area Lecture

Hours 7 Safety and Pollution Prevention

(STCW Code, Section A-V/1 para 19,20) 12.0

7.1 7.2 7.3 7.4 7.5

Tank atmosphere evaluation Fire prevention and equipment Pollution prevention Protective and safety equipment Precautions concerning repair and maintenance

2.0 2.0 3.0 4.0 1.0

8 Cargo Handling and Ballast Operations Operations (STCW Code, Section A-V/1 para 18,19)

11.0

8.1 8.2 8.3 8.4 8.5 8.6 8.7 8.8

General Cargo Handling and ballast operations Cargo planning Procedures and preparation for loading Cargo measurement and calculation Cargo condition maintenance on passage and in port Procedures and preparation for unloading plan Unloading, stripping and pre wash operations with NLS Ballasting and deballasting

1.0 3.5 1.0 1.5 0.5 0.5 2.5 0.5

9 Tank cleaning operations (STCW Code, section A-V/1 para 19)

7.5

9.1 9.2 9.3 9.4

General tank cleaning operations Tank cleaning procedures and disposal of slops Gas freeing of cargo tanks Tests for cleanliness

1.0 4.5 0.5 1.5

10 Ship.Shore Interface (STCW Code, section A-V/1 para 19)

1.5

10.1 10.2

Liaison with terminals Shore recept ion facilities

1.0 0.5

11 Emergency Operations (STCW Code, section A-V/1 para 21)

3.0

11.1 11.2 11.3

Organisational structure and planning Alarms Emergency procedures

0.5 0.5 2.0

12 Assessment/Discussion 3.0 Total 72.0

M A S S A MA R I T I M E AC A D E M Y TIMETABLE


09:00

to 1100

11:00 to

11:10

11:10 to

12:40

12:40 to

13:10

13:10 to

14:40

14:40 to

14:50

14:50 to

17:00

MONDAY

1. Introduction 1.1. The Course 1.2. Cargoes in Chemical

Tankers 1.3. Production and use of Liquid

Chemicals

1.3. – contd – 2. Chemistry and

Physics 2.1. Properties &

Characteristics of chemical cargoes

2.1. – contd – 2.2. Chemistry of cargoes

2.3. Laboratory theory and practical

TUESDAY

2.3. - contd – 3. Hazard 3.1. Health Hazards 3.2. Hazards to the environment

3.3. Reactivity hazards 3.4. Flammability and

Explosion Hazards 3.5. First aid

4. Rules and Regulations

4.1. International and national Codes and Regulations

4.2. Bulk Chemical Codes

4.2.– contd – 4.3. Annex II of MARPOL

73/78

WEDNESDAY

4.3. - contd –

4.3. - contd – 4.4. Certification and Surveys

5. Ship Design and Cargo Contamination

5.1. Construction and equipment requirements

5.1.– contd – 5.2.Ship Arrangements 5.3.Cargo containment 5.4.Ship types and

survival capacity

THURSDAY 6. Cargo Handling Systems 6.1. Tanks, piping and valves 6.2. Tanks materials and

coatings

6.3. Cargo tank vent systems

6.4. Pumps and the unloading system

6.4. - contd – 6.4.- contd –

FRIDAY

6.5. Efficient stripping 6.6. Cargo heating systems

TEA

BR

EA

K

6.7. Tank-washing and slops-retaning systems

6.8. Inert gas systems

LUN

CH

6.8. - contd – 6.9. Instrumentation and

auxiliary systems

TEA

BR

EA

K

7. Safety and Pollution Prevention

7.1. Tank atmosphere evaluation

M A S S A MA R I T I M E AC A D E M Y TIMETABLE


09:00

to 1100

11:00 to

11:10

11:10 to

12:40

12:40 to

13:10

13:10 to

14:40

14:40 to

14:50

14:50 To

17:00

MONDAY 7.2. Fire prevention and

equipment

7.3. Pollution prevention

7.3. - contd –

7.4. Protective and safety equipment

TUESDAY

7.4. - contd –

7.5. Precautions concerning repair and maintenance

8. Cargo Handling and Ballast Operations Operations

8.1. General Cargo Handling and ballast operations

8.1. - contd – 8.2. Cargo planning

8.2. - contd –

WEDNESDAY

8.3. Procedures and preparation for loading

8.4. Cargo measurement and calculation

8.5. Cargo condition maintenance on passage and in port

8.6. Procedures and preparation for unloading plan

8.7. Unloading, stripping and pre wash operations with NLS

8.7. - contd – 8.8. Ballasting and

deballasting

THURSDAY

9. Tank cleaning operations 9.1. General tank cleaning

operations 9.2. Tank cleaning procedures

and disposal of slops

TEA

BR

EA

K

9.2. - contd –

LUN

CH

9.2. - contd –

TEA

BR

EA

K

9.3. Gas freeing of cargo tanks

9.4. Tests for cleanliness

09:00

to 1100

11:00 to

11:10

11:10 to

12:40

12:40 to

13:10

13:10 to

14:40

14:40 to

14:50

14:50 to

17:20

FRIDAY

10. Ship.Shore Interface 10.1. Liaison with terminals 10.2. Shore reception facilities 11. Emergency Operations 11.1. Organisational structure

and planning

11.2. Alarms 11.3. Emergency

procedures

12. Assessment/Discussion

12. Assessment/Discussion

MASSA M A R I T I M E A C A D E M Y SPECIFIC LEARNING OBJECTIVES

Rev No: 0 Date: 20/07/2004 Page No: 1 of 33 1. Introduction 1.1. The course 1.1.1. The background for and the purpose of the course as:

- The 1995 stcw convention calls for mandatory minimum requirements for training and qualifications of masters, officers and ratings on tankers

- The training is divided into two parts: o Tanker familiarization course: a basic safety training course for officers and

ratings assigned specific duties and responsibilities relating to cargo and cargo equipment on tankers covering at least the syllabus in the stcw code training can also be covered through at least three months of approved seagoing service

o A specialized chemical tanker training programme for masters, chief engineer officers, chief mates, senior engineer officers and any other person with immediate responsibility for loading, discharging and care in transit or handling of cargo in addition such personnel must have completed the tanker familiarization course and have experience appropriate to their duties on chemical tankers

1.1.2. The purpose of this course is to meet the requirements for specialized training given

in regulation v/1-2.2 of the stcw code 1.1.3. Officers and ratings on chemical tankers assigned specific duties and responsibilities

shall have completed an approved shore-based fire-fighting course 1.1.4. The importance of giving basic safety training to personnel who are unfamiliar with

chemical cargoes, in particular with respect to - Hazards to health - Fire hazards - Preventive measures - Remedial measures - Required performance

1.2. Cargoes in chemical tankers 1.2.1. A chemical tanker is primarily designed for the carriage of dangerous chemicals in

bulk 1.2.2. These chemicals are listed in the imo bulk chemical codes 1.2.3. In addition to the cargoes listed in the codes, chemical tankers may carry a wide

variety of other liquid products 1.2.4. Chemical tankers carry a wide range of products which would normally be considered

to be unrelated to chemicals 1.2.5. Examples of cargoes referred to under objective 1.2.4 as fruit juice, water, molasses,

animal and vegetable oils, clean petroleum products and lubricating oils 1.2.6. Clean petroleum products are those that have been produced in oil refineries and that

may be referred to as 'white oils' 1.2.7. White oils are the distilled lighter fractions derived from the refinery process, and

'black oils' are the heavier residues 1.2.8. Most of the petroleum product cargoes are transported in product tankers


Rev No: 0 Date: 20/07/2004 Page No: 2 of 33 1.2.9. Cargoes in chemical tankers may be divided into four groups as:

- Petrochemicals - Alcohols and carbohydrates - Vegetable and animal oils and fats - Acids and inorganic chemicals

1.2.10. 'Petrochemicals' is the collective name for organic chemicals derived from crude oil, natural gas or coal

1.2.11. The alcohols may be derived from hydrocarbons or produced by fermentation 1.2.12. Vegetable and animal oils and fats are products derived from seeds of plants and from

fat of animals and fish 1.2.13. What is meant by 'organic' and 'inorganic' chemicals 1.2.14. Acids may be organic or inorganic 1.3. Production and use of liquid chemicals 1.3.1. The number of liquid chemicals suitable for bulk transport in chemical tankers has

increased gradually over the years and is now counted by the hundreds 1.3.2. Most of the products shipped in chemical tankers are petrochemicals 1.3.3. Petrochemicals constitute the feedstock for plastics, synthetic rubber, synthetic fibres,

agricultural chemicals and detergents 1.3.4. The main sources of petrochemicals are the light gaseous hydrocarbons obtained

from processing crude oil in refineries and natural gas 1.3.5. Generally the processes for obtaining ethylene, propylene and butadiene gases from

crude oil and from natural gas 1.3.6. Some petrochemicals may be derived from coal 1.3.7. Generally the processes for obtaining chemicals from coal tar 1.3.8. Alcohols can be obtained from petroleum derivatives or by fermentation of

carbohydrates 1.3.9. Methanol is the most common alcohol carried as cargo in chemical tankers 1.3.10. Uses of alcohols in the chemical industry 1.3.11. Examples of vegetable and animal oils and fats 1.3.12. Uses of vegetable and animal oils and fats 1.3.13. The group of inorganic chemicals includes the strongest acids and bases transported in

chemical tankers 1.3.14. Examples of inorganic acids and bases 1.3.15. , In general terms, the origin and uses of inorganic acids and bases 1.3.16. Examples of organic acids 1.3.17. , In general terms the origins and uses of organic acids 2. Chemistry and physics 2.1. Physical properties of cargoes) 2.1.1. The following terms

- Of aggregation - Melting point - Boiling point - Partial pressure - Vapour pressure



- Volatility - Liquid density, specific gravity, litre weight - Vapour density - Viscosity, surface tension, adhesion, cohesion - Solubility, miscibility - Diffusion

2.1.2. Cargoes in chemical tankers are liquids having a vapour pressure not exceeding 2.8 bar absolute at a temperature of 37.8°c

2.1.3. The physical data of a liquid chemical, as given in the ics cargo data sheets, for example

2.2. Chemistry of cargoes 2.2.1. The structure of atoms 2.2.2. 'Atomic number' and 'atomic weight' 2.2.3. The periodic system and the periodic table 2.2.4. , In simple terms, a chemical reaction and the forming of molecules 2.2.5. A hydrocarbon molecule is characterized by the presence of carbon and hydrogen

atoms in various arrangements 2.2.6. Hydrocarbons with up to four carbon atoms in their molecules are gaseous at ambient

temperature and pressure 2.2.7. Hydrocarbons with from five to twenty carbon atoms are liquid at ambient conditions 2.2.8. Hydrocarbons with more than twenty carbon atoms in their molecules are solid at

ambient conditions 2.2.9. The structure of:

- A saturated hydrocarbon molecule - An unsaturated hydrocarbon molecule - An aromatic hydrocarbon molecule - A halogenated hydrocarbon molecule - An alcohol molecule

2.2.10. The chemical definition of an acid 2.2.11. The chemical definition of a base 2.2.12. The meaning of ph value 2.2.13. Identifies, from molecular drawings or models, some common chemicals by name 2.2.14. Many chemical cargoes are chemically reactive with themselves 2.2.15. Such reactions may result in: 2.2.16. The formation of larger molecules (polymerization) 2.2.17. The disintegration of molecules (decomposition) 2.2.18. The functions of inhibitors and catalysts 2.2.19. Inhibitors added to a liquid cargo may not inhibit reactions of the cargo vapour in the

ullage space 2.2.20. Extracts chemical data for a common cargo from the ics or other cargo data sheets 2.2.21. The meaning of the chemical data in 2.2.18


Rev No: 0 Date: 20/07/2004 Page No: 4 of 33 2.3. Laboratory theory and practical 2.3.1. The need of taking cargo samples and for chemical and physical analyses of cargoes 2.3.2. Demonstrates:

- The determination of cargo temperature - The determination of the cargo density - Use of a colour scale - A simple check for cargo residues trapped in rust, that are liable to contaminate

the next cargo - An 'acid wash' test

2.3.3. The permanganate time test 2.3.4. How the flashpoint of a liquid chemical is determined 2.3.5. The terms 'free fatty acid' (ffa) and 'acid value' 3. Hazards 3.1. Health hazards 3.1.1. The health hazards posed by cargoes in chemical tankers as:

- Toxicity - Asphyxia - Corrosivity

3.1.2. Toxic chemicals may enter the body by: - Inhalation - Ingestion - Skin contact

3.1.3. The harmful effect of a cargo depends on both its physical and its chemical properties 3.1.4. The inhalation hazard depends primarily on the volatility of the liquid 3.1.5. If swallowed, all poisons are dangerous 3.1.6. Some cargoes are irritants on human tissue 3.1.7. Strongly corrosive liquids destroy human tissue 3.1.8. Less corrosive liquids may only be irritating to the skin, but may cause serious

damage to eyes or to mucous membranes 3.1.9. Absorption of a cargo or of its vapour through the skin depends on the solvent nature

of the cargo 3.1.10. , In general terms, how cargo or cargo vapours may cause asphyxia 3.1.11. Some chemicals may evolve toxic vapours if they are in contact with other cargoes or

reactive agents 3.1.12. Toxic vapours may be generated from fire in certain chemicals 3.1.13. Toxic properties of inhibitors 3.1.14. Toxic properties of inert gas 3.1.15. General symptoms of poisoning 3.1.16. General symptoms of asphyxia 3.1.17. Information given in 'health data' columns of the ics or other cargo data sheets or cfr

title 46-150 3.1.18. The health hazard criteria as set out in the 18c code 3.1.19. Toxic cargoes should not be stowed in tanks adjacent to tanks containing edible

cargoes, and should be as far as possible from accommodation and from machinery spaces


Rev No: 0 Date: 20/07/2004 Page No: 5 of 33 3.2. Hazards to the environment 3.2.1. Some chemical cargoes pose a severe environmental hazard if released to the sea or to

the air 3.2.2. Marine pollution by chemicals may be caused by accidental and intentional discharge

into the sea of cargo, such as through: - Collisions and stranding - Lightening operations - Tank washing and line flushing - Deballasting - Overflow from tanks - Leaking hoses or loading arms - Equipment failure

3.2.3. The water pollution hazard criteria as listed in the 18c code 3.2.4. The air pollution hazard criteria as set out in the 18c code 3.2.5. The marine pollution hazard criteria as set out i the 18c code 3.2.6. Cargoes which represent a major pollution hazard should not be stowed in contact

with the ship's shell plating 3.2.7. International regulations for the control of marine pollution by cargoes from chemical

tankers are set out in annex ii of marpol 73/78 3.3. Reactivity hazards 3.3.1. A chemical cargo may react in a number of ways, such as:

- With itself - With air - With water - With another cargo - With other materials

3.3.2. Self-reaction and gives examples of cargoes that may self-react 3.3.3. Precautions against self-reaction 3.3.4. Reaction with air and gives examples of cargoesmay react with air 3.3.5. Precautions against reaction with air 3.3.6. Reaction with water and gives examples of cargoes that may react with water 3.3.7. Precautions against reaction with water 3.3.8. Cargo compatibility andchemical cargoes that are incompatible 3.3.9. Precautions against mixing of incompatible cargoes 3.3.10. Some cargoes may react with other materials, such as

- Tank materials and coatings - Gaskets - Cargo hoses - Cargo sample containers

3.3.11. Precautions against the reactions listed in objective 3.3.10 3.3.12. Reactivity data of chemicals are given in the ics, or other cargo data sheets or cfr46-

150


Rev No: 0 Date: 20/07/2004 Page No: 6 of 33 3.4. Flammability and explosivity hazards 3.4.1. The fire hazard of a cargo covered by the bulk chemical codes is defined by its

flashpoint, boiling point, flammability limits and auto-ignition temperature 3.4.2. Defines fiashpoint 3.4.3. Defines auto-ignition temperature 3.4.4. Flammable range and defines 'lfl' and 'ufl' 3.4.5. A cargo is flammable if it is capable of being ignited and of burning 3.4.6. Most chemical cargoes are flammable 3.4.7. It is not the liquid cargo that burns, but the vapours that are emitted from it 3.4.8. Generally, flammable vapours can ignite and will burn when mixed with air in certain

proportions 3.4.9. Certain cargo vapours can burn, if ignited, without being mixed with air 3.4.10. Combustion is a chemical reaction, andthe process of burning of hydrocarbons 3.4.11. The flammable range is different for different chemicals 3.4.12. The effect on the flammable limits of increasing and decreasing the amount of oxygen

within a space 3.4.13. Demonstrates use of a flammability chart 3.4.14. The ICS cargo data sheets, or CFR46-150 give the fire and explosion data for each

chemical listed 3.5. First aid treatment 3.5.1. First-aid procedures for accidents involving cargo are given in the cargo data sheets 3.5.2. Chemical tankers have medical first-aid equipment on board 3.5.3. The equipment referred to under objective 11.4.2 includes oxygen resuscitation

equipment and antidotes for the products to be carried 3.5.4. The master or responsible officer should be familiar with the use of medical first-aid

equipment 3.5.5. Professional medical treatment should be sought when in doubt, and always in cases

where casualties have been overcome by toxic and/or irritant vapours 3.5.6. The IMO medical first aid guide for accidents involving dangerous goods (MFAG)

gives information regarding emergency medical treatment 3.5.7. The MFAG gives detailed information about signs and symptoms, first aid and the

administering of antidotes 4. Rules and regulations 4.1. International and national codes and regulations 4.1.1. The most important of the rules governing the transport of liquid chemicals in bulk as:

- International conventions - National regulations - Classification society rules

4.1.2. Shipping activities are of international concern and that the international forum for maritime, and therefore shipping, matters is the imo

4.1.3. Imo has adopted safety and pollution conventions that affect ships


Rev No: 0 Date: 20/07/2004 Page No: 7 of 33 4.1.4. The conventions directly affecting the safe and pollution-free operations of chemical

tankers are: - SOLAS 1974/1995 - Marpol 73/78 and amendments - STCW 1995

4.1.5. Defines solas 1974/1995 as the international convention of the safety of life at sea, 1974/1995

4.1.6. Defines marpol 73/78 as the international convention for the prevention of pollution from ships, 1973/1978 and amendments

4.1.7. Defines stcw 1995 as the international convention of standards of training, certification and watchkeeping for seafarers, 1995

4.1.8. Countries which are party to the above conventions have the provisions of those conventions incorporated into their national laws and regulations

4.1.9. All chemical tankers and their personnel are affected by solas 1974/1995, marpol 73/78 and stcw 1995, either through their own national laws or through laws of the port state

4.1.10. Marpol 73/78 is an international convention which contains provisions for the control of both intentional and accidental pollution from ships

4.1.11. Marpol 73/78 has six annexes: Annex i regulations for the prevention of pollution by oil Annex ii regulations for the control of pollution by noxious liquid substances in bulk Annex iii regulations for the prevention of pollution by harmful substances carried by sea in packaged forms, or in freight containers, portable tanks or road and rail wagons Annex iv regulations for the prevention of pollution by sewage from ships Annex v regulations for the prevention of pollution by garbage from ships Annex vi regulations on the prevention of air pollution from ships

4.2. Bulk chemical codes 4.2.1. In order to provide an international standard of the safe carriage of chemicals in bulk

by ship, imo has developed the bulk chemical codes 4.2.2. Defines the codes referred to in objective 4.2.1 as:

- International code of the construction and equipment of ships carrying dangerous chemicals in bulk (ibc code)

- Code for the construction and equipment of ships carrying dangerous chemicals in bulk (BCH code)

4.2.3. The bulk chemical codes: - Amplify the provisions of chapter vii of solas 74 and annex ii of marpol 73/78 and

amendments - Were concerned initially with the crew safety and were later extended to include

pollution aspects - Provide an international standard of construction and equipment

4.2.4. The year of construction of a chemical tanker determines which code is applicable to the ship

4.2.5. Defines the terms 'new ship' and 'existing ship'


Rev No: 0 Date: 20/07/2004 Page No: 8 of 33 4.2.6. Chemical tankers may have to comply with the bulk chemical codes, either through

their national laws or through laws of the port state 4.2.7. Port state authorities may verify compliance with the imo conventions and codes 4.2.8. A ship which is constructed for carriage of both chemicals and liquefied gases in bulk

must comply with the requirements of both the bulk chemical codes and the gas carrier codes

4.3. Annex II of marpol 73/78 4.3.1. The principles underlying the protection of the marine environment from annex ii

substances as: - Identifying liquid substances carried in bulk which are harmful to the marine

environment, i.e. Noxious liquid substances (nls) - Ensuring that nls are carried in ships with increased survival capability - Ensuring that nls are unloaded to leave negligible quantities of residue - Stipulating conditions for the discharge of residues into the sea

4.3.2. In the implementation of those principles: - Nls have been divided into categories in accordance with the measure of harm

they can cause to the marine environment - There are requirements for the carriage of nls in a type 1,2 or 3 chemical tanker or

product tanker in accordancewith the measure of harm they can cause to the marine environment

- There are requirements for pumping and stripping capability and the prewashing of tanks carrying nls, depending on their category

- There are criteria for discharges into the sea that depend on the category of a nls and the sea area into which it is discharged

4.3.3. Defines 'harmful substance' 4.3.4. Annex ii substances have been divided into appendix ii and appendix iii substances 4.3.5. IBC codenls and other liquid substances carried in bulk 4.3.6. Defines 'noxious liquid substance' (nls) 4.3.7. The division of nls into categories a, b, c and d is for discharge purposes, with

category a posing the greatest and category d posing the least threat of harm to the marine environment

4.3.8. The determining factors in ascertaining a threat of harm to the marine environment are: - Degree of bioaccumulation - Aquatic toxicity - Hazard to human health - Damage potential to amenities

4.3.9. The factors referred to under objective 4.3.8 in a general way 4.3.10. , On the basis of those factors, hazard profiles are drawn up by gesamp for all liquid

substances carried in bulk 4.3.11. Defines gesamp as the joint group of experts on the scientific aspects of marine

pollution 4.3.12. The hazard profile of a substance 4.3.13. How hazard profiles are used in the categorization of substances 4.3.14. How hazard profiles are used in the assignment of ship type


Rev No: 0 Date: 20/07/2004 Page No: 9 of 33 4.3.15. Establishes the category of a substance given the hazard, profile of a substance and

the criteria for categorization 4.3.16. Establishes the ship type given the hazard profile of a non-dangerous nls and the

criteria for assigning ship type 4.3.17. Specific rules apply for categorization and for assignment of ship type in the case of

mixtures 4.3.18. The procedure by which liquid substances to becarried in bulk and not yet listed in

appendices ii or iii of annex ii are added to the list as: - Particulars of a substance to be supplied by means of a data sheet and submitted to

IMO - The hazard profile to be drawn up by gesamp - Categorization and assignment of ship type to be done by imo - Amendment to be made to appendices ii or iii of annex ii

4.3.19. The procedures for the provisional assessment of liquid substances carried in bulk 4.3.20. All NLS are included in chapters vi and 17, or vii and 18, respectively, of the bch and

IBC codes 4.3.21. All NLS of categories a, b and c are included in chapters vi and 17 of the codes 4.3.22. Depending on the date they were built, either the ibc or the bch code is mandatory for

ships carrying nls of categories a, b or c 4.3.23. Why category d substances may also be included in chapters vi and 17 of the codes 4.3.24. Why, with the entry into force of annex ii, certain substances (i.e. Cyclohexane,

toluene, xylenes) that were earlier transported in oil tankers have been listed in chapters vi and 17 of the codes

4.3.25. These may still be carried in oil tankers, subject to certain criteria 4.3.26. Defines such substances as 'oil-iike substances' 4.3.27. Criteria for determining if a substance is an oil-like substance 4.3.28. Oil-like substances, if carried as oil, come under the provisions of maapol 73n8 -

annex i 4.3.29. How the personnel of an oil tanker know which nls may be carried in the ship 4.3.30. Every ship carrying noxious liquid substances must be provided with a p & a manual 4.3.31. The arrangement of the manual 4.3.32. The p & a manual is approved by the administration and relates only to the ship for

which it is approved 4.3.33. Compliance with the procedures set out in the manual ensures compliance with the

annex ii requirements applicable to the ship 4.3.34. Why the manual is also of interest to port authorities 4.3.35. The relevance of the information in table 1 of the manual 4.3.36. The difference between entries in column 1 of table1 and the list of substances in the

certificate of fitness 4.3.37. The relevance of the information in table 2 of the manual 4.3.38. The flow diagrams of addendum a of appendix d of the standards for procedures and

arrangements for the discharge of noxious liquid substances 4.3.39. Identifies the cab 4.3.40.

- The CRB must be kept up to date by means of coded entries - Where coded entries are not possible, entries must be in language of the flag state,

or in english, or in french



- The above is necessary to allow inspection by port state authorities - The crb must be shown to the authorities if so requested - Copies may be made by authorities and must be signedfor as true copies - The crb is admissible as evidence in court - The crb must be retained on board for at least 3 years after the last entry

4.3.41. Using a description of shipboard operations, illustrates how correct and complete entries are made in a cab

4.3.42. Using a completed crb, verifies that all operational requirements have been observed, such as: - Unloading, stripping and prewash operations - Discharge into the sea of nls - Disposal of tank washings

4.4. Certification and surveys (0.5 hour) 4.4.1. For cargo ships, compliance with structural; requirements of solas 1974 is certified by

means of the cargo ship safety construction certificate 4.4.2. For cargo ships, compliance with equipment requirements of solas 1974 is certified by

means of the cargo ship safety equipment certificate and the cargo ship safety radio certificate

4.4.3. All chemical tankers that comply with the requirements for structure, equipment, fittings, arrangement a2-flg.4.1a and material set out in the bulk chemical codes are certified to 4.1 g by means of the certificate of fitness for the carriage of dangerous chemicals in bulk

4.4.4. The certificate of fitness has an attached list of the substances in chapter vi (bch code) or chapter 17 (ibc r3, r4 code) that a ship is permitted to carry

4.4.5. Certificate of fitness must also include chapter 18 substances of category d which ship is suitable to carry

4.4.6. All chemical tankers that also carry liquefied gas are issued with a certificate of fitness for the carriage of liquefied gases in bulk in addition to the certificate referred to in objective 4.4.3

4.4.7. Ships other than chemical tankers carrying nls in bulk must carry a pollution prevention certificate for the carriage of noxious liquid substances in bulk (nls certificate)

4.4.8. The ships referred to under objective 4.4.6 include: - Oil product tankers - Offshore supply ships - Dry-cargo ships with deep tanks

4.4.9. The flagare responsible for survey of ships, and for issuing certificates 4.4.10. The flagmay appoint other agencies or classification societies to carry out surveys and

to issue the certificates on their behalf 4.4.11. It is the responsibility of the master to keep the certificates valid and to call in survey

officers of the flag state in due course prior to the end of the period of validity of a certificate

4.4.12. The period of validity of a certificate of fitness is r4-pa. 1.5.2 not longer than 5 years 4.4.13. The following surveys are required for a valid certificate

- An initial survey to issue the first certificate



- A periodical survey to issue the subsequent certificates - Annual surveys within 3 months (before or after) of the anniversary dates of the

certificate - Intermediate surveys, which are more stringent surveys that take the place of

either the second or the third annual survey 5. Ship design and cargo containment 5.1. Construction and equipment requirements 5.1.1. The bulk chemical codes establish an international standard for the design,

construction and equipment of chemical tankers to minimize the risk to the ship, to its crew and to the environment

5.1.2. Chapter vi of the bch code and chapter 17 of the ibc code each give a summary of minimum requirements of products covered by the code

5.1.3. Products listed in chapter vii of the bch code and chapter 18 of the ibc code are products to which the codes do not apply

5.1.4. The lists may by used as a guide in considering bulk carriage of products whose hazards have not yet been evaluated

5.1.5. The entries used in the different columns of chapter vi of the bch code and chapter 17 of the ibc code required performance:

5.2. Ship arrangements 5.2.1. Segregation and separation of cargoes and spaces are fundamental to the safety of a

chemical tanker 5.2.2. Tanks containing cargo or residues of cargo that are subject to the codes should be

segregated from accommodation, service and machinery spaces and from drinking water and stores for human consumption

5.2.3. Segregation is done by means of cofferdams, void spaces, cargo pump-rooms, pump-rooms, empty tanks, oil fuel tanks or other similar spaces

5.2.4. Cargoes, residues of cargoes and mixtures containing cargoes which react in a hazardous manner with other cargoes should: - Be segregated from such other cargoes by means of a cofferdam, void space,

cargo pump-room, pump-room, empty tank or tank containing a mutually compatible cargo

- Have separate pumping and piping systems - Have separate tank-venting systems

5.2.5. Air intakes for accommodation, service and machinery spaces and control stations have to be at a minimum distance from ventilation outlets from cargo tanks and cargo-handling spaces

5.2.6. Access to accommodation or to the engine-room has to be a minimum distance of 3 metres from the forward division of accommodation

5.2.7. Windows and sidescuttles facing the cargo area and on the sides of the deck-houses within a distance of 3 metres should be of the fixed (non-opening) type

5.2.8. Wheelhouse windows and doors may be located within a distance of 3 metres from the end of the superstructure or deck-house facing the cargo area so long as they are designed that a rapid and efficient gas- and vapour-tightening of the wheelhouse can be ensured


Rev No: 0 Date: 20/07/2004 Page No: 12 of 33 5.2.9. Cargo pump-rooms or similar spaces normally entered during cargo-handling

operations. Should have a permanent ventilation arrangement that ensures sufficient movement of air through the spaces to avoid the accumulation of toxic or flammable vapours

5.2.10. The ventilation system of spaces referred to under objective 5.2.9 is normally of the extraction type and that extraction is possible both from above and below the floor plates

5.2.11. Electric motors used for driving fans should be placed outside the ventilation ducts 5.2.12. Ventilation fans should be of non-sparking construction and that spare parts should be

carried for each type of fan on board 5.2.13. Protection screens of not more than 13 mm square mesh should be fitted in outside

openings of ventilation ducts 5.2.14. Spaces in the cargo area that are not normally entered may be equipped with a

permanent or a portable ventilation system 5.3. Cargo containment 5.3.1. The design of cargo tanks should ensure good drainage and easy tank cleaning for

reasons such as: - Decreasing residues and thereby protecting the marine environment - Increasing cargo out-turn, leading to less disputes - Preventing cargo contamination when changing products

5.3.2. Defines the terms: - Independent tank - Integral tank - Gravity tank - Pressure tank

5.4. Ship types and survival capability 5.4.1. The bulk chemical codes divide chemical tankers into three categories, ship type 1,

ship type 2 and ship type 3, which reflect the dangerous and noxious properties of the cargoes to be carried

5.4.2. A type 1 ship is a chemical tanker intended for the transportation of products considered to present the greatest overall hazards and type 2 and 3 ships are for products of progressively lesser hazards

5.4.3. Type 1 ships are required for highly hazardous and/or noxious cargoes 5.4.4. The background for IMO'S grouping of ship types is:

- The ship's capability to survive damage caused by collision and stranding - The protection offered to cargo tanks against damage caused by stranding or by

collision 5.4.5. Ships subject to the codes should be capable of surviving specified extents of damage

in a condition of stable equilibrium satisfying the criteria specified in the code 5.4.6. The maximum extent of the assumed damage caused by collision or stranding is

specified in the code 5.4.7. A ship of type 1 should be able to survive the assumed damage anywhere in its length 5.4.8. A ship of type 2 and 3, depending on its length, should be able to survive the assumed

damage within specified areas of the ship's length


Rev No: 0 Date: 20/07/2004 Page No: 13 of 33 5.4.9. On ships of type 1 and 2, a cargo tank should be located inboard of b/15 or6 metres,

whichever is less, measured from the moulded line of the bottom shell plating at , the centreline

5.4.10. Furthermore, on ships of: - Type 1 , cargo tanks should be located b/5 or 11.5 metres (whichever is less)

inboard of the ship's side at right angles to the centreline at the level of the summer load line

- Type 2, cargo tanks should be located not less than 760 mm inboard of the ship's shell plating

5.4.11. For ships of type 3 there are no requirements for : the location of cargo tanks offering type 1 protection and cargo wing tanks offering type 2 or type 3 protection

6. Cargo-handling systems 6.1. Tanks, piping and valves 6.1.1. Generally, the requirements of cargo piping 6.1.2. Generally, cargo piping arrangements on chemical tankers in terms of:

- Pipe scantlings - Fabrication and joining - Flange connections - Test requirements - Arrangements - Valves - Hoses

6.1.3. Acceptable means of cargo segregation in terms of: - Separation by two valves - Spool-pieces

6.1.4. Commonly used types of valve on chemical tankers are: - Ball valves - Membrane valves - Gate valves - Butterfly valves

6.1.5. In general terms, the design of the valves listed in objective 6.1.4 6.1.6. Liquid and vapour hoses used for cargo transfer should be compatible with the cargo

and suitable for use at the cargo temperature 6.1.7. The bursting pressure for a new cargo hose should be at least 5 times the working

pressure of the hose 6.1.8. The cargo hoses should be inspected and pressure tested in accordance with national

regulations, normally once a year 6.1.9. The procedure for an annual test of the ship's cargo hoses 6.1.10. Generally, the maintenance and the correct handling of the ship's cargo hoses 6.2. Tank materials and coatings 6.2.1. All structural materials and linings used in cargo tanks, and the associated piping,

valves and pumps, must be suitable for the cargoes to be carried


Rev No: 0 Date: 20/07/2004 Page No: 14 of 33 6.2.2. Most chemical tankers have a number of coated tanks and a number of stainless-steel

tanks 6.2.3. Cargo piping, valves and pumps are normally made of stainless steel 6.2.4. Reasons for the use of stainless steel and coatings in cargo tanks 6.2.5. Clad' and 'solid' stainless steel 6.2.6. Generally, the composition of a typical stainless steel used on chemical tankers 6.2.7. Why stainless steel is 'stainless' 6.2.8. Generally, how stainless steel should be handled to avoid corrosion 6.2.9. Passivating' and 'pickling' of stainless steel 6.2.10. Hat stainless steel is resistant to most chemical cargoes 6.2.11. All non-stainless cargo tanks are coated 6.2.12. Main types of tank coatings as:

- Zinc silicate - Epoxy - Phenolics - Polyurethane

6.2.13. Chemical tankers dedicated to the carriage of highly corrosive cargoes may have their cargo tanks fitted with rubber linings

6.2.14. Each type of coating is resistant to groups of chemicals 6.2.15. In general terms, the limitations and possibilities of each type of coating 6.2.16. In general terms, the correct application technique for tank coatings 6.2.17. Generally, the maintenance of tank coatings 6.2.18. The 'coating resistance list' provided by the manufacturer should be strictly followed

when a cargo is to be loaded in a coated tank 6.3. Cargo tank vent systems 6.3.1. There are two types of ventilation systems for a cargo tank, 'open' and 'controlled' 6.3.2. The open cargo tank ventilation system 6.3.3. The controlled cargo tank ventilation system 6.3.4. All cargo tanks should be provided with a ventilation system appropriate to the cargo

being carried 6.3.5. The ventilation system of each tank is dimensioned to deal with all vapours that are

released by loading at normal rates 6.3.6. The tank ventilation system is designed so as to minimize the risk of accumulation of

cargo vapour in areas open to access by personnel 6.3.7. An open cargo-ventilation system should only be used for those cargoes that have a

fiashpoint above 60°c anddo not present a hazard when inhaled 6.3.8. A controlled cargo-ventilation system is to be used for cargoes other than those for

which open ventilation is permitted 6.3.9. The cargo venting system must be provided with readily renewable and approved

devices to prevent the passage of flame 6.3.10. Defines the devices referred to under objective 6.3.9 as: 6.3.11.

- Flame arresters - Flame screens - High-velocity vents

6.3.12. There are in-iine and end-of-line devices


Rev No: 0 Date: 20/07/2004 Page No: 15 of 33 6.3.13. Flame screens must not be used at vent outlets 6.3.14. With the aid of a drawing, the mode of operation of:

- A high-velocity valve - A flame arrester

6.3.15. General precautions regarding high-velocity valves 6.3.16. The purpose of the pressure/vacuum valve is to protect the cargo tank from too low or

too high pressure 6.3.17. With the aid of a drawing, the mode of operation of a pressure/vacuum valve 6.3.18. General precautions regarding pressure/vacuum valves 6.4. Pumps and unloading systems 6.4.1. Types of pump used on chemical tankers as:

- Centrifugal pumps - Piston pumps - Screw pumps - Eductors

6.4.2. The main cargo pumps fitted aboard chemical tankers are mainly of the centrifugal type

6.4.3. These centrifugal pumps may be of the deepwell types, of the submerged type or placed in a pump-room

6.4.4. The difference between a 'deepwell pump' and a 'submerged pump' 6.4.5. The construction and the operating principle of a centrifugal pump 6.4.6. The construction and the operating principle of a piston pump 6.4.7. The construction and the operating principle of an screw pump 6.4.8. The construction and the operating principle of an eductor 6.4.9. The benefits of using a centrifugal pump as a cargo pump as:

- Its simple construction - There being no valve in its construction - Its relatively small size, because the pump can operate at high speed - Its continuous pumping, and thereby no pulsation - There being no damage to the pump if the discharge valve gets closed during

pumping 6.4.10. Drawbacks of using a centrifugal pump as a cargo pump as:

- The difficulty of constructing a pump with a high differential pressure per stage - Its having high efficiency only within a limited field - Its normally not being self-priming - The backflow through the pump when it stops - The difficulty of pumping high-viscosity liquids

6.4.11. The drawback concerning a low differential pressure per stage may be solved by constructing pumps with several stages

6.4.12. The drawback concerning lack of self-priming may be solved either by submerging the pump in the liquid or by using priming equipment

6.4.13. The drawback concerning backflow may be solved by using non return valves 6.4.14. The drawback concerning the pumping of highly viscous liquids may be solved by

submerging the pump in the liquid, the thereby minimizing the loss of pressure at the pump's suction side


Rev No: 0 Date: 20/07/2004 Page No: 16 of 33 6.4.15. Deepwell pumps are commonly hydraulically driven 6.4.16. By the aid of a drawing, an open hydraulic system 6.4.17. By the aid of a drawing, an closed hydraulic system 6.4.18. Normally every cargo pump is supplied with a graph describing the pump's:

- Performance curve - Efficiency - Power consumption - NPSH

6.4.19. This graph is based on workshop tests 6.4.20. Total head' 6.4.21. The benefits of showing the pump's capacity as a function of total head 6.4.22. Design point' 6.4.23. NPSH' 6.4.24. Cavitation' 6.4.25. The curves listed under objective 6.4.18 and their relationship 6.4.26. The effects of cavitation 6.4.27. How a combined pump characteristic is constructed when running pumps in parallel

that have the same suction and discharge condition 6.4.28. The dangers connected with running two or more pumps in parallel if the

characteristics or speeds are not exactly the same 6.4.29. The actual discharge rate depends on:

- The pressure in the shore tank - The static back-pressure - The dynamic back-pressure

6.4.30. Static back-pressure' 6.4.31. Dynamic back-pressure' 6.4.32. Factors having influence on dynamic back-pressure 6.4.33. Methods of automatic control and protection of cargo pumps 6.4.34. Correct and safe handling of a deepwell pump 6.4.35. With the aid of a drawing, a stripping arrangement using an eductor 6.4.36. With the aid of a drawing, a stripping arrangement using a deepwell pump designed

for stripping 6.5. Efficient stripping 6.5.1. What the pumping and stripping system must be capable of doing when a tank is

certified to carry: - Category a substances - Category b substances - Category c substances - Category d substances

6.5.2. The test for verifying whether tanks can carry substances of category b and of category c

6.5.3. Parameters which may influence the result of the test referred to under objective 6.5.2 6.5.4. Why subsequent unloading and stripping operations must take account of those

parameters


Rev No: 0 Date: 20/07/2004 Page No: 17 of 33 6.5.5. The effects of the viscosity and melting point of a product on the effectiveness of the

stripping system 6.5.6. At which viscosities the stripping system is not considered to be efficient enough for

substances of category b and c, both outside and within special areas 6.5.7. The relationship between the melting point of a substance, its unloading temperature

and the possibility of efficient stripping 6.5.8. With the aid of drawings,the operating principles of efficient stripping systems:

- Using compressed gas - Not using compressed gas

6.5.9. Examples of ships carrying substances of category b and c which do not need to be fitted with an efficient stripping system

6.6. Cargo heating systems 6.6.1. Some cargoes, having a high melting point, must be heated to prevent them from

solidifying 6.6.2. The heating medium may be steam, water or thermal oils 6.6.3. With the aid of a drawing, a cargo heating system that uses heating coils fitted inside

the cargo tanks 6.6.4. With the aid of a drawing, a cargo heating system that uses a heat exchanger placed

outside the cargo tank 6.6.5. Generally, the imo requirements concerning cargo heating systems t 6.7. Tank-washing and slops-relating systems 6.7.1. The type of cleaning system on chemical tankers depends on the ship's cargo and its

trade 6.7.2. A sophisticated cleaning system commonly consists of the following main

components: - Tank cleaning pump - Tank cleaning heat exchanger - Tank-washing machines - Water distribution pipeline

6.7.3. The tank cleaning heat exchanger and the tank cleaning pump must be of approximately the same capacity

6.7.4. The tank-washing machines are either portable or fixed 6.7.5. A tank-washing and slops-retaining system 6.7.6. With the aid of a drawing, the construction of a tank-washing machine 6.8. Inert gas systems 6.8.1. Defines 'inert gas' and lists, generally, the requirements of imo concerning

environmental control 6.8.2. Inert gas is used in cargo tanks:

- To protect the cargo from polymerization, oxidation and humidity f - To replace air, thereby preventing fire and explosion .

6.8.3. Different methods of producing and supplying inert gas 6.8.4. Why nitrogen is used instead of inert gas 6.9. Instrumentation


Rev No: 0 Date: 20/07/2004 Page No: 18 of 33 6.9.1. Electrical installations on chemical tankers that carry flammable products should be

such as to minimize the risk of fire and explosions 6.9.2. The different types of electrical equipment approved for operation in gas-hazardous

locations 7. Safety and pollution prevention 7.1. Tank atmosphere evaluation 7.1.1. Information to be obtained during tank atmosphere evaluation as:

- Type of atmosphere (constituents) - Flammability - Toxicity/oxygen deficiency - Reactivity

7.1.2. Tank atmosphere evaluation is to be carried out: - Prior to entry of personnel into a tank - During inerting, gas-freeing and purging operations - To establish a gas -free condition - As a quality control before loading

7.1.3. The atmosphere in a cargo tank or enclosed space may be dangerous due to flammability, toxicity and/or lack of oxygen

7.1.4. No personnel should enter or work in a tank or an enclosed space unless safe working conditions are created

7.1.5. It is the responsibility of the master or officer on duty to ensure that safe working conditions are created

7.1.6. Tank atmosphere evaluation is essential to safe working conditions 7.1.7. As a rule, a tank or enclosed space should not be entered 7.1.8. Precautions for safe working conditions should be observed when entry is necessary 7.1.9. Precautions for work in enclosed spaces 7.1.10. Procedures for testing of tank atmosphere with regard to:

- Oxygen content - Flammable vapours - Toxic vapours

7.2. Fire prevention and equipment 7.2.1. The elements necessary for a fire andthe fire triangle 7.2.2. The principles of fire prevention 7.2.3. Possible ignition sources and ways of excluding them from gas-dangerous places 7.2.4. Ignition can occur when an ignition source with a temperature at or above the

autoignition temperature of a cargo is introduced into the vapour phase of a flammable cargo

7.2.5. Sources of emission of flammable cargo vapour as leaks from pumps, flanges, hoses, relief valves, etc

7.2.6. Most ignition sources on board have a higher temperature than the autoignition temperature for most chemical cargoes

7.2.7. Temperatures of common ignition sources as: - The flame of a match, 1100°c



- Electrical spark, 1100°c - The light of a cigarette, 300 to 800°c

7.2.8. The autoignition temperature of chemical cargoes may be as low as 30°c (for phosphorus)

7.2.9. Methods of controlling a fire, in general, as:

- Removal of oxygen - Cutting off the supply of fuel - Removing the source of heat by cooling - Inhibiting the burning process

7.2.10. Some liquid chemicals have unusual properties with regard to fire and fire-fighting compared with hydrocarbons

7.2.11. The properties referred to under objective 7.2.10 7.2.12. Chemical tankers are fitted with a fixed foam system for fire-fighting that is capable

of delivering foam to the entire cargo area, i.e. To the deck area as well as to any cargo tank

7.2.13. Chemical tankers are fitted with a fixed fire- extinguishing system in cargo pump-rooms

7.2.14. Extinguishing agents for systems referred to under objective 7.2.13 are normally a halon or carbon dioxide, but water or high-expansion foam may be used in certain vessels

7.2.15. The fire-extinguishing media that are considered to be suitable for specific cargoes are listed in chapter 17 of the IBC code

7.2.16. Water as a fire-fighting agent in terms of: - It is readily available - It is an excellent cooling agent - It can be used in spray form against limited oil fires - It may be used in the form of spray/fog to create a screen ; for protection of fire-

fighters when they are approaching a ;fire - It should not be directed as a jet into burning oils or fats - It should not be used against fires involving cargoes that react dangerously with

water - It should not be directed towards electrical equipment

7.2.17. Foam as a fire-fighting agent in terms of: - It should be of a type suitable for fighting fires in chemicals - It has good smothering effect on flames - It is less effective against fires in chemicals that have a low flashpoint - It has limited heat-absorbing effect - It should not come in contact with live electrical equipment

7.2.18. Dry chemical powder as a fire-fighting agent in terms of: - It has a good smothering effect on flames - It has an inhibiting effect - It can be used in electrical plants - It is not toxic - It has a low cooling effect - It should not be used on electronic instruments, control panels, etc.

7.2.19. A halon as a fire-fighting agent in terms of:



- It has an inhibiting effect on flames - It can be used on fires in electrical equipment and instruments - It should be used in conditions where it is not diffused, i.e. In enclosed spaces - It depletes the ozone layer

7.2.20. Carbon dioxide as a fire-fighting agent in terms of: - It is an excellent smothering agent - It can be used on fires in electrical equipment and instruments - It should not be injected into explosive atmospheres, as it may generate static

electricity - Personnel must have left the space into which carbon dioxide is to be injected

7.2.21. The items of equipment of a fireman's outfit 7.2.22. All fire-fighting appliances should always be kept in good order and ready for use 7.2.23. Prior to commencing cargo transfer, the ship's fire-fighting equipment should be made

ready and the international shore connection should be at hand 7.2.24. The importance of fire-prevention procedures, andprecautions with regard to:

- Smoking - Electrical equipment - Tools - Flame screens - Bonding - Static electricity - Electrical storms - Auto ignition - Spontaneous combustion

7.3. Pollution prevention 7.3.1. Defines pollution as inconvenience or damage, caused by human activities, to

humans, animals, plants and to our environment as a whole by the spreading of compounds to air, water or land

7.3.2. Deliberate, negligent or accidental release of chemicals from chemical tankers each constitute a serious source of pollution

7.3.3. Pollution risks from chemical tankers are minimized through regulations for the construction and equipment of such ships and through regulations for the handling of noxious liquid substances and their residues

7.3.4. Examples of requirements which minimize pollution risks with regard to construction and equipment as: - Construction and location of cargo tanks - Cargo pumps and pipings - Overflow controls - Vapour emission controls

7.3.5. Examples of requirements which minimize pollution with regard to the handling of noxious cargoes as: - Categorization of cargoes - Stripping requirements - Tank washing requirements



- Discharge requirements - Reception facilities

7.3.6. Pollution from cargoes can be minimized through using correct working routines and by following the applicable pollution regulations

7.3.7. In the event of cargo spillage, operations should be suspended immediately and the spillage dealt with promptly

7.3.8. Harbour authorities and/or shore installation and nearby ships should be warned of any hazard in connection with cargo spillage

7.3.9. The master or duty officer in charge of any operation involving cargo, ballast or bunkers should know the applicable pollution regulations and ensure they are not violated

7.3.10. 'Discharge' 7.3.11. The principles underlying the protection of the marine environment against

operational discharges of nls as: - Reducing residues after unloading to acceptably small quantities - Ensuring their effective mixing with seawater when such quantities or residues are

discharged into the sea - Subjecting discharges to limitations, such as a minimum distance from the land

and a minimum water depth 7.3.12. The principles outlined in objective 7.3.11 are achieved in different ways for different

categories of substances 7.3.13. More stringent discharge criteria apply for special areas 7.3.14. Special area' 7.3.15. Special areas include the antarctic area, the baltic sea area, mediterranean sea area,

black sea area, the gulf area, gulf of aden area, red sea area and north-west european waters

7.3.16. The discharge provisions for category a substances 7.3.17. The discharge provisions for category b substances 7.3.18. The discharge provisions for category c substances 7.3.19. The discharge provisions for category d substances 7.3.20. The discharge provisions for category a substances 7.3.21. The discharge provisions for category b substances 7.3.22. The discharge provisions for category c substances 7.3.23. The discharge provisions for category d substances 7.3.24. Compared with category a and d substances, the discharge into the sea of category b

and c residues is complicated by the need to: - Verify that the quantity of the residue is within prescribed limits - Ensure that the concentration of residue in the wake of the ship does not exceed

the prescribed limits 7.3.25. When, as for substances of category a, residues of category 8 and c are reduced to

small or negligible quantities after unloading: - The same provisions for discharge into the sea apply as for category a residues - No calculations are necessary to establish the quantity and the concentration of

residue in the ship's wake 7.3.26. The discharge provisions referred to under objective 7.3.25 7.3.27. The small or negligible quantities of residue referred to under objective 7.3.25 can be

achieved through:



- The efficient stripping of cargo tanks - Applying a prewash after unloading, with subsequent disposal of the prewash

slops to a shore installation 7.3.28. The meaning of efficient stripping and prewashing 7.3.29. In order to be able to reduce the amounts of residues, category 8 substances with a

melting point of 15°c or higher must be carried in tanks which: - Are not adjacent to the ship's shell plating - Can be heated

7.3.30. Residues can, under certain conditions, be removed by ventilation 7.3.31. Discharges of residues of nls should normally be made through an underwater

discharge outlet 7.3.32. Why such discharges should not penetrate the ship's boundary layer 7.3.33. The measures to be taken to ensure that discharges do not penetrate the ship's

boundary layer 7.3.34. The detrimental effects which residues within the boundary layer can have for the

ship's inlet openings and what operational precautions can be taken 7.4. Protection and safety equipment 7.4.1. The requirements for and the standard of protection and safety equipment are laid

down by international and national regulations 7.4.2. All protection and safety equipment should be regularly inspected and kept ready for

immediate use 7.4.3. Regulations call for regular training and drills in the use of safety equipment 7.4.4. Equipment required on chemical tankers for gas measurements 7.4.5. The function and demonstrates the calibration of gas-measuring equipment 7.4.6. Acting as a member of a group, carries out evaluation of a simulated tank atmosphere

with regard to: - Oxygen content - Flammability. - Toxicity

7.4.7. The items constituting protection equipment of crew members engaged in cargo operations

7.4.8. The respiratory and eye protection needed for the purpose of an emergency escape 7.4.9. The different types of respiratory protection filters and demonstrates their use 7.4.10. Self-contained breathing apparatus and demonstrates their use 7.4.11. The parts in the complete set of safety equipment 7.4.12. The use, storage and maintenance of safety equipment and of protective equipment 7.4.13. Decontamination showers and eyewash should be kept operable at all times and at all

ambient conditions 7.4.14. Explain the medical first-aid equipment for chemical tankers 7.4.15. Acts as a member of a group and carries out team exercises using:

- Tank and pump-room evacuation equipment - First-aid and resuscitation equipment

7.5. Precautions concerning repair and maintenance 7.5.1. Cold work, hot work, enclosed space entry, electrical isolation and other permits

should be obtained before work commences


Rev No: 0 Date: 20/07/2004 Page No: 23 of 33 7.5.2. Work on pipelines, valves or pumps should only be permitted when item is:

- Detached from the system by cold work - Remaining system is blanked off - Item is cleaned and gas freed

7.5.3. Great care should be taken due to possible remaining cargo residues 7.5.4. Work on control systems may affect safe cargo handling procedures 8. Cargo handling and ballast operations 8.1. General 8.1.1. The master, or a qualified officer appointed by him, is responsible for the safety of the

vessel and all cargo and ballast operations 8.1.2. The officer responsible for cargo and ballast operations should be familiar with the

arrangement of tanks, lines and pumps and should supervise all operations 8.1.3. The responsible officer should be present at all times during operations 8.1.4. The importance of function tests of all equipment in the cargo system prior to any

cargo operations 8.1.5. Details of emergency procedures for each cargo being handled should be available to

all concerned 8.1.6. Equipment for personal protection should be used when handling dangerous cargoes 8.1.7. Safety and first-aid equipment should be ready for immediate use 8.1.8. All cargo and ballast operations must be done in accordance with regulations 8.1.9. The master should ensure proper liaison between ship and terminal prior to and during

cargo-transfer operations 8.1.10. All cargo or ballast operations should be recorded in the ship's log 8.1.11. All cargo or ballast operations involving substances in categories a, b, c and d are also

to be recorded in the cargo record book 8.1.12. The provisions of annex ii of marpol with respect to unloading, stripping, prewashing

and ballast operations in relation to nls must be complied with 8.1.13. Compliance with annex ii of marpol 73178 is ensured by complying with the ship's

procedures and arrangements manual 8.2. Cargo planning 8.2.1. Thorough cargo planning is essential to safe and correct cargo handling 8.2.2. Main points in cargo planning as:

- Cargo requirements - Cargo compatibility - Resistance list of tank material/coating - Tank cleanliness - Tank capacity - Cargo handling - Loading rotation - Discharging rotation

8.2.3. Given the names of some common chemicals to be loaded, identifies the minimum requirements set out in chapter 17 of the 18c code

8.2.4. Identifies the physical and chemical properties of the cargoes named in objective 8.2.3 by using the cargo data sheets or cfr46-150


Rev No: 0 Date: 20/07/2004 Page No: 24 of 33 8.2.5. With the aid of a cargo compatibility chart, determines whether or not a cargo can be

loaded adjacent to another cargo 8.2.6. With the aid of a tank lining guide, determines which type of tank material or coating

the different cargoes require 8.2.7. Generally, the requirements for tank cleanliness prior to loading of some common

cargoes 8.2.8. Cargo-handling procedures such as:

- Heating - Padding - Blanketing

8.2.9. Heated cargoes should not be loaded adjacent to polymerizable or inhibited cargoes 8.2.10. Heated cargoes should not be loaded adjacent to highly volatile cargoes 8.2.11. Toxic cargoes should not be stowed adjacent to edible cargoes 8.3. Procedures for loading and preparations for loading 8.3.1. Any cargo to be loaded should be indicated in the shipping documents by the correct

technical name 8.3.2. Cargo information giving the necessary data for its safe carriage should be on board

and available to all concerned 8.3.3. In general terms, the information required for the safe carriage of liquid chemicals 8.3.4. The cargo should be refused if sufficient cargo information is not available 8.3.5. The bulk chemical codes provide operational requirements for cargoes covered by

them 8.3.6. General precautions to be taken prior to loading 8.3.7. The loading operations should be preplanned and the cargoes should be stowed

according to a stowage plan prepared before loading - 'Loading over the top' - 'Drop line loading' - 'Loading through pump-room'

8.3.8. Cargoes which are flammable or produce harmful vapours should not be loaded over the top

8.3.9. Precautions prior to loading over the top 8.3.10. The atmosphere in cargo tanks and, in some cases, in the spaces surrounding cargo

tanks may require special attention prior to loading . - Inerting - Padding - Drying

8.3.11. The need for taking cargo samples andgeneral procedures for sampling a cargo in loading ports in terms of: - A manifold sample - A tank sample when the liquid level is approximately 30 cm - A tank sample when the loading has been completed

8.3.12. How cargo samples should be handled and stowed 8.3.13. Harmful cargo vapours displaced from tanks during loading should be vented to

atmosphere through the vent system and that tank hatches should be closed 8.3.14. Local regulations may require cargo vapours to be returned to shore through a 'vapour

return line'


Rev No: 0 Date: 20/07/2004 Page No: 25 of 33 8.3.15. General precautions to be taken during the loading b1 operation . 8.3.16. General precautions to be taken during lightening operations 8.3.17. General precautions to be taken after loading has been completed 8.4. Cargo measurement and calculation 8.4.1. The quantity of a cargo required to be carried in a type 1 ship should not exceed 1250

m3 in anyone tank 8.4.2. The quantity of a cargo required to be carried in a type 2 ship should not exceed 3000

m3 in anyone tank 8.4.3. Cargo tanks should e so loaded as to avoid the tank becoming liquid-full during the

voyage, having due regard to the highest temperature that the cargo may reach 8.4.4. The codes provide for special requirements for. The maximum tank filling limits for

cargoes with a vapour pressure greater than 1.013 bar absolute at 37.8°c 8.4.5. 'Sounding' and 'ullage' 8.4.6. Units used in the international system of units and defines:

- Volume - Density - Mass

8.4.7. Defines: - Specific gravity - Litre weight - Weight in air - Weight in vacuum

8.4.8. Other units of measurement that are commonly used in cargo calculations 8.4.9. With the aid of the ullage tables of a certain tanker and the api-ip-astm tables, corrects

measurements of liquid level (ullage) and calculates cargo quantity (mass) in metric tons, given: - Type of cargo - Tank gauge reading - Cargo temperature - Cargo liquid density at 15°c

8.4.10. Demonstrates use of the density correction factor 8.4.11. Converts mass to 'weight in air' 8.4.12. Fills in a cargo report 8.5. Cargo conditioning during transport 8.5.1. The term 'cargo conditioning' refers to the following general requirements of the

trade: - The cargo quantity is maintained without undue losses during passage - The quality of the cargo is kept unchanged - The cargo temperature is maintained or changed as required and according to the

shipper's instructions - Inerting, padding or drying conditions are maintained as required

8.5.2. In general terms, how the requirements listed in objective 8.5.1 may be covered by a vessel's personnel

8.5.3. In general terms, the transport requirements for vegetable and animal oils and fats


Rev No: 0 Date: 20/07/2004 Page No: 26 of 33 8.6. Unloading plan and procedures 8.6.1. Unloading operations should be preplanned and the different cargo parcels discharged

according to the plan 8.6.2. General precautions prior to unloading 8.6.3. All pumps, valves and instrumentation should be function tested prior to unloading 8.6.4. How drying or inerting requirements for the tank atmosphere are dealt with during

unloading 8.6.5. The need for taking cargo samples andthe general procedure for sampling a cargo in

the unloading port in terms of: - Taking a tank sample prior to unloading - Taking a manifold sample when unloading commences

8.6.6. General precautions during unloading 8.6.7. The vessel should be unloaded so that its trim enables the best possible drainage of

cargo tanks 8.6.8. For cargoes that have a high vapour pressure it may be necessary to assist the

unloading and drainage by pressurizing the cargo tank 8.6.9. When pressurizing is done, the tank pressure must be carefully monitored and must

not exceed the design pressure 8.6.10. The means of pressurization depends on the properties of the cargo, such as its:

- Flammability - Reactivity

8.6.11. Precautions after unloading is completed 8.7. Unloading, stripping and prewash operations with NLS 8.7.1. The procedures required after the completion of unloading a tank containing category

a substances 8.7.2. The procedures after unloading if measurement of the concentration of residue in the

tank washing effluent is not practicable 8.7.3. The conditions for exemption from the above procedures for substances which are not

suitable for ventilation procedures 8.7.4. After application of the washing procedures referred to under objectives 8.7.1 and

8.7.2, a tank may be further washed or ballasted 8.7.5. Under what conditions the subsequent wash water or ballast from a tank may be

discharged into the sea 8.7.6. Under what conditions an exempted tank, referred to under objective 8.7.3, may be

ballasted or washed 8.7.7. The different in procedures when the ship unloads within a special area. 8.7.8. Defines:

- High-viscosity substance - Solidifying substance

8.7.9. The procedures required after completion of unloading a tank of low-viscosity non-solidifying substances of category b

8.7.10. The procedures required after completion of unloading a tank of high-viscosity or solidifying substances of category b

8.7.11. The conditions for exemption from the procedures referred to under objective 8.7. 10 for substances which are not suitable for ventilation procedures


Rev No: 0 Date: 20/07/2004 Page No: 27 of 33 8.7.12. After application of the procedures referred to under objectives 8.7.9 and 8.7. 10, a

tank may be f~rther washed or ballasted 8.7.13. Under what conditions the subsequent wash water or ballast from a tank may be

discharged into the sea 8.7.14. Under what conditions an exempted tank, referred to under objective 8.7. 11 , may be

washed or ballasted 8.7.15. The difference in procedures when the ship unloads within a special area. 8.7.16. Defines:

- High viscosity substance o Outside special areas o Within special areas - Solidifying substance

8.7.17. The procedures required after completion of unloading a tank of low-viscosity non-solidifying substances of category c

8.7.18. The conditions for exemption from the above procedures for substances which are not suitable for ventilation procedures

8.7.19. After application of the washing procedures referred to under objectives 8.7.1 and 8.7.2, a tank may be further washed or ballasted

8.7.20. Under what conditions the subsequent wash water or ballast from a tank may be discharged into the sea

8.7.21. Under what conditions an exempted tank, referred to under objective 8.7.3, may be ballasted or washed

8.7.22. The different in procedures when the ship unloads within a special area.: 8.7.23. The procedures required after the completion of unloading substances of category d 8.7.24. Ballast containing not more than 1 ppm of residue of a substance of category b or c 8.7.25. When ballast water may be expected to contain no more than 1 ppm of residue 8.7.26. Under what conditions ballast water that contains 1 ppm of residue may be discharged

into the sea 8.8. Ballasting and deballasting 8.8.1. The ship should at all times during loading and unloading operations be stable and in

good trim, to allow for an emergency departure if necessary 8.8.2. The stability of most chemical tankers is good in normal conditions, due to the large

number of relatively small cargo tanks 8.8.3. Chemical tankers may have to undertake ballasting or deballasting during cargo

operations to obtain adequate trim and prevent undue list 8.8.4. Chemical tankers may be equipped with segregated ballast tanks (sbt) 8.8.5. Lines, pumps and equipment serving s8t are independent of similar equipment serving

cargo tanks 8.8.6. Cargo tanks may be used for ballast andgeneral precautions that should be taken when

ballasting a cargo tank 8.8.7. The ballasting or deballasting of cargo tanks after they have contained a nls should be

done in accordance with the ship's p & a manual, thereby ensuring compliance with annex ii of marpol 73178

8.8.8. The responsible officer should see to it that the distribution of cargo and ballast at no time creates excessive stress on the ship's hull


Rev No: 0 Date: 20/07/2004 Page No: 28 of 33 8.8.9. Why stability problems may occur in chemical tankers with u-shaped ballast tanks

and/or with tweendeck ballast tanks 8.8.10. Generally, the effect of free surface in cargo tanks and ballast tanks 8.8.11. Ballast operations in port should be in compliance with local regulations 9. Tank-cleaning operations 9.1. General 9.1.1. On chemical tankers, gas-freeing and tank cleaning may take place concurrently with

cargo operations 9.1.2. Tank-cleaning, gas-freeing and slops-handling operations should be preplanned and

done in accordancewith prevailing safety regulations and pollution regulations 9.1.3. The necessity of adequate shore reception facilities for tank washings 9.1.4. A responsible officer who is familiar with the arrangement of tanks, lines and pumps,

must supervise all tank-cleaning and gas-freeing operations 9.1.5. The officer of the watch should be fully informed and familiar with the preplanned

work programme 9.1.6. The master should ensure proper liaison between ship and terminal prior to and during

operations 9.1.7. Tank cleaning in chemical tankers may be carried out in the following atmospheres:

- Undefined - Too rich - Too lean - Inerted

9.1.8. The atmosphere referred to under objective 9.1.7 andgeneral precautions for tank cleaning in port and at sea

9.2. Tank-cleaning procedures and disposal of slops 9.2.1. Reasons for tank cleaning as:

- Rules and regulations - Requirements of tank cleanliness for cargo to be loaded - Ballasting of cargo tanks - Maintenance of cargo tanks and equipment - Safe entry of personnel into tanks and repairs

9.2.2. For tank-cleaning operations involving nls, the ship's p & a manual must be consulted 9.2.3. Important factors to be considered in the planning of a tank-cleaning programme as:

- What was the last product carried? - What is the next product to be carried? - Do the washings require shore reception facilities? - In port, what are local regulations? - What other environmental aspects must be considered?

9.2.4. Cargo tanks should be properly drained prior to their cleaning 9.2.5. Measures to be taken to achieve the best possible ,drainage 9.2.6. Phases in a tank-cleaning operation as:

- Prewash - Main wash - Fresh water rinse



- Gas-freeing - Drying - Inspection/testing

9.2.7. For some noxious cargoes, pollution regulations call for either prewashing or efficient stripping

9.2.8. The requirements for cleanliness of a cargo tank to ensure there is no contamination of the cargo vary with the product

9.2.9. Washing procedures for meeting the required degree of cleanliness are described in different tank cleaning guides, which should be available on board

9.2.10. Most cleaning operations can be carried out by water washing only 9.2.11. Detergents are added to the washing water in some cases 9.2.12. Cargo tanks containing residues that react with water are washed with other liquids,

i.e. Solvents 9.2.13. The resistancefor tank coating should be consulted in connection with tank cleaning

with regard to chemical resistance and temperature 9.2.14. With the aid of a tank cleaning guide, sets up a plan for the cleaning of cargo tank,

given: - The cargo to be cleaned from (last cargo) - The cargo to be cleaned for (next cargo) - The tank materiavcoating

9.2.15. - What a prewash is - What it is meant to achieve - How it is done

9.2.16. Which products necessitate a prewash 9.2.17. A prewash is an alternative procedure for complying with the discharge provisions of

substances in category a 9.2.18. Prewash requirements stipulate:

- The number of washing machines to be used - The duration of the wash, related to the cycles of the washing machines - The temperature of the washing water

9.2.19. The duration of the prewash only applies when slops are continuously pumped out 9.2.20. How the inability to pump continuously affects the duration of the prewash 9.2.21. How the properties of a product affect the prewash 9.2.22. When hot water must be used for prewashing 9.2.23. Normally, a prewash must be carried out in the unloading port 9.2.24. Exceptions to that rule 9.2.25. When prewash slops may be taken to sea for discharge 9.2.26. Prewashing constitutes a measure aimed at the protection of the marine environment

and is unrelated to commercial considerations such as the cleaning of a product out of tanks

9.2.27. Certain products cannot be washed with water, due to reaction hazards 9.2.28. How the removal of residues by ventilation simplifies tank cleaning 9.2.29. The requirements for products which may be removed by ventilation 9.2.30.

- The resulting air pollution may be objected to by port authorities - Vapours rele ased may pose dangers to human health


Rev No: 0 Date: 20/07/2004 Page No: 30 of 33 9.2.31. The equipment required for ventilation 9.2.32. Ventilation procedures 9.2.33. With the aid of a flow diagram and a table of cleaning and disposal procedures (cdp),

determines the correct cleaning procedure for a tank equipped for efficient stripping and that has carried a nls, given:

9.2.34. - The name of the product - IBC code - The temperature - Whether the ship is inside/outside a special area

9.2.35. With the aid of a flow diagram and a table of slops disposal procedures (sdp), determines the correct procedure for disposal of nls slops, given: - The name of the constituent substances - IBCCODE - Their unloading temperatures - The ship is fitted or not fitted for efficient stripping - Whether the ship is inside/outside a special area

9.3. Gas-freeing of cargo tanks 9.3.1. The purpose of gas-freeing is to replace cargo vapours, inert gas or any other gas with

air 9.3.2. A responsible officer who is familiar with the vessel's system for gas-freeing should

supervise the gas-freeing operation 9.3.3. Equipment to be used for gas-freeing, such as:

- Fixed fans - Portable fans - Ejectors - Wind sails

9.3.4. Depending on the previous cargo and its cleanliness, a tank may be made gas-free by filling it completely with water and emptying it

9.3.5. Different ventilation methods with regard to the type of equipment, the weight of cargo vapours and the shape of a tank

9.3.6. General precautions when gas-freeing cargo tanks that contain flammable vapours 9.3.7. General precautions when gas-freeing cargo tanks that contain toxic gases 9.3.8. The effectiveness of a gas-freeing operation should be verified by regular checks of

the tank atmosphere 9.3.9. How checks, as referred to under objective 9.3.8, are carried out 9.3.10. With the aid of flammability diagram a gas-freeing operation by ventilation with air

of a tank: - Containing a mixture of cargo vapour and air - Containing a mixture of cargo vapour and inert gas

9.3.11. The atmosphere requirements for a cargo tank that is to be declared gas-free 9.4. Tests for cleanliness 9.4.1. Many cargoes in chemical tankers require a high degree of tank cleanliness for quality

reasons


Rev No: 0 Date: 20/07/2004 Page No: 31 of 33 9.4.2. A cargo tank is always inspected for cleanliness and general suitability prior to

loading 9.4.3. Inspections referred to under objective 9.4.2 may include chemical tests of the tank

surface 9.4.4. Tests of a cargo tank are carried out by independent surveyors who are accepted by

shippers, receivers and owners 9.4.5. A 'clean certificate' will be issued by the surveyor for a tank accepted for a cargo 9.4.6. Prior to a surveyor's inspection and tests, ship's officers should carry out tests for

cleanliness which can be carried out on board 9.4.7. Simple tests by ship's officers may ensure the best possible tank cleaning prior to

arrival in the loading port 9.4.8. Demonstrates a test for contamination by hydrocarbons 9.4.9. Demonstrates a test for contamination by chloride 10. Ship/shore interface 10.1. Liaison with terminals 10.1.1. Safe operation alongside a terminal is based on safety regulations, good

communication and a best possible co-operation between ship and terminal 10.1.2. Ship and terminal have a mutual duty to give the necessary information and to prepare

for berthing 10.1.3. The information to be made available by a terminal in the case of loading and/or

unloading 10.1.4. The information to be made available by a ship in the case of loading and/or

unloading 10.1.5. The responsibility for correct and safe operation in port is divided between the master,

the port captain and the terminal manager 10.1.6. The master should ensure proper liaison between the ship and the terminal 10.1.7. Prior to any loading or discharge operation, a pre-cargo-transfer meeting should be

held between the responsible personnel from the ship and the terminal 10.1.8. In general terms, the subjects to be discussed in a pre-cargo-transfer meeting 10.1.9. A ship/shore safety checklist should be completed jointly by the responsible personnel

on board and on the terminal 10.1.10. In reply to: general terms the checklist andthe reason for and the relevance of the

items on the list 10.1.11. Safety precautions and procedures for personnel on watch prior to and during

cargo-transfer operations 10.2. Shore reception facilities 10.2.1. Explain when shore reception facilities may have to be used other than to dispose of

prewash slops 10.2.2. Most ports require:

- Advance notification for disposal of nls wastes - Full and correct information on the nature of the nls - Disposal to appointed facilities only

10.2.3. From the port authorities' point of view, the reception of nls: - Could involve fire and incompatibility hazards



- Involves pollution hazards - Creates problems of disposal

10.2.4. Customs formalities may have to be completed when nls waste is disposed of 10.2.5. Possible problems that might be encountered with respect to the discharge to

reception facilities as: - No facilities being available - Insufficient capacity being available - Excessive disposal time, due to pumping restrictions, - Waiting time, need for shifting ship, stoppages, etc. - Unreasonably high cost

10.2.6. The above factors as resulting in inadequacy 10.2.7. The need for reporting inadequacies to the port authority and to flag state authorities 11. Emergencyoperations(3 hours) 11.1. Organizational structure and planning 11.1.1. The need for an emergency organization andthe main components of the organization

as: - An emergency command centre - An emergency party - A back-up emergency party - An engineer's group

11.1.2. The ship's muster list an emergency instructions should specify such details as: - The assembly point for personnel and the basic action for each group in the

emergency organization - The location of equipment for each group

11.1.3. All personnel should know their place in the emergency organization and be familiar with their duty in case an emergency procedure is initiated

11.1.4. Emergency operations have to be pre-planned and regularly exercised if they are to succeed

11.1.5. An emergency plan should be directed to: - Rescue and treatment of casualties - Safeguarding others - Minimizing the damage to the ship, to property and to the marine environment - Containing the incident and bringing it under control

11.2. Alarms 11.2.1. Fire alarm signals or general alarm signals are to be given in case of:

- Fire - Collision - Grounding - Man overboard - Major spillage of cargo liquid or release of vapour - Other emergency situations which call for emergency actions

11.2.2. A ship's muster list and emergency instructions should specify details of the emergency alarm signals

11.2.3. Other important alarms as:



- Cargo gas alarm - Cargo system alarm - Co2 or halon alarm - Radio alarm - Engine-room alarm - Inert-gas alarm

11.3. Emergency procedures 11.3.1. The ship's muster list and emergency instructions should specify action to be taken by

all crew members and officers in case of an emergency 11.3.2. Emergency procedures for accidents involving cargo spillage are given in the cargo

data sheets 11.3.3. The practical exercises of what to do in an emergency should be frequently carried out 11.3.4. The general procedure in an emergency should be:

- Alarm - Assembly - Crew check - Procedure for action

11.3.5. As a member of a group simulating an emergency organization on board, plans emergency procedures in case of: - Fire - Collision - Grounding - Cargo leakage - Bursting of a cargo hose or pipe - An accident in a cargo area, involving personnel

MASSA M A R I T I M E A C A D E M Y DIAGRAMS


Approximate Volume of the major cargo groups carried



Routes from crude oil natural gas to chemicals



States of aggregation illustrated in a temperature – pressure diagram

M A S S A MA R I T I M E AC A D E M Y DIAGRAMS




Molecular structures of some common chemical cargoes



Saturated hydrocarbons as gases, liquids and solids



Three ways of representing the molecular structure of benzene (C6H6)

Arenes (aromatic hydrocarbons)

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Position of tanks in a type 1 ship



A pressure / vacuum valve consisting of a combined high-velocity valve and a vacuum valve



Pump Types



Stripping arrangement for a deep well pump system (1)



Stripping arrangement for a deep well pump system (2)



Stripping arrangement for cargo systems with a separate pump-room



Types of gauging devices



The fire Triangle

MASSA MA R I T I M E A C A D E M Y CHEMISTRY


Atomic Theory An atom is electrically neutral, empty object who’s mass is concentrated at its centre. John Dalton regarded an atom as a hard dense and smallest indivisible particle of matter. Daltons Atomic Theory: The main points of this theory are:

1. Matter is made up of small individual particles known as atoms 2. An atom of a particular element all alike e.g. atoms of carbon are all similar in

nature. 3. Atoms of different elements are different in nature e.g. elements of c and o are

different in nature. 4. Atoms of elements have fixed mass e.g. c has 12 and o has 16 atomic mass unit 5. Atoms combines to form molecules e.g. 2 atoms of oxygen gives o2 molecule 6. Atoms are indestructible. It is not subdivided

Failure of Dalton’s theory

1. It fails to explain how the atoms of different elements differ from each other 2. It fails to explain the nature of forces that bind the atoms in a molecule 3. An atom of an element may not have fixed mass e.g. c has two different masses c-

12, c-14 and these are called Isotopes 4. Atoms is no longer considered to be indivisible it is divided into 3 fundamental

particles Electrons or cathode rays; Protons or Anode Rays; Neutrons. Structure of an atom



Discovery of Electrons The existence of electrons in atoms was first shown by J J Thomson by his discharge Tube Expt When high voltage is applied between the electrodes of the discharge tube, only at a very low pressure. A discharge took place between the electrodes during which a stream of cathode rays was emitted from the cathode. A fluorescence was seen on the wall opposite to the cathode .They were found to be made up of negatively charged particles called as electrons. Thomson showed that the nature of these particles are independent

1. of the nature of the material the cathode 2. the nature the gas in the discharge tube

Discovery of Protons or Anode Rays

A special type of cathode ray tube produces canal rays. The cathode is perforated and the tube contains gas at a very low pressure. When high voltage is applied to the tube cathode rays can be observed between the electrodes as in any cathode ray tube. On the other side of the perforated cathode, a different kind of ray is observed. These rays are attracted towards the negative plate brought along side the rays. The rays therefore mus t be composed of +vely charged particles. The production of canal rays is caused by the high energy electrons moving from the negative cathode to positive anode , hitting the molecules of gas occupying the tube Electrons are knocked from some atoms by the high energy electrons leaving each molecule with a +ve charge . The positively charged molecules are then attracted towards the negative electrode. Since the electrode is perforated, some of the positive particles go through the holes or channels, hence the name canal rays Discovery of Neutrons

In case of a number of elements, it was observed that the mass of the atom was twice the mass of protons in the atom. To account for this Rutherford predicted the presence of another particle, which would be electrically neutral and possess almost the same mass as that of the proton. Such a particle was later discovered by Chadwick and was named as neutron. Rutherford Scattering Expt



Rutherford bombarded a thin gold foil of thickness 0.00004 cm by alpha particles. The particles that emerged through the foil were allowed to fall on the Zns Screen. On collision they produce scintillations and hence could be detected .He observed that When alpha particles passes near the nucleus, the positive charge of the nucleus repels the +ve charge of the alpha particle, the path of the smaller particle is deflected . The closer the particle comes to the nucleus the more it is deflected. Those particles that meet the nucleus are bounced back towards the source by strong +ve +ve repulsion, since the alpha particle does not have enough energy to penetrate the nucleus

1. Most of the rays went straight through the foil

2. Some of the rays were deviated by small angles

3. Only few ray were deviated by large angles

4. Only one ray out of 20,000was rebounded back From these observations he concluded that

1. There is a lot of hollow space inside the atoms since most of the rays went undeviated

2. Inside the atom there must be a centre for + ve charge which repels the + ve charge due to which there are small deviations

3. alpha particles which make collisions with the +ve centre are deviated by large angles but such deviations are very few .the +ve charge centre must be very small in size

4. Inside the atoms there must be region where whole mass of the atom is concentrated. So when the rays collide in this region they get rebounded back. This region is termed as the Nucleus

5. The Nucleus is the centre of the +ve charge, which is very small in size where the whole mass of atom is concentrated , it comprises of N,P ,and E, which revolve close to the nucleus

Bohr Structure of Atoms The main points here are:

1. An atom is made up of three partic les: electrons, Protons and Neutrons.Electrons have negative charge, protons have positive charge and Neutrons have no charge, they are neutral. Due to presence of equal number of negative electrons and positive protons, the atom on the whole is electrically neutral.

2. The protons and neutrons are located in a small nucleus at the centre of the atom. Due to presence of protons, nucleus is positively charged.

3. Electrons revolve around the nucleus in a fixed circular paths called energy levels or shells. The energy levels are represented in two ways either by the numbers 1,2,3,4 or by letters K, L, M, N. the energy levels are counted centre outwards

4. Each energy level is associated with a fixed amount of energy, the shell nearest to the nucleus having minimum energy and the shell farthest from the nucleus having the maximum energy.



5. There is no change in the energy of the electrons as long they keep revolving in the same energy level, and the atom remains stable. The change in energy of an electron takes place only when it jumps from a lower energy level to a higher energy level or when it comes down from a higher energy level to a lower energy level. When an electron gains energy it jumps from a lower energy level to higher energy level. When a electron comes down from a higher energy level to a lower energy level it loses energy. The amount of energy absorbed or emitted is not continuous but it is discontinuous in the form of small packets of energy known as Photons or Quanta (E) Energy associated with each photon os hv

6. The amount of energy (E) associated with each quanta of radiation is directly proportional to its frequency(v)

E hv where h is Planck constant h= 6.626 10 27

Atomic Number: (Z) Atomic number is the number of protons present in the nucleus of an atom. As an atom is electrically neutral the number of protons is equal to the number of electrons. Thus no of protons = no of electrons=atomic number e.g 6C i.e 6 electrons are present in the carbon atom

Mass Number (A) The number of nucleons i.e the total of protons and neutrons in the nucleus of an atom is called the mass number Thus A= Z=N where N- no of neutrons e.g there are 11protons and 12 neutrons in the nucleus of Na atom its mass no is (11+ 12) = 23

Isotopes: Isotopes are different atoms of the same element having same atomic number (same no of protons) but different mass numbers (different no of neutrons)

Isotopes of an element have different mass numbers because they contain different number of neutrons

e.g. chlorine has 17 protons so atomic number is 17,some Cl atoms have 18 neutrons whereas other Cl atoms have 20 neutrons . Therefore chlorine can have mass number 17+ 18 = 35 or 17+ 20 = 37thus chlorine has two isotopes of mass numbers 35 and 37 respectively the two isotopes can be written as Isotopes of Carbon The carbon atom has common isotopes having the same atomic number of 6 but different mass numbers of 12 and 14 The two isotopes are represented as follows Isotopes show the same chemical properties but different physical properties



The chemical properties of an atom depend on the number of valence electrons in it .In other words the chemical properties depend upon its electronic configuration. Since all isotopes of an element have identical electronic configurations, therefore all isotopes of an element show identical chemical properties. Isotopes of Hydrogen The hydrogen element has atomic number 1 and mass numbers 1,2,3 and can be represented as

Quantum Numbers : The numbers which assign the position and energy to an electron in the atom are called quantum numbers It was that four quantum numbers are necessary to describe the electron completely The four Quantum Numbers are



1. Principal Quantum Numbers (n) It decides the probable position and energy of the electron in the atom. It is allowed to take integral values such as 1, 2, 3------excluding zero. Its value describes the orbit or the shell in which the electron revolves around the nucleus. When n=1 it is K shell When n=2 it is L shell When n=3 it is M shell When n=4 it is N shell 2. Azimuthal or Secondary Quantum Number (l)

l determines to some extent the energy of the electron and gives the sub shell or sublevel to which the electron belongs. The subshells differ slightly in energy. The allowed values of l depend on the value of n and for a given n its allowed values are 0, 1, 2, 3, --------- (n-1) When l=0 the corresponding subshells is‘s’ When l=1 the corresponding subshells is ‘p When l=2 the corresponding subshells is‘d’ When l=3 the corresponding sub shell is ‘f respectively

Magnetic Number: The angular momentum of an electron gives rise to magnetic field which interacts with externally applied magnetic field.The magnetic quantum number determines the number of preferred orientations of electrons in space. The allowed values of m depend on that of l, and for given l, m takes integral values from + l to – l through O.

The Magnetic Quantum number determines the total number of orbitals that make up a given subshe lls. Thus, p sub shell consists of three orbitals while d subshells consists of five orbitals

Spin Quantum Number: The electron spins around its own axis while revolving around the nucleus. This gives rise to spin quantum number. Two directions of spin are possible for the electron namely clockwise and anti clockwise. Corresponding to these directions the spin quantum number is designated as + ½, and – ½ or by arrows pointing in opposite directions.

Periodicity of Elements The process of arranging similar elements in one group and separating them from other dissimilar elements is called classification of elements. A table which has been framed with the help of classification of elements is called the periodic table. Periodic table is the tabular arrangement of all known elements based on periodic law. The periodic table is useful to study the properties of elements and their compounds in a simple and easy way . The original form of periodic table was put forward by Mendeelev in 1869.The modern form of periodic table is the long form of periodic table. Mendeelev Periodic Law



Mendeelev formulated his perdic law called Mendeelev Perodic Law which states that “The Physical and chemical properties of the elements are periodic functions of their atomic weight i.e when elements are arranged in the increasing order of their atomic weight; similar elements recur after regular intervals i.e. periodically.

1. On the basis of his periodic law Mendeelev constructed a Perodic table of elements in which the elements are arranged in horizontal rows called periods in order of their atomic weights and in vertical columns called groups according to resemblance in their properties

2. There were seven periods (horizontal rows) and eight groups (vertical columns) in the periodic table. Out of the eighth groups , seven groups are normal elements and 8th group is of transition elements

3. It includes all the elements known up to present time. Zero Group is the noble gases which were unknown in Mendeelev time

4. There is a diagonal relationship between the elements, that is diagonally opposite elements of different periods show considerable resemblance in their properties

5. Mendeelev table has been modified after the replacement of the atomic weight by atomic number

Drawbacks of the old periodic law

1. Position of hydrogen Hydrogen element has been placed at the top of the group 1 , above the alkali metals because the electronic configuration of hydrogen is similar to those of alkali metals , both hydrogen as well alkali metals have 1 valence electron each Since hydrogen atom is very small in size many properties of hydrogen are different from those of alkali metals . Therefore while discussing the alkali metals of group 1 , hydrogen is never included. Hydrogen is treated as a very special element and placed alone at the head of the Perodic table

2. Position of Isotopes Isotopes are the atoms of the same element having similar chemical properties but different atomic masses.( same atomic number but different mass number)If they are arranged according to their atomic masses , the isotopes should be placed in different groups in the periodic table . The isotopes were not given separate places in Mendeleef’s periodic table

3. Anomalous behaviour of elements : According to Mendeleef’s periodic law the elements are arranged in the order of their increasing atomic masses, so the elements with the lower atomic masses should come should come first, and the element with higher atomic, masses should come later. When certain elements were put in their correct group on basis of their chemical properties, it was found that elements with higher atomic mass comes first and element with lower atomic mass comes later for e.g argon is an inert gas and is to be grouped with inert gas whereas potassium is an alkali metal which should be grouped with alkali metal, in doing so argon with atomic mass 40 comes first and potassium with atomic mass 39 comes later. 4. There was no place for rare earth elements in the periodic table

Classification of elements on the basis of electronic configuration



Inert Gas: These are the elements in the atoms of which the outermost shell is complete. There are six gases He, Ne, Ar, Kr, Rn. Valency Shell configuration for these gases is ns2 np6. Because of the stable configuration these elements show very little tendency to form chemical compounds with other elements. Normal or Representative Elements These are the elements in the atoms of which the outer most shell i.e the nth shell is only incompletely filled to capacity. The electronic configuration in the outermost shell of the atoms of these elements varies from ns1 to ns2 ,np5. They include metals, non metals and metalloids Transition Elements: These are the elements in the atom of which the two outermost shells are incompletely filled and Valency electrons are available from them Inner transition Elements : These are the elements in the atoms of which three outermost shells are incompletely filled. Periodic Table



Long Form of periodic table The modern periodic table was prepared by Bohr. It is also known s long form of periodic table The table consists of 105 elements arranged in increasing order of their atomic number. In the table there are 7 horizontal rows called Periods and 18 vertical columns corresponding to 16 groups The periods are numbered as 1,2,3,4 while the groups are numbered as IA, IIA, IIIA----VII A However the group VIII in the centre contain three vertical columns Table is divided into three main portions Left , Right and middle Left Portion:

1. Consists of elements of groups IA &II A 2. They are highly reactive metals

Middle Portion:

1. Consists of groups IIIB, IVB. VB,VIB,VIIB,VIII, IB, & IIA 2. They include transition elements and inner transition elements



Right portion 1. This portion consists of elements of group IIIA to VII A along with Zero group 2. It includes poor metals such as tin, bismuth lead , metalloids and non metals

General characteristics of periods and groups

1. The seven horizontal rows in the periodic table constitute seven periods of elements

2. The first , second and third period contain 2,8,8 elements respectively and are called Short Periods

3. The fourth , Fifth and sixth period contain 18,18 and 32 elements respectively and are called Long Periods

4. The seventh period is incomplete period of 19 elements. When completed it will contain 32 elements

5. Every period begins with an alkali metal and ends with an inert gas 6. In each period there is a gradual variation in the properties of the elements with

increasing atomic numbers. e.g. in moving across any period from left to right , the size of the atom decreases , the metallic character of the element decreases and their oxides become more and more acidic

7. In case of long periods the variation in the properties become much more smooth after every period there is a recurrence of elements having similar properties.

8. Elements belonging to each group have similar properties The variation is merely in degree and not in the nature of the property for e.g all group IA elements are alkali metals (soft metals)have low M.P



Chemical Bond

Most of the elements do not exist individually as free atoms in the nature, except noble gases , atoms of all other elements have a tendency to combine with each other or with other atoms to form clusters or aggregates of atoms with definite composition . A cluster of atoms which is electrically neutral and in which the atoms are held together is called a molecule. The force which holds the atoms together in a molecule is known as Chemical Bond. Thus a chemical bond is defined as the force that holds two or more atoms together in a molecule or ion. Electronic theory of Valency According to Kossel and Lewis, the nature of a chemical bond is determined by the arrangement of electrons in the outermost she ll of the atoms. Only those electrons present the outermost shell of an atom participate in the formation of a chemical bond . The nature of a chemical bond could be explained on the basis of the octet rule. Octet Rule This rule states that, in the formation of a chemical bond, atoms of the elements gain, lose or share electrons, such that the outermost (valence) shell of the atoms contain eight electrons, as in the nearest or neighbouring inert gases. Thus the atoms involved in the bond formation acquire more stability and minimum energy. On basis of the octet theory the formation of the following chemical bonds can be explained. Ionic Bond (Electrovalent Bond) An ionic bond is defined as the interionic electrostatic force of attraction between oppositely charged ions (cations and anions) In this type of bond transfer of electrons take place from the valence shell of one atom to the valence shell of another atom. Atoms which lose electron acquire a positive charge and are called as cations and the atom which gains electrons acquires negative charge known as anions Example formation of NaCl molecule Sodium metal reacts with chlorine to form an electrovalent compound, sodium chloride The atomic number of sodium 11, so its electronic configuration is 2,8,1. Sodium atom has only one electron in its outermost shell. So the sodium atom donates 1 electron and forms a sodium ion Na+ Na atom----------------- Na+ 2,8,1 2,8



Sodium ion Na+ formed here has an electron arrangement similar to the inert gas neon, so it is very stable Let us now consider chlorine, Cl has atomic number 17, so its electronic configuration is 2, 8, 7. Chlorine atom has 7 electrons in its outermost shell and needs one more electron to achieve the stable 8-electron inert gas configuration. So chlorine atom takes 1 electron from sodium and forms a negatively charged chloride ion Cl –

Cl ---------------------- Cl

Chlorine atom chloride ion 2,8,7 2,8,8 Chloride ion formed here has an electron arrangement similar to the electron arrangement of inert gas argon, so it is very stable Sodium ions have +ve charge whereas chloride ions have –ve charge. Due to opposite charges, sodium ions and chloride ions are held together by electrostatic force of attraction to form sodium chloride. Covalent Bond The chemical Bond formed by sharing of electrons between two atoms is known a covalent bond. The sharing takes place in such a way that each atom in resulting molecule gets the stable electron arrangement of an inert gas Single covalent Bond A covalent bond may be defined as a bond which is formed by sharing of one or more pairs of electrons between the atoms in a molecule or an ion Formation of chlorine molecule E.g. electronic configuration of chlorine molecule is 1s2 2s2 2p63s2 3p5

A chlorine atom is very reactive and cannot exist free because it does not have the stable electron arrangement of an inert gas. Chlorine gas, therefore does not consist of single atoms, it consists of more stable Cl2 molecules. Each molecule of chlorine contains two chlorine atoms joined by a single covalent bond The atomic number of chlorine is 176 so its electronic configuration is 2,8,7. Chlorine atom has 7 electrons in its outer most shell and needs one more electron to complete its octet and become stable. It gets this electron by sharing with another chlorine atom. So two chlorine atoms share one electrons form a chlorine molecule Because the two chlorine atoms share electrons, there is a strong force of attraction between them which holds them together. This force is called a covalent bond. The bonded chlorine atoms thus forms a chlorine molecule. Since two chlorine atoms share one pair of electrons the bond between them is called a single covalent bond or just a single bond. In fact each chlorine atom in the chlorine molecule has electronic configuration of 2, 8, and 8 resembling its nearest inert gas argon Double covalent bond It is formed when two electron pair are shared between the two atoms



Formation of oxygen molecule Oxygen atom is very reactive and cannot exist free because it does not have the stable , inert gas electron arrangement its valence shell. Oxygen gas therefore does not consist of single atoms O it consists of more stable O2 molecules. The formation of an oxygen from two atoms of oxygen can be explained on the basis of electronic theory of Valency The atomic number of oxygen is 8, so its electronic is 2, 6. Thus an oxygen atom has 6 electrons in its outermost shell. Since it has 6 electrons it requires 2 more electrons to achieve the stable 8 electron inert gas configuration. The oxygen atom gets these electrons by sharing its two electrons with the two electrons of another oxygen atom. So the two oxygen atoms share two electrons each and form a stable oxygen molecule Since the oxygen atoms share two pairs of electrons , the bond between them is called a double covalent bond or just a double bond thus in a oxygen molecule the two oxygen atoms are held together by a double covalent bond and a double bond is stronger than a single bond Triple Covalent Bond It is formed when three pair of electrons are shared between the two atoms A nitrogen atom is very reactive and cannot exist freebecause it does not have the stable electron arrangement of an inert gas . Nitrogen gas therefore does not consist of single atoms , it consists of more stable nitrogen molecules Coordinate Bond It is formed by sharing as well as partial transfer of electrons between the two atoms Here the electrons are donated by one atom and the other atom is the acceptor e .g. in the formation of NH4 ion , NH3 nitrogen shares three electrons with Hydrogen and one pair of electrons is transferred to H ion to form NH4 NH3 gets a partial positive charge and H gets a partial negative charge

ORGANIC CHEMISTRY INTRODUCTION

♦ Organic Chemistry is the chemistry of specific carbon compounds.

♦ Organic compounds are derived from living sources like animals and plants though today most of them are synthesized.

♦ The scope of organic chemistry is very large and the number of carbon

compounds far exceeds the number of compounds of all remaining elements put together.



♦ . From the basic requirements of lif e like food [vegetables, cereals, fats, sugars etc.

♦ Clothing [cotton, silk, wool etc.] and ♦ Medicines [sulpha drugs, antibiotics etc.] to ♦ Industries [dyes, paints, plastics, rubber, petroleum, etc. all seem to have an

organic origin. CHARACTERISTICS OF ORGANIC COMPOUNDS.

1. Composition

Built up mainly of carbon and hydrogen. In addition in some compounds the following elements-oxygen, nitrogen, sulphur phosphorus and halogens may also be present.

2. Nature

They are non-ionic and contain covalently bonded carbon atoms. Carbon has the unique property of combining with any number of carbon atoms and also with other elements forming almost an unlimited number of compounds. This unique property of carbon atoms is called 'catenation'

3. Solubility: General insoluble in water but soluble in organic solvent

4. Melting & boiling point: Generally have relatively low melting and-boiling points 5. Combustibility: On burning in oxygen produce carbon dioxide and water.

6. ISOMERISM. Certain organic compounds exhibit isomerism. Isomers are organic

compounds having same molecular formula but-different structural formula. E.g. Butane [C4HIO] forms two isomers, n-butane [straight chain] and iso-butane [branched chain structure].



Hydrocarbons

Organic compounds: are of two types Aliphatic and Aromatic Aliphatic are again divided into ---- Saturated and -Unsaturated Saturated ---- Alkanes Unsaturated --- Alkenes and Alkynes Saturated hydrocarbons Source – Natural gas Contains 75% of methane along with other hydrocarbons Petroleum Marsh gas --- bacterial decay of vegetable matter They are also called as paraffin (little affinity) General formula CnH2n+2 e.G Methane CH4 AAllkkaanneess aanndd tthheeiirr mmoolleeccuullaarr ffoorrmmuullaa Methane CH4 Ethane C2H6 Propane C3H8 Butane C4H10 PentaneC5H12

Hexane C6H14 Heptane C7H16

Octane C8H18 Nonane C9H20

Decane C10 H22 PPrrooppeerrttiieess C1 – C4 are colourless Gases Methane , ethane, propane, and butane are colorless gases at ordinary temperature



C5-C17 are colorless liquids Greater than C17 colorless are solids The first four alkanes are odourless C5-C15 have benzene odour The higher are odourless Insoluble in water but soluble in organic solvent AAllkkeenneess alkene is a hydrocarbon that has a double bond between two carbon atoms. Alkenes are unsaturated substances Also called as olefins . (Oil Forming) General formula Cn H2n Source: Cracking of petroleum Cracking involves breaking down of larger molecules into smaller molecules, i.e rupture of C-C rupture of C-C and C-H bond PPrrooppeerrttiieess Lower alkenes are colourless gases Higher alkenes are colourless liquids or solids Alkenes are odourless except ethylene which has a sweet odour Are insoluble in water, but soluble in organic solvents AAllkkeenneess ccaarrrriieedd iinn GGaass ccaarrrriieerrss Ethylene C 2 H 4 Propylene C 3 H 6 Butylenes C 4 H 8



AAllkkyynneess Are also called as Acetylenes Aliphatic unsaturated compounds They contain carbon carbon triple bond General formula Cn H2n-2 Source: Prepared from Natural Gas and from higher alkanes obtained from petroleum Ethyne C2 H2

MASSA M A R I T I M E A C A D E M Y DEFINITIONS


For the purposes of this Guide the following interpretations apply: Acute Toxic Effect The effect on humans of a single exposure of short duration to high

concentrations of a toxic compound or toxic vapour (see also Chronic Toxic Effect).

Alcohol Resistant Foam (Alcohol-type Foam) : A multi-purpose fire fighting foam effective against many water soluble cargoes. It is also effective against many non-water soluble cargoes. This is the most commonly used type of fire fighting foam on chemical tankers.

Anae sthesia: A total loss of feeling and consciousness, or the loss of power or feeling over a

limited area of skin.

Anaesthetics: Chemicals which produce anaesthesia. Approved Equipment: Equipment of a design that has been tested, approved and certified by

an appropriate authority, such as an administration or classification society, as safe for use in a specified hazardous atmosphere.

Aqueous: Indicating that the compound is in solution in water.

Asphyxia: The condition arising when the blood is deprived of an adequate supply of oxygen,

so that loss of consciousness may follow. Asphyxiant: A gas or vapour, which may or may not have toxic properties, which when

present in sufficient concentrations excludes oxygen and leads to asphyxia.

Auto-ignition Temperature (Autogenous Ignition Temperature; Ignition Temperature): The lowest temperature to which a solid, liquid or gas requires to be raised to cause self-sustaining combustion without initiation by a spark or flame or other source of ignition (see also Flash Point).

BCH Code: The IMO Code for the Construction and Equipment of Ships Carrying Dangerous

Chemicals in Bulk. Boiling Point: The temperature at which the vapour pressure of a liquid equals that of the

atmosphere above its surface; this temperature varies with pressure. Boiling Range: Some liquids which are mixtures, or which contain impurities, boil over a

range of temperatures known as the boiling range. When this occurs, the range will be stated on the data sheet. The low temperature is that at which components within the liquid start to boil.

Bonding (electrical) The connecting together of metal parts to ensure electrical continuity.



Bulk: The term 'in bulk' refers to carriage of cargo in tanks or pressure vessels which are

constructed as part of the ship, the contents being loaded and discharged by the ship's installed handling system.

Cargo Area That part of the ship, which contains the whole cargo system and cargo

pumprooms, and includes the full beam deck area over the length of the ship above the cargo containment system. Where fitted, the cofferdams, ballast or void spaces at the after end of the aftermost cargo space or at the forward end of the forward cargo space are excluded from the cargo area.

, Cargo Handling(Cargo Operations): The loading, storing, discharging, circulating and

transferring of bulk liquid cargo, and associated tank cleaning and gas freeing. Cargo Information Form : See Data Sheet. Catalyst: A substance that starts or changes the rate of a reaction without being itself

chemically changed. A catalyst which reduces the rate of a reaction is known as a negative catalyst.

Certificate of Fitness A certificate issued by the flag administration confirming that the

structure, equipment, fittings, arrangements and materials used in the construction of a chemical tanker are in compliance with the relevant IMO Chemical Codes. Such certification may be issued on behalf of the administration by approved classification societies.

Certified Gas Free: Certified gas free means that a tank, compartment or container has been

tested by an authorised person using an approved testing instrument, and found to be in a suitable condition -i.e. not deficient in oxygen and sufficiently free from toxic or flammable gases -for a specified activity such as hot work, and that a certificate to this effect has been issued.

Chemical Absorption Detector (Gas Absorption Detector): An instrument used for the

detection of vapours, which works on the principle of a reaction between a vapour and the chemical agent in the apparatus; either the vapour discolours the agent or the agent dissolves some of the vapour .

Chronic Toxic Effect The cumulative effect on humans of prolonged exposures to low

concentrations of a toxic compound or toxic vapour, or of intermittent exposures to higher concentrations (see also Acute Toxic Effect).

Closed Gauging System(Closed Ullaging): A system where by the contents of a tank can be

measured by means of a device which penetrates the tank, but which is part of a closed system and prevents tank contents from being released. It can be mechanical, electronic, and magnetic or pressure operated (see also Open Gauging System and Restricted Gauging System).

Combustible (Flammable): Capable of being ignited and of burning. For the purposes of this

Guide the terms combustible and flammable are synonymous.



Combustible Gas Indicator (Explosimeter):

An instrument for detecting a combustible gas/air mixture, usually measuring its concentration in terms of the Lower Flammable Limit (LFL).

Corrosive Liquids:

Liquids which can corrode normal constructional materials at an excessive rate. Usually they also cause serious damage to human tissue and eyes.

Data Sheet (Cargo Information Form):

A document, in accordance with the IMO Codes and usually from the manufacturer of the cargo that contains necessary information about the properties of the chemical for its safe carriage as cargo.

Density Mass per unit volume, measured in a vacuum (see also Litre Weight). Endothermic : A process which is accompanied by absorption of heat. Exothermic :A process which is accompanied by evolution of heat. Explosimeter : See Combustible Gas Indicator. Explosion Proof Equipment/ Flame Proof Equipment:

Equipment or apparatus which will withstand, without damage and in accordance with its prescribed rating, any explosion of a prescribed flammable gas to which it may be subjected under practical operating conditions, and which will prevent the transmission of flame to the surrounding atmosphere

Explosive Limits See Flammable Limits. Explosive Range See Flammable Range. Filling Ratio (for Liquids) That volume of a tank, expressed as a percentage of the total

volume, which can be safely filled by liquid when allowing for the possible expansion of the liquid.

Flame Arrester A device used to arrest the passage of flame in a pipeline. Flame Proof Equipment: See Explosion Proof Equipment. Flame Screen (Gauze Screen): A portable or fitted device incorporating one or more

corrosion resistant wire woven fabrics of very small mesh used for preventing sparks from entering a tank or vent opening. For a short period of time a flame screen will prevent the passage of flame, yet permit the passage of gas.



Flammable (Combustible): Capable of being ignited and of burning. For the purposes of this Guide the terms combustible and flammable are synonymous.

Flammable Limits (Explosive Limits): The minimum and maximum concentrations of vapour

in air which form flammable (explosive) mixtures are known as the lower flammable limit (LFL) and upper flammable limit (UFL) respectively. These terms are synonymous with lower explosive limit (LEL) and upper explosive limit (UEL) respectively.

Flammable Range (Explosive Range): The range of flammable vapour concentrations in air

between the lower and upper flammable limits. Mixtures within this range are capable of being ignited and of burning.

Flash Point The lowest temperature at which a liquid gives off sufficient vapour to be ignited.

This temperature is determined by laboratory testing in a prescribed apparatus (see also Auto-ignition Temperature).

Foam A froth creating an air-excluding blanket, and used for fire fighting. Freezing Point (Melting Point): The temperature at which the liquid state of a substance is in

equilibrium with the solid state, i.e. at a higher temperature the solid will melt and at a lower temperature the liquid will solidify. Freezing point and melting point may not always coincide, but they are sufficiently close to enable the difference, between the m to be ignored for the purposes of this Guide.

Gas: This term is used to cover all vapour mixtures or vapour-and-air mixtures. Gas Absorption Detector: See Chemical Absorption Detector. Gas Free Gas free means that a tank, compartment or container has been tested using

appropriate gas detection equipment and found to be not deficient in oxygen and sufficiently free, at the time of the test, from toxic, flammable or inert gases for a specified purpose.

Gauging: See Closed Gauging System, Open Gauging System and Restricted Gauging

System. Gauze Screen: See Flame Screen. Hazardous Area: An area in which vapour may be present continuously or intermittently in

sufficient concentrations to create a flammable atmosphere or an atmosphere, which is dangerous for personnel.

Health Hazard: A general descriptive term for a danger to the health of personnel. Hot Work: Work involving flames, incendive sparks or temperatures likely to be sufficiently

high to cause ignition of flammable gas. The term includes any work involving the use of welding, burning or soldering equipment, blow torches, some power driven tools, portable



electrical equipment which is not intrinsically safe or contained in an explosion proof housing, and equipment with internal combustion engines.

Hot Work Permit A document issued by an authorised person permitting specified work to be

done for a specified time in a defined area, employing tools and equipment which could cause ignition of flammable gas (see Hot Work).

IBC Code: The IMO International Code for the Construction and Equipment of Ships

Carrying Dangerous Chemicals in Bulk. Ignition Temperature : See Auto-ignition Temperature. IMO: The International Maritime Organization; a specialised agency of the United Nations. IMO Codes: See BCH Code and IBC Code. The Codes are described in Chapter 4. Incendive Spark: A spark of sufficient temperature and energy to ignite a flammable

atmosphere. Inert Gas: A gas or vapour containing insufficient oxygen to support combustion. Inerting: The introduction of inert gas into a space to reduce and maintain the oxygen content

to a level at which combustion cannot be supported, or to maintain the quality of the cargo. . Ingestion: The act of introducing a substance into the body via the digestive system. Inhibited Cargo: A chemical cargo to which an inhibitor has been added. Inhibitor: A substance used to prevent or retard cargo deterioration or a potentially hazardous

chemical self-reaction, e.g. polymerisation. Insulating Flange An insulating device placed between metallic flanges, bolts and washers, to

prevent electrical continuity between pipelines, sections of pipelines, hose strings and loading arms, or equipment or apparatus. -

Intrinsically Safe : Intrinsically safe equipment, instruments or wiring are incapable of

releasing sufficient electrical or thermal energy under normal or abnormal conditions to cause ignition of a specified hazardous atmospheric mixture in its most easily ignited concentration.

Irritating Liquid: A liquid, which on direct contact with the eyes or skin will cause severe

irritation, injury or burns. Irritating Vapour A vapour which will cause irritation of the eyes, nose, throat and

respiratory tract. ISGOTT: The International Safety Guide for Oil Tankers and Terminals.



LFL or LEL: See Flammable Limits. Litre Weight Mass per unit volume, measured in air (see also Density). Loading Overall (Over the Top): Loading through hatches or other deck openings by

means of portable open-ended pipes or hoses. Manifold Valves: Valves in a tanker's piping system immediately adjacent to the

ship/shore connecting flanges. MARPOL: The International Convention for the Prevention of Pollution from Ships 1973,

as modified by its Protocol of 1978.

Melting Point: See Freezing Point.

MFAG: The IMO Medical First Aid Guide for Use in Accidents Involving Dangerous Goods.

Miscibility: The ability of a liquid or gas to dissolve uniformly in another liquid or gas.

Gases mix in all proportions but the miscibility of liquids depends upon their chemical properties. Similar chemicals mix in all proportions (e.g. alcohol and water) but others are only partly miscible (e.g. benzene and water). Many gases are miscible with liquids.

MSDS or Material Safety Data Sheet: See Data Sheet.

Mucous Membranes: Those surfaces of the human respiratory system lined with

secretion; for example, the inside of the nose, throat, windpipe and lungs. Can also be applied to the eyes.

Naked Lights: Open flames or fires, exposed incandescent material or any other

unconfined source of ignition.

Narcosis: A condition of profound insensibility, resembling sleep, in which the unconscious person can only be roused with great difficulty but is not entirely indifferent to sensory stimuli.

Odour Threshold: The smallest concentration of gas or vapour, expressed in parts per

million (ppm) by volume in air, that most people can detect by smell.

Open Gauging System: A system of measuring the contents of a tank, which makes use of an opening in the tank and may expose the gauger to the cargo or its vapour (see also Closed Gauging System and Restricted Gauging System).

Over the Top: See Loading Overall.



Oxidising Agent: An element or compound that is capable of adding oxygen or removing hydrogen; or one that is capable of taking one or more electrons from an atom or group of atoms (the opposite of a Reducing Agent).

Oxygen Analyser An instrument used to measure oxygen concentrations, expressed as a

percentage by volume.

Padding: Filling and maintaining the cargo tank and associated piping system with an inert gas, other gas or vapour, or liquid, in order to separate the cargo from air.

Peroxides: Compounds formed by the chemical combination of cargo liquid or vapour

with atmospheric oxygen, or oxygen from another source. These compounds may in some cases be highly reactive or unstable and constitute a potential hazard.

PH: A scale which indicates the acidity or alkalinity of a solution. Its range is 0 to14. pH 7

represents absolute neutrality. A value of 0 represents high acidity (e.g. concentrated acids) and 14 represents high alkalinity (e.g. a caustic soda solution).

Poison: A very toxic substance which when absorbed into the human body by ingestion,

skin absorption, or inhalation produces a serious or fatal effect.

Polymerisation The phenomenon whereby the molecules of a particular compound link together into a larger unit containing anything from two to many thousands of molecules, the new unit being called a polymer. A compound may thereby change from a free flowing liquid into a viscous one or even a solid. A great deal of heat may be evolved when this occurs. Polymerisation may Occur spontaneously with no outside influence, or it may Occur if the compound is heated, or if a catalyst or impurity is added. Polymerisation may, under some circumstances, be dangerous but may be delayed or controlled by the addition of inhibitors.

Pour Point: The lowest temperature at which a liquid will remain fluid

Pressure Force per unit area. Usually expressed as gauge pressure relative to atmosphere

(as shown on a gauge that registers zero at atmospheric pressure) or absolute pressure.

Pressure Vacuum Valve (P/V Valve): A dual purpose valve commonly incorporated in the cargo tank venting system of tankers, the operation of which, when appropriately set, automatically prevents excessive pressure or vacuum in the tank or tanks concerned.

Putrefaction: The natural decomposition, over time, of animal or vegetable oils,

accompanied by offensive smells. Sometimes called 'going off'.

Reducing Agent: An element or compound that is capable of removing oxygen, or adding hydrogen; or one that is capable of giving one or more electrons to an atom or group of atoms (the opposite of an Oxidising Agent). -.



Reid Vapour Pressure (RVP): The vapour pressure of a liquid determined by laboratory testing in a standard manner in the Reid Apparatus at a standard temperature of 100°F (37.8°C) expressed in pounds per square inch absolute, and commonly written 'RVP lb'

Relative Vapour Density The relative weight of the vapour compared with the weight of

an equal volume of air at standard conditions of temperature and pressure. Thus vapour density of 2.9 means that the vapour is 2.9 times heavier than an equal volume of air, under the same physical conditions.

Respiratory Tract: The human air passages from nose to lungs inclusive.

Responsible Officer The master or any officer to whom the master has delegated

responsibility for an operation or duty.

Responsible Terminal (Representative): See Terminal Representative.

Restricted Gauging System A system employing a device which penetrates the tank and which, when in use, permits a small quantity of cargo vapour or liquid to be exposed to the atmosphere: when not in use, the device is completely closed (see also Closed Gauging System and Open Gauging System).

Safety Relief Valve: A valve fitted on a pressure vessel to relieve overpressure. Self-reaction: The tendency of a chemical to react with itself, usually resulting in

polymerisation or decomposition. Self-reaction may be promoted by contamination with small amounts of other materials.

Short Term Exposure Limit (STEL): See Threshold Limit Value. SOLAS The International Convention for the Safety of Life at Sea 1974, as modified by its

Protocol of 1988.

Solubility :The ability of one substance (solid, liquid or gas) to blend uniformly with another. Solubility is usually understood as the maximum weight of substance which will dissolve in water in the presence of undissolved substance. The value is usually expressed as the number of grams of substance dissolving in 100 grams of water. In the case of liquid dissolving in another liquid, the term miscibility is often used instead of solubility.

Specific Gravity The ratio of the weight of a volume of a substance at a given temperature

to the weight of an equal volume of fresh water at the same temperature or at a different given temperature. Since temperature affects volume, the temperature at which a specific gravity comparison is made needs to be known, and is stated after the ratio.

Spontaneous Combustion: Ignition of a combustible material is termed 'spontaneous' if

the inherent characteristics of the material cause a heat producing (exothermic) chemical action and thus ignition without exposure to external fire, spark or abnormal heat.



Static Electricity: The electrical charge produced on dissimilar materials through physical contact and separation, such as is caused by a fluid passing through a pipeline or into a tank.

Stern Discharge Line: A cargo pipe line over the deck to a point terminating at or near the

stern of the tanker.

Stripping: The final operation in pumping bulk liquid from a tank or pipeline. Sweeping (Squeegeeing or Puddling): The manual pushing of semi-liquid residues of

animal fat or vegetable oil cargoes towards the pump suction during the final stages of discharge, using sweeping sticks or squeegees.

Systemic Toxic Effect The effect of a substance or its vapour on those parts of the human

body with which it is not in contact. This presupposes that absorption has taken place. It is possible for chemicals to be absorbed through skin, lungs or stomach, producing later manifestations which are not a result of the original direct contact.

Tank Vent System (Vent Line): The piping system and associated valves, installed to

prevent overpressure or under pressure (vacuum) in cargo tanks.

Terminal Representative A person designated by the terminal to take responsibility for an operation or duty.

Threshold Limit Value (TLV) (Short Term Exposure Limit): The time weighted

average (TWA) concentration of a substance to which it is believed workers may be repeatedly exposed, for a normal 8 hour working day and 40 hour working week, day after day, without adverse effect. It may be supplemented by other limits.

Topping Off: The operation of completing the loading of a tank to a required ullage. Toxic: Poisonous, i.e. causing bodily harm that may be severe (see also Acute Toxic Effect

and Chronic Toxic Effect).

Toxic Liquid A liquid which if ingeste d or absorbed through the skin causes bodily harm that may be severe.

Toxic Vapour: A vapour, which if inhaled causes bodily harm that may be severe.

UFL or UEL: See Flammable Limits. Ullage: The depth of free space left in a cargo tank above the liquid level. Vapour: One or more of the components of chemical products when in the vapour phase.

Vapour Pressure : The pressure exerted by the vapour above the liquid, at a given

temperature. It is expressed as absolute pressure.



Venting: The release of cargo vapour or inert gas from cargo tanks and associated systems.

Vent Line: See Tank Vent System. I Viscosity: The property of a liquid, which determines its resistance to flow. Volatile Liquid: A liquid, which evaporates readily at ambient temperatures. Volatility: The tendency for a liquid to vaporise. Water Fog Very fine droplets of water generally delivered at a high pressure through a fog

nozzle.

Water Spray: Water divided into coarse drops by delivery through a special nozzle. Water Spray System A system of sufficient capacity to provide a blanket of water

droplets to cover the cargo manifolds, deck storage tanks, and boundaries of superstructures and deckhouses.

MASSA M A R I T I M E A C A D E M Y GLOSSARY OF ABBREVIATIONS


ACGIH: American Council of Governmental Industrial Hygienists BCH: Code for the Construction and Equipment of Ships Carrying Dangerous

Chemicals in Bulk

CHRIS Code Chemical Hazards Response Information System, published by the US Coast Guard EmS Emergency Schedules (to MFAG) ESD Valve Emergency Shutdown valve HLA High Level Alarm

IBC International Code for the Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk

ICS International Chamber of Shipping IEC International Electro technical Commission ILO International Labour Organization IMDG Code International Maritime Dangerous Goods Code IMGS International Medical Guide for Ships IMO International Maritime Organization ISGOTT International Safety Guide for Oil Tankers and Terminals ISM Code International Management Code for the Safe Operation of Ships and for

Pollution Prevention (the International Safety Management (ISM) Code)

LEL Lower Explosive Limit LFL Lower Flammable Limit MAC Maximum Allowable Concentration of a vapour MARPOL International Convention for the Prevention of Marine Pollution from Ships MFAG Medical First Aid Guide for Use in Accidents Involving Dangerous Goods

(Supplement to IMDG Code) MSDS Material Safety Data Sheet OCIMF Oil Companies International Marine Forum P&A Manual Procedures and Arrangements Manual PPE Personal Protective Equipment

MASSA M A R I T I M E A C A D E M Y GLOSSARY OF ABBREVIATIONS


ppm Parts per million PSA Pressure Swing Adsorption PTFE Tape Polytetrafluoroethylene tape, for sealing joints P/V Valve Pressure/Vacuum valve PVC Polyvinyl chloride RVP Reid Vapour Pressure SMPEP Shipboard Marine Pollution Emergency Plan SOPEP Shipboard Oil Pollution Emergency Plan SCABA Self-contained compressed air breathing apparatus SOLAS International Convention for the Safety of Life at Sea STET Short Term Exposure Limit STS Ship to Ship TLV Threshold Limit Values TLV –TWA Threshold Limit Values -Time Weighted Average TLV –STEL Threshold Limit Values -Short Term Exposure Limit TLV -C Threshold Limit Values –Ceiling TWA Time Weighted Average UEL Upper Explosive Limit UFL Upper Flammable Limit USCG United States Coast Guard VRP Voyage Response Plan (US requirement) VRU Vapour Recovery Unit WHO World Health Organization

MASSA M A R I T I M E A C A D E M Y AN INTRODUCTION TO SEA TRANSPORT OF CHEMICALS IN BULK Rev No: 0 Date: 20/07/2004 Page No: 1 of 3

BRIEF HISTORY OF THE TRADE Organic and inorganic chemicals were first synthesised on an industrial scale using coal, limestone, cellulose or molasses as raw materials in the early 1900s. The first petrochemical plants were developed in the United States in the 1920s, in tandem with the early oil refineries. Bulk shipment of liquid chemicals began in the mid-1940s using standard oil product tankers. At about the same time, some traditional cargo ships were equipped with deep tanks suitable for carrying vegetable oils as part of their liner cargo service. The first tanker to be specially designed to carry chemicals in bulk was the Marine Dow-Chem, a twin-screw steam turbine ship built in 1954 in the USA.

SS Marine Dow-Chem built 1954 in Quincy USA Since that time, the range of chemicals shipped in bulk has increased enormously and a special class of ships has been developed to meet this need -the chemical tanker. Most early chemical tankers were slightly modified product tankers, in which the main variation was coating of the cargo tanks. Although many of the products shipped could be carried quite safely in uncoated mild steel tanks, the need to maintain product quality, to minimise the potential for discoloration, and to facilitate tank cleaning between cargoes led to tank surfaces being coated with an impervious material. As the shipment of bulk chemicals developed, different countries involved with the trade developed regulations to minimise the risk to the ship, its crew and the environment, and applied them to their own ships and ships trading to their ports. These regulations were not all the same, and it was extremely difficult for a ship and its crew to comply with them all. To establish an


international standard for the safe design, construction and equipment of chemical tankers, IMO developed the Bulk Chemical Codes. It was a major step forward. A ship that complies with the1MO Codes is issued with a Certificate of Fitness that is recognised internationally, and enables the ship to trade worldwide carrying the cargoes for which it is approved. The cargoes now carried in these ships range from petrochemicals used as feedstock for plastics or synthetic rubbers and fibres, industrial acids and alkalis, alcohols and solvents, highly refined lubricating Oils and lubricating oil additives, to detergents, animal and vegetable oils, and edible products such as fruit juices or wine. Furthermore, certain refined petroleum products that were previously considered to be oils are now classified as chemicals under IMO marine pollution or toxicity regulations, and must only be carried by chemical tankers. CHEMICAL TANKER CARGOES Chemical tanker cargoes may be divided into four main groups: Petrochemicals. This is the collective name for organic chemicals derived from crude oil, natural gas and coal. Organic chemicals are those produced from living or once-living organisms, petroleum and natural gas (marine animals and plants) and coal (plants). It is now possible to synthesise organic chemicals from inorganic chemicals to the extent that 'organic chemicals' really means those compounds based upon the element carbon. But the term does not include the simplest carbon compounds such as carbon dioxide, carbon monoxide and the carbonates. Alcohols and carbohydrates. Alcohols may be derived from hydrocarbons or produced by fermentation. Vegetable and animal oils and fats. Derived from the seeds of plants and from the fat of animals and fish. Acids and inorganic chemicals. Inorganic chemicals are those that are not produced from living Or once-living organisms. However, a number of inorganic chemicals such as sulphur and ammonia can be manufactured using petroleum as the raw material. Acids may be organic or inorganic.


TYPES OF CHEMICAL TANKERS A modern chemical tanker is Primarily designed to carry some of the several hundred hazardous products now covered by the IMO Bulk Chemical Codes. The following general types of chemical carriers have developed since the trade began:

Sophisticated parcel chemical tankers: typically up to 40,000 tonnes deadweight with multiple small cargo tanks -up to 54- each with an individual pump and a dedicated pipeline, to carry small parcels of high grade chemicals. These ships have a significant proportion of the cargo tanks made with stainless steel, allowing maximum flexibility to carry cargoes that need their quality safeguarded. Product/chemical tankers: of similar size to parcel tankers but with fewer cargo tanks, mostly of coated steel rather than stainless, and less sophisticated pump and line arrangements. Such ships carry the less difficult chemicals, and also trade extensively with clean oil products. Specialised chemical carriers: small to medium sized ships, often on dedicated trades and Usually carrying a single cargo such as an acid, molten sulphur, molten phosphorus, methanol, fruit juice, palm oil or wine. Cargo tanks are coated or stainless, steel according to the trade.

MASSA M A R I T I M E A C A D E M Y HAZARDS AND PROPERTIES OF CHEMICALS


This chapter gives an introduction to the range of hazards normally associated with the properties of chemicals that are carried as cargoes, and the precautions necessary to minimise or avoid those hazards. 1.1 INTRODUCTION Chemical tankers are required to transport a wide range of different cargoes, and many tankers are designed to carry a large number of segregated products simultaneously. The operation of chemical tankers differs from any other bulk liquid transportation operations, in that on a single voyage a large number of cargoes with different properties, characteristics and inherent hazards may be carried. Moreover, in port several products may be handled simultaneously at one berth, typically including different operation such as discharge and loading as well as tank cleaning. Even the less sophisticated chemical tankers are more complex to operate than oil tankers. Transportation of bulk chemicals by sea not only requires specialist ships and equipment, but also specialist crew training, both theoretical and practical, in order for those involved to understand the characteristics of the various chemicals and be aware of the potential hazards involved in handling them. A particularly important aspect of this requirement is the provision of a data sheet, or cargo information form, giving details specific to a substance, to be held on board whenever that substance is carried by the ship (see Section 2.2). The following notes are only intended to indicate the most common characteristics and hazards of chemicals transported by sea in bulk. More detailed information on the main hazards and properties will be found in relevant chapters and appendices, where guidance is also given on the precautions to be taken. 1.2 FLAMMABILITY Vapour given off by a flammable liquid will burn when ignited provided it is mixed with certain proportions of air, or more accurately with the oxygen in air. But if there is too little or too much vapour compared to the air, so that the vapour-and-air mixture is either too lean or too rich, it will not burn. The limiting proportions, expressed as a percentage by volume of flammable vapour in air, are known as the lower flammable limit (LFL) and the upper flammable limit (UFL), and the zone in between is the flammable range (see Definitions for further details). Combustion of a vapour-and-air mixture results in a very considerable expansion of gases which, if constricted in an enclosed space, can raise pressure rapidly to the point of explosive rupture. In addition, a flammable liquid must itself be at or above a temperature high enough for it to give off sufficient vapour for ignition to occur. This temperature is known as the flash point. Some cargoes evolve flammable vapour at ambient temperatures, others only at higher temperatures or when heated. Safe handling procedures depend upon the flammability characteristics of each product. Non-combustible cargoes are those, which do not evolve flammable vapours. As mentioned, the fire risk presented by a flammable cargo depends upon the oxygen content of the atmosphere above it. By filling the ullage space in a cargo tank with an inert gas such as nitrogen or the output of an oil fired inert gas generator, the oxygen content can be reduced to a level at which the atmosphere will no longer support combustion of flammable vapour.



This is known as inerting a tank. But it is important to remember that an inerted atmosphere may become flammable again if air is admitted, for instance during routine measuring or on venting the mixture to atmosphere or during gas freeing with air (see Chapter 6 for guidance on cargo tank atmospheres). An inert atmosphere must not be considered as being without hazard; however, as without enough oxygen it will not support life either. Any person entering a tank, which has been inerted, must always follow strict procedures for entry into enclosed spaces (see Chapter 3). 1.3 HEALTH HAZARDS 1.3.1 Toxicity Toxic means the same as poisonous. Toxicity is the ability of a substance, when inhaled, ingested, or absorbed by the skin, to cause damage to living tissue, impairment of the central nervous system, severe illness or, in extreme cases, death. The amounts of exposure required to produce these results vary widely with the nature of the substance and the duration of exposure to it. Acute poisoning occurs when a large dose is received by exposure to high concentrations of a (short duration, i.e. a single brief exposure. Chronic poisoning occurs through exposure to low concentrations over a long period of time, i.e. repeated or prolonged exposures. Toxicity is objectively evaluated on the basis of test dosages under controlled conditions, and expressed as threshold limit values (TLVs). A full explanation is given in Appendix A. Prevention of exposure is achieved through a combination of cargo containment, which prevents toxic fumes or liquid from contaminating the workplace, and the use of personal protective equipment (PPE). The latter is described in Chapter 9. 1.3.2 Asphyxia Asphyxia is unconsciousness caused by lack of oxygen, and means suffocation. Any vapour may cause asphyxiation, whether toxic or not, simply by excluding oxygen in air. Danger areas include cargo tanks, void spaces and cargo pump rooms. But the atmosphere of a compartment may also be oxygen-deficient through natural causes, such as decomposition or putrefaction of organic cargo (see Appendix C), or rusting of steel in void spaces such as cofferdams, forepeak and after peak tanks. Precautions to be observed before entering these spaces are described in Chapter 3. 1.3.3 Anaesthesia Certain vapours cause loss of consciousness due to their effect on the nervous system. In addition, anaesthetic vapours mayor may not be toxic. 1.3.4 Additional health hazards Additional health hazards may be presented by non-cargo materials used on board during cargo handling. One hazard is that of frostbite from liquid nitrogen stored on board for use as atmosphere control in cargo tanks. Full advice on dealing with frostbite is contained in the MFAG (see



Definitions). Another hazard is that of bums from accidental contact with equipment used while handling heated cargoes. 1.4 REACTIVITY A chemical may react in a number of ways; with itself, with water, with air, with other chemicals or with other materials. 1.4.1 Self-reaction The most common form of self-reaction is polymerisation. Polymerisation generally results in the conversion of gases or liquids into viscous liquids or solids. It may be a slow, natural process, which only degrades the product without posing any safety hazards to the ship or the crew, or it may be a rapid, exothermic reaction evolving large amounts of heat and gases. Heat produced by the process can accelerate it. Such a reaction is called a run-off polymerisation that poses a serious danger to both the ship and its personnel. Products that are susceptible to polymerisation are normally transported with added inhibitors to prevent the onset of the reaction. See Appendix C for details. An inhibited cargo certificate should be provided to the ship before a cargo is carried. An example is shown in Appendix N. The action to be taken in case of a polymerisation situation occurring while the cargo is on board should be covered by the ship's emergency contingency plan. 1.4.2 Reaction with water Certain cargoes react with water in a way that could pose a danger to both the ship and its personnel. Toxic gases may be evolved. The most noticeable examples are the isocyanates; such cargoes are carried under dry and inert condition. Other cargoes react with water in a slow way that poses no safety hazard, but the reaction may produce small amounts of chemicals that can damage equipment or tank materials, or can cause oxygen depletion. 1.4.3 Reaction with air Certain chemical cargoes, mostly ethers and aldehydes, may react with oxygen in air or in the chemical to form unstable oxygen compounds (peroxides), which, if allowed to build up, could cause an explosion. Such cargoes can be either inhibited by an anti-oxidant or carried under inert conditions. 1.4.4 Reaction with other cargoes Some cargoes react dangerously with one another. Such cargoes should be stowed away from each other (not in adjacent tanks) and prevented from mixing by using separate loading, discharging and venting systems. When planning the cargo stowage, the master must use a recognised compatibility guide to ensure that cargoes stowed adjacent to each other are compatible. 1.4.5 Reaction with other materials



The materials used in construction of the cargo systems must be compatible with the cargo to be carried, and care must be taken to ensure that no incompatible materials are used or introduced during maintenance (e.g. by the material used. for replacing gaskets). Some materials may trigger a self-reaction within the product. In other cases, reaction with certain alloys will be non-hazardous to ship or crew, but can impair the commercial quality of the cargo or render it unusable. 1.5 CORROSIVENESS Acids, anhydrides and alkalis are among the most commonly carried corrosive substances. They can rapidly destroy human: tissue and cause irreparable damage. They can also corrode normal ship construction materials, and create a safety hazard for a ship. Acids in particular react with most metals, evolving hydrogen gas which is highly flammable. The IMO Codes address this, and care should be taken to ensure that unsuitable materials are not included in the cargo system. See Appendix B. Personnel likely to be exposed to these products should wear suitable personal protective equipment (see Chapter 9). 1.6 PUTREFACTION Most animal and vegetable oils undergo decomposition over time, a natural process known as putrefaction (going off), that generates obnoxious and toxic vapours and depletes the oxygen in the tank. Tanks that have contained such products must be carefully ventilated and the atmosphere tested prior to tank entry (see Chapter 3). It must not be assumed that all vapours produced by cargoes liable to putrefaction will in fact be due to putrefaction; some may not be obvious, either through smell or appearance of the cargo. Carbon monoxide (CO), for instance, is colourless and odourless and can be produced when a vegetable or animal oil is overheated. 1.7 PHYSICAL PROPERTIES 1.7.1 Specific gravity Cargo tanks on a chemical tanker are normally designed to carry cargoes of a higher specific gravity than an oil tanker. Sometimes the design strength even differs between tanks on the same ship. The information regarding tank strength may be found on the classification society's certification of the ship, and the master must be familiar with any restrictions that may be imposed on loading heavy cargoes. Especially important is the risk of slack loading a tank because this can lead to sloshing forces that may cause damage to the tank structure or its equipment. Likewise, the tank's design capacity must be strictly observed: exceeding it is dangerous. Note that the cargo's specific gravity and its vapour pressure must be considered together. 1.7.2 Vapour pressure and boiling point



At any given temperature every liquid exerts a pressure called the vapour pressure. The liquid will boil when its vapour pressure equals the external atmospheric pressure. In a closed cargo tank a liquid will boil when the vapour pressure is equal to the external vapour pressure plus the pressure setting of the pressure/vacuum (P /V) valve. The tanks and vent systems are designed to withstand this pressure, plus the hydrostatic pressure of the cargo. Cargoes that exceed the normal atmospheric pressure at 37.8°C (1000F) should not be loaded into a tank that is not specially designed for that duty. Where a p /V valve set point can be varied, the correct setting should be confirmed. Vent line systems must be checked for correct operation at regular intervals, as structural damage can easily result from malfunction or blockage due to freezing of cargo vapour, polymer build-up, atmospheric dust or icing in adverse weather conditions. Flame screens are also susceptible to blockage, which can cause similar problems. The higher the vapour pressure the more vapours will be released, a fact that may require use of personal protective equipment. 1.7.3 Freezing point Most liquids have a defined freezing or solidification point, sometimes described as the melting point. Some products, such as lubricating oil additives, vegetable and animal oils, polyols etc. do not have a defined point, but a freezing or melting range. For such cargoes, viscosity is used as a measurement of the product's liquidity or handling characteristics, and the term pour point is used instead. Cargoes with a freezing point higher than the ambient temperature of the ship's trading area will need to be heated in order to remain liquid. The structure and equipment of a ship normally impose a limitation on the carriage of heated cargoes. Exceeding this limitation could damage the tank coating or its structure. Excessive heat will also create thermal stresses, and the risk of cracking will increase. (Note that moderate heat increases steel strength; it is expansion forces that are the immediate limiting factor.) Caution should be exercised when carrying high heat products because cargo in non-insulated pipes and vents may freeze and clog the systems. Heating arrangements must be operated in accordance with design safety precautions; for example, pressures inside heating coils in tanks must be kept higher than the cargo pressure, and any interceptor tanks between heating return lines and the engine room must be checked regularly to detect any contamination. For certain cargoes, heating coils must be blanked off in accordance with IBC Code requirements. Uninsulated cargo pipes used for high heat products pose a further safety hazard, as they may cause severe burns if touched. 1.7.4 Cubic expansion Liquids will expand as temperature rises, or contract when temperature falls. Sufficient space must be allowed in the tank to accommodate any cubic expansion expected during the voyage. A useful formula is: Filling ratio (% full) = 100 (1 -RT) –S



where R = coeffic ient of expansion per °C (from cargo data sheet) T = expected maximum temperature rise in °C (during voyage) S = safety margin, usually 2% of tank capacity.

Vent line systems must be checked at regular intervals. Their design capacity is based on vapour flow only; structural damage may result if vent systems become full of cargo liquid due to thermal expansion. 1.7.5 Vapour density Vapour density is expressed relative to the density of air, as heavier or lighter. Most chemical cargo vapours are heavier than air. Caution must therefore be exercised during cargo operations, as vapour concentrations are likely to occur at deck level or in lower parts of cargo pumprooms. 1.7.6 Solubility Solubility is expressed in different ways: either as a simple yes or no, as slight, or as a percentage, but always in relation to water. Solubility is temperature dependant. A cargo with low solubility will form a layer above or below a water layer depending on its specific gravity. Most non-soluble chemicals are lighter than water and will float on top but some others, such as chlorinated solvents, are heavier and will sink to the bottom. Chemicals that are heavier than water can cause a safety risk in pumprooms when the overlying water is disturbed, and. in drip trays. Even in cargo tanks they may be trapped under water in pump wells, and pose a danger even after the tank atmosphere is tested and found safe for entry. 1.7.7 Electrostatic charging Certain cargoes are known as static accumulators, and become electrostatically charged when handled. They can accumulate enough charge to release a spark that could ignite a flammable tank atmosphere. The precautions necessary to prevent ignition from electrostatic charging are contained in Chapter 5, and a description of the phenomenon itself is given in Appendix D. 1.7.8 Viscosity The viscosity of a cargo determines how easy it is to pump, and the amount of residue that will be left after unloading. Viscosity is related to temperature and, in general, a substance will become less viscous at higher temperatures, but note that certain cargoes (such as luboil additives) show increased viscosity when heated. IMO standards define high and low viscosity substances, and require cargo tanks that have contained substances with a high viscosity to be pre-washed and the washings discharged to shore reception facilities.

MASSA M A R I T I M E AC A D E M Y CHEMICAL TANKERS


Chemical tankers

Many of the changes in everyday life that have taken place during the last fifty years have resulted from developments in the chemical industry. A wide range of ordinary items are in fact derived from complex chemical processes, and are often derived from the by-products of the production of energy. Some perfumes and medicines are derived from coal: from oil and gases we obtain fertilizers and plastics, weed killers and detergents, clothing and paints.

The greatest advances made in the chemical industry have been made in the last 25 years and one result has been a rise in the demand for raw materials. This in turn has led to a great increase in the maritime transportation of chemicals and the development of specialized ships in which to carry them.

The ships that have been built in response to this demand are among the most complex ever constructed. The cargoes they carry often present tremendous challenges and difficulties from a safety point of view and many chemicals are also a far greater pollution threat than crude oil.

Yet despite this, chemical tankers are among the safest ships afloat. One reason for this is the action taken by the industry and governments to adopt and implement stringent regulations regarding both safety and pollution prevention. The chemical trade

To most of us, chemistry seems to have little relevance to everyday life. In fact, the products of the chemical industry are all around us. Much of the food we eat is grown with artificial phosphate and nitrate fertilizers and protected with pesticide and herbicide sprays. Many of the clothes we wear are made of artificial fibres derived from various petrochemicals, which in turn may come from natural or petroleum gas. The same feedstocks can be used to produce weed killers, detergents for washing clothes and dishes, and anti- freeze for motor vehicle engines and artificial rubber. When we are ill we may turn to a patent medicine that comes from phenol, a derivative of coal. Almost every home contains toys, wire coating, packaging, records and other goods made from PVC, a versatile product that is derived from a combination of chemicals such as natural gas, oxygen, hydrochloric acid and common salt. And a modern world without plastics would be unthinkable.

The chemical industry has in fact transformed modern life and without it many of the products that we take for granted would never have been created. The raw materials for the chemical industry are almost as varied as its products and like any other raw materials have to be taken from where they are produced to where they are needed.



Much of this trade is carried out by ships, but the chemical trade is very different from other bulk shipping operations. In the first place, the tonnage involved is smaller. Crude oil is shipped in huge ships carrying up to half a million tons at a time. Chemicals are shipped in relatively small amounts. A crude oil tanker is usually dedicated solely to the carriage of crude oil. But a chemical carrier usually carries a variety of different products, all with different properties and, in many cases, presenting a multitude of difficulties and dangers.

The main chemicals carried in bulk can be divided into the following groups:

Heavy chemicals include substances that are produced in large quantities. Among the most common are: sulphuric acid, which is among the cheapest of all acids and can be produced from sulphur, air and water. It is also very versatile, being used for the production of phosphate fertilizer, explosives such as TNT, plastics such as rayon, purifying petroleum and removing oxides from metals and in storage batteries; phosphoric acid is used for the production of superphosphates and various other products, including detergents, paints, and foodstuffs: nitric acid is a basic ingredient of explosives, nitrate fertilizers and many dyes, and plastics; caustic soda is also shipped in liquid form. Others include hydrochloric acid, which is used in the steel reduction process and ore reduction, and ammonia.

Molasses and alcohols: molasses comes from either sugar beet or sugar cane and can be fermented into alcohols such as rum. Many alcohols are produced by the petrochemical industry, but some can also come from the fermentation of starch, such as ethanol. Alcohols of this type, including ethyl, methyl and propyl, are used in industrial processes (for example, to make cellulose acetate, which is a thermoplastic moulding compound used in the manufacture of telephones, buttons, films and many other products). Wines and some beers also come into this category and are being increasingly carried at sea in bulk quantities on ships that are in fact specialized chemical tankers.

Vegetable oils and animal fats: edible vegetable oils are derived from soya beans, groundnuts, cottonseed, sunflowers, olives, rape and other seeds. Coconut and palm oil can be used for cooking and also in the production of soap. Industrial oils come from linseed and castor seed. Some fats are extracted from animals including lard and fish oils. Oils and fats are in general esters of an alcohol (glycerol) and a variety of organic acids. Detergents and inorganics are common commodities which have been traded by sea for many years.

Petrochemical products form the most complex and probably the most versatile group of chemicals carried in bulk. They are all carbon compounds basically derived from oil or gas. They are extensively used in the production of fibre, artificial rubber and plastics and many are carried on liquefied gas carriers. Substances carried in chemical tankers include aromatics, such as benzene, which nowadays are derived mainly from oil but can be produced from coal. Other important petrochemicals include xylenes (used in the



production of polyester fibres); phenol (previously known as carbolic acid) and styrenes. But the number of different products is enormous and is growing all the time.

Coal tar products: coal tar is derived from the carbonization of coal. It can be converted into numerous products, many of which can also be produced from oil (oil and coal are both fossil fuels composed of hydrocarbons). The derivatives include benzene, phenol (used for the production of Bakelite, the first 'plastic'), naphthalene and many more. Common products which are derived from coal include nylon, aspirin, antiseptics and herbicides.

Chemical hazards and problems

As might be expected in a trade where the products are so varied, the hazards presented by chemicals vary enormously. The identification and evaluation of these hazards is of vital importance not only to the operation of chemical tankers but also to their design and construction.

Hazard evaluation of chemicals is in itself a complex problem stemming from the combination of the flammability and toxicity characteristics of the chemicals themselves as well as from design and operation hazards.

We can distinguish between the overall hazard to the environment and the intrinsic hazards of the chemicals. In respect of the former, the hazard rating profile developed by the Group of Experts on the Scientific Aspects of Marine Pollution (GESAMP), based on the release into the sea of noxious substances, falls into four main categories:

1 Damage to living resources

2 Hazards to human health

3 Reduction of amenities

4 Interference with other uses of the sea.

The main hazards and problems are listed below:

1 Cargo density the specific gravity of chemicals carried at sea varies greatly. Some are lighter than water. Others are twice as dense. Those substances which have especially high density include inorganic acids, caustic soda and some halogenated hydrocarbons.

2 High viscosity some lubricating oil additives, molasses and other products are



very viscous, especially at low temperatures. As a result they are sticky and move very slowly, causing problems in cargo-handling and cleaning.

3 Low boiling point

some chemicals vaporize at a relatively low temperature. This can causes containment problems, since when a liquid turns into a gas it expands, creating growing pressure. It is necessary, therefore, to provide either a cooling system or to carry the chemical in specially-designed pressure vessels.

4 Reaction to other substances

some chemicals react to water, to air or to other products. Measures therefore have to be taken to protect them. Apart from the fact that an accident can lead to a dangerous reaction (such as the emission of a poisonous gas) many chemicals can be ruined if they are contaminated by other substances. Methanol, lubricating oil additives and alcohols can be spoiled by even a slight amount of water contamination. Too much oxygen can lead to a rapid deterioration in the quality of some vegetable oils. Other products can change into a different product completely.

5 Polymerization some substances, such as petrochemicals, do not need to come into contact with another chemical before undergoing a chemical change - they are selfÄreactive and liable to polymerization unless protected by an inhibitor. This is a process whereby the molecules of a substance combine to produce a new compound. The process can be accelerated by catalytic factors such as heat, light and the presence of rust, acids or other compounds. Styrene, methyl methacrylate and vinyl acetate monomer are examples. Propylene oxide and butylene oxide are also liable to polymerization.

6 Toxicity many chemicals are highly poisonous, either in the form of liquid or vapour or both. The problem is sometimes made worse by the fact that toxicity can be increased when vapours from one substance come into contact with those from another.

7 Solidification some substances have to be kept at a high temperature, otherwise they solidify or become so viscous that they cannot easily be moved. Examples are some petrochemicals, molasses, waxes and vegetable oils and animal fats.



8 Pollution while many of the factors listed above present problems for the ship and crew, a considerable number of chemicals are extremely dangerous to marine and other forms of life. Although crude oil is probably the best-known pollutant of the sea, many chemicals are in fact far more poisonous and present a much greater threat - a threat which can be much more longÄlasting, since some of the chemicals concerned can enter the food chain and ultimately threaten humans as well as marine life.

It can be seen from the above list that chemicals present many difficulties to the shipowners and crew. A further complication is the fact that most chemicals are transported in relatively small amounts. The ships which carry them are consequently much smaller than crude oil carriers but are expected to carry several different products at the same time. It is probable that these products will have different and usually incompatible properties.

The development of the chemical tanker

The chemical tanker is basically a development of the last forty years. The development of the chemical industry in the United States following the end of World War II led to a demand for ships in which to carry the industry's products. A number of T2 tankers, mass-produced during the war, were converted by installing special tanks, double bottoms and suitable structural and piping arrangements.

Chemical carriers are smaller in size than crude oil carriers, but are

technically far more complex. These pictures show typical chemical carriers now in service. The 3,466 dwt Tina Jakobsen was built in Germany in 1980. An IMO Class 2 ship, she is fitted with 17 stainless steel tank.

The Bro Nora is owned by Sweden's Brostroms Shipping

Company. She was built in Spain in 1997. The 5,811 dwt ship has 13 stainless steel tanks.



The Norwegian flagged Kristin Knutsen is owned by Jo Tankers and

is built to IMO I, II and III standards. The 12,184-gt ship was built in 1998.

The C.T. Sun was built in 1980 and is owned by Sweden's Brostroms

group. She has a deadweight tonnage of 6,275 and operates in the North Sea and Baltic.

For the next decade or so tankers used in the carriage of chemicals were nearly all conversions. As the trade developed these ships became more refined, with the addition of tank linings, cofferdams and other features. The range of products carried in the first chemical tankers was relatively limited and the products themselves were not technically too demanding. The products also all tended to be owned by one company.

By the 1960s the chemical trade was becoming more complex. The number of substances being transported at sea was increasing rapidly - as was the total tonnage - and the products were technically more complicated. At the same time a growing number of what came to be called 'parcel tankers' were making their appearance. These were tankers designed to carry a range of chemical products for a number of different owners.

These ships were of necessity more complex than the original first-generation chemical tankers and during the early 1960s the first purpose-built chemical tankers made their appearance.

By the mid-1960s the chemical tanker had developed into a ship that was different from any other type, including other tankers. The cargoes carried by chemical tankers were probably potentially the most dangerous substances afloat, to the ships, their crews and to the marine environment. All of this made it imperative for something to be done to ensure that the ships themselves were suitable for the task.

From the outside some chemical tankers may look much like other tankers but in fact they are far more complicated (and ton for ton more costly). A crude oil carrier can afford to be big and ponderous because it normally carries one type of oil from one loading port to one destination on behalf of one shipper. A chemical tanker by contrast usually carries many different cargoes for a number of different customers and consequently has to be very versatile.

Despite their relatively small size (most are well under 50,000 dwt) chemical tankers normally have many more tanks than a bulk crude carrier - thirty or more is common. This gives greater flexibility and since the amount of individual cargoes carried are



usually small (most are under 500 cu m), the small size of the tank is not a disadvantage. The pipe work associated with the tanks is also extremely complicated, as are loading and unloading arrangements. All procedures involving the cargo have to be carried out with great care and precision, both to avoid cargo contamination and also to ensure that cargoes owned by different shippers are kept separate. Piping, monitoring and control equipment is all highly complex.

Ship construction also has to be of the highest possible standard. Tank cleaning is crucially important to cargo purity, so traditional stiffening inside the tanks is minimized. This enables the tanks to be cleaned more easily. The tanks have to be designed and constructed in such a way that stresses are avoided as far as possible since these can lead to fatigue cracks or damage to the tank coating. The design itself has to take into account the type of cargoes which are to be carried: some cargoes are more than twice as dense as sea water while others have to be carried at high temperatures to stop them solidifying. Both of these factors can affect the structure. Welding and other constructional features must be of the highest possible quality.

Chemical tankers make far greater use of cofferdams, double bottoms and similar devices than conventional crude oil tankers. To ensure that incompatible cargoes do not come into contact with each other, tanks are usually separated by a cofferdam - a space between the two tank walls.

Most chemical tankers have their tanks separated from the outer frame of the ship by a double bottom or double skin. If the ship is damaged in a collision or a grounding this space should protect the cargo tanks from damage.

The tanks of a chemical tanker are constructed of special. materials, all designed to carry certain products. The early chemical tankers generally had tanks made of stainless steel which resists corrosion from many products and could be cleaned relatively easily. But stainless steel is unsuitable for many chemicals and so different coatings were designed. Typical coatings in use nowadays include epoxy, phenolic resins, zinc silicate, polyurethane and rubber. Each one has advantages and disadvantages and so far no coating has been developed which is suitable for all chemicals.

As a result, most chemical tankers, especially parcel tankers, will have tanks lined with a number of different coatings (as well as some made of stainless steel) to enable it to carry as wide a range of products as possible. Some of the coatings in use today are listed below:

Suitable Unsuitable Comments Epoxy Alkalis, glycols,

seawater, animal fats, vegetable oils

Aromatics e.g. benzene, toluene, ethanol, methanol

Some coatings can pick up product traces



Phenolic resins Strong solvents, polyurethanes

Better resistance than epoxy, but costs more

Zinc silicate Aromatic hydrocarbon solvents, e.g. benzene,toluene, alcohols, ketones

Acids, alkalis, seawater. Most vegetable oils and animal fats

Moisture in tank can result in some halogenated compounds reacting with cargo to produce acids which damage coating

Polyurethane All cargoes, suitable for epoxy coatings, some compatible with zinc silicate

Has smooth finish which cleans more easily than epoxy Water soluble cargoes should not be followed by water until coating has been dried

Rubber lining Highly corrosive substances, e.g. phosphoric acid; hydrochloric acid

Stainless steel Sulphuric acid, nitric acid, phosphoric acid, caustic soda (up to certain temperatures only), wine

Different grades of steel are used. Corrosion does occur but can usually be monitored. Seawater is especially corrosive so care must be taken in tank washing

Chemical tanker safety

The subject of chemical tanker safety was first raised at the international level in the mid-1960s. and it was agreed that the whole matter should be discussed by the International Maritime Organization’s Maritime Safety Committee (IMO's senior technical body) in March 1967.

The MSC duly did so and agreed that a new sub-committee be established dealing with ship design and equipment. It should 'consider as its initial task the construction and equipment of ships carrying chemicals in bulk.' The new sub-committee held its first session in January 1968 and agreed to prepare a code to cover the design criteria, construction and equipment of chemical tankers.

The Code for the Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk (BCH Code)

The new code was applied to ships built on or after 12 April 1972 and its purpose was given in a preamble which states: 'This Code has been developed to provide an agreed international standard for the safe carriage by sea of dangerous chemicals in bulk by



prescribing the constructional features of ships involved in such carriage and the equipment they should carry with regard to the products involved.'

The Code was not, in its original form, concerned with pollution aspects. IMO was fully aware of the threat which chemicals posed to the marine environment, but had decided to consider this aspect in the context of a new international convention on marine pollution which was then being prepared. This was ultimately adopted in 1973 as the International Convention for the Prevention of Pollution from Ships (MARPOL), Annex II of which is concerned with the prevention of chemical pollution.

The basic philosophy of the code is to classify each chemical according to the hazard they present and to relate those hazards to the type of ship in which they are carried: the more dangerous the chemical the greater is the degree of cargo protection and survival capability required. The hazards considered in the new Code were:

(a) Fire hazard defined by flashpoint, boiling point, explosion limit range and auto-ignition temperature of the chemical.

(b) Health hazard defined by:

(i) irritant or toxic effect on the skin or to the mucous membranes of the eyes, nose, throat and lungs in the gas or vapour state combined with vapour pressure

(ii) irrational effects on the skin in the liquid state

(iii) toxic effect via skin absorption

(c) Water pollution hazard defined by human toxicity, water solubility, volatility, odour or taste, and specific gravity.

(d) Air pollution hazard defined by:

(i) emergency exposure limit

(ii) vapour pressure

(iii) solubility in water

(iv) specific gravity of liquid



(v) relative density of vapour

(e) Reactivity hazard defined by reactivity with:

(i) other chemicals

(ii) water

(iii) the chemical itself (including polymerization) Three ship types are specified in the Code.

•

Type I ships must be able to survive assumed damage anywhere in their length. Cargo tanks for the most dangerous products should be located outside the extent of the assumed damage and at least 760mm from the ship's shell. Other cargoes, which present a lesser hazard may be carried in tanks next to the hull.

•

Type II ships, if more than 150m in length, must be able to survive assumed damage anywhere in their length; if less than 150m, the ship should survive assumed damage anywhere except when it involves either of the bulkheads bounding machinery spaces located aft. Tanks for Type II cargoes should be located at least 760mm from the ship's shell and outside the extent of assumed grounding damage.

•

Type III ships, if more than 125m in length, should be capable of surviving assumed damage anywhere in their length except when it involves either of the bulkheads bounding the machinery space. If less than 125m in length, they should be capable of surviving damage anywhere unless it involves machinery spaces. There is no special requirement for cargo tank location.

If the ship is intended to transport more than one substance, the requirements for ships' survival correspond to the most dangerous substance, but the cargo containment requirement need only conform to the specified minimum requirements for the chemicals taken individually.

Within the ship itself other factors vary according to the hazard prescribed, such as tanks, tank vents, tank environmental control systems, electrical instruments, vapour detectors and fire protection. The Code contains seven chapters, the first of which covers general matters such as application, definitions, surveys and certification.



The BCH Code was developed in a relatively short space of time and it was recognized in 1971 that it was far from being the last word on the subject. The preamble to the original version says that IMO intended to either extend the code or adopt other codes to cover hazardous gases in bulk (in the event a separate code was developed); that the subject of the cargo size limitations warranted consideration; and that the section on fire protection was incomplete; and that the section dealing with electrical requirements needed to be re-examined. Work on improving the Code came to be a continuous process. Between 1972 and 1983 no fewer than ten sets of amendments were adopted, enabling the Code to be improved in many areas and to keep abreast of technical developments.

The Bulk Chemical Code, like other instruments adopted by the Assembly, is only a recommendation. There was no obligation on governments to adopt it in whole or even in part. In practice, however, the vast majority of chemical. tankers constructed since the Code was adopted were built in accordance with its requirements.

Preventing pollution by chemicals: Annex II of MARPOL

The International Convention for the Prevention of Pollution from Ships, 1973/1978 (MARPOL 73/78)[1] is the most important international treaty dealing with marine pollution ever adopted. Its technical provisions are contained in five annexes dealing with different pollutants. Annex II deals with pollution by noxious liquid substances carried in bulk.

These substances are divided into four categories, graded A to D according to the danger they present to the marine environment.

1 Category A Noxious liquid substances which if discharged into the sea from tank cleaning or deballasting operations would present a major hazard to either marine resources or human health or cause serious harm to amenities or other legitimate uses of the sea and therefore justify the application of stringent antiÄpollution measures. Examples are acetone cyanohydrin, carbon disulphide, cresols, naphthalene and tetraethyl lead.

2 Category B Noxious liquid substances which if discharged into the sea from tank cleaning or deballasting operations would present a hazard to either marine resources or human health or cause harm to amenities or other legitimate uses of the sea and therefore justify the application of special anti-pollution measures. Examples are acrylonitrile, carbon tetrachloride, ethylene dichloride and phenol.

3 Category C Noxious liquid substances which if discharged into the sea from tank cleaning or deballasting operations would present a minor hazard to either marine resources or human health or cause minor harm to amenities or other legitimate uses of the sea and therefore require special operational conditions. Examples are benzene, styrene, toluene and xylene.



4 Category D Noxious liquid substances which if discharged into the sea from tank cleaning or deballasting operations would present a recognizable hazard to either marine resources or human health or cause minimal harm to amenities or other legitimate uses of the sea and therefore require some attention in operational conditions. Examples are acetone, phosphoric acid and tallow. As far as the safety side was concerned, the position of the BCH Code was ambiguous. Although only a recommended instrument, it provides for the issuing of a Certificate of Fitness. Several countries require that ships entering their ports should possess this Certificate, even if they come from countries where the Code has not been implemented. As far as these countries are concerned, the Code has in effect been given convention status.

On the pollution side, the situation was rather different. Annex II dated back to the early 1970s and by the end of the decade was becoming outdated as a result of continuing technical developments. MARPOL 1973 had not entered into force, but in 1978 IMO convened a conference on tanker safety and pollution prevention. This adopted a protocol to MARPOL, which made major changes to Annex I and in effect absorbed the parent convention.

At the same time, it was recognized that there were a number of technical difficulties connected with Annex II which had still not been solved. To give Governments and the industry time to solve these problems it was agreed at the 1978 conference that implementation of Annex II should be deferred for three years after the entry into force of Annex I. On both the safety and pollution front, therefore, there were problems which needed to be tackled by IMO.

The 1983 amendments to SOLAS

There was general agreement within IMO that the ambiguous position of the BCH Code should be ended by making the Code a mandatory instrument and that the simplest way of doing this would be by inserting an appropriate amendment into Chapter VII of the SOLAS Convention (which deals with the carriage of dangerous goods).

At the same time it was decided that the Code itself should be further improved by bringing it into line with another Code which had been developed by IMO to deal with the construction and equipment of ships carrying liquefied gases in bulk. This was adopted in 1975, four years after the BCH Code, and was regarded as more detailed and completes.

The result was the adoption in 1983 of a new code, the International Code for the Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk (IBC Code). The Code contains the provisions of all ten sets of amendments to the original BCH Code, together with other improvements (such as a chapter on ships engaged in



incineration at sea). It was agreed that the new Code would only apply to new ships (had it been made retroactive, owners of existing chemical tankers would have been faced with enormous conversion costs).

The new Code was adopted by the Maritime Safety Committee in 1983 and it was agreed that it would apply to ships of any size built on or after 12 July 1986. Existing ships would still be covered (voluntarily) by the original BCH Code.

Amendments to Annex II of MARPOL 73/78

While the MSC was working on the new IBC Code and the SOLAS amendments, IMO’s Marine Environment Protection Committee was tackling the problems associated with chemical pollution.

It had two principal objectives. The first was to amend Annex II of MARPOL 73/78 and remove the many problems associated with its implementation. The second was to modify the new IBC Code and the existing BCH Code so that they dealt with pollution aspects as well as safety.

A major problem with the implementation of Annex II arose from the original premise on which it was drafted, namely that the quantity of Category B or C chemicals remaining in a tank after unloading could be calculated using vertical and horizontal surface areas and the relevant physical properties of the substance at the temperature concerned, e.g. specific gravity and viscosity. Providing this calculated quantity was less than the upper limit established by the Convention this residue could be discharged into the wake of the ship with the proviso that the resultant concentrations in the sea did not exceed a certain limit. The application of the latter criteria required further calculations to establish a suitable speed and the under-water discharge rate for the chemical concerned. The operation of a chemical carrier with parcels of different chemicals and considerable variability of physical properties and ambient temperature conditions would mean that a member of the ship's crew would be employed virtually full- time in computing residue quantities and ascertaining discharge parameters.

Experience indicated that the complicated procedure described above could be circumvented if the efficient stripping of tanks to a relatively insignificant residue level during unloading was made mandatory. Those smaller quantities of residues could then be discharged overboard without limitation or rate of discharge, etc.

The main purpose of the amendments to Annex II adopted in December 1985 was to introduce new pollution control provisions based upon efficient stripping of tanks.

Another major problem of Annex II concerns reception facilities, the provision of which is crucial to the effective implementation of the regulations. Reception facilities for chemicals are more expensive and complicated than those designed for the reception of oily wastes, since the wastes they are required to deal with are much more varied. There



is also little opportunity for recycling them (as can be done with some oily wastes). As a result, governments and port authorities have been reluctant to provide such facilities, particularly as the Convention itself was ambiguous as to whether the facilities should be provided in loading or unloading ports.

There have been difficulties with some other aspects as well, such as developing monitoring equipment to ensure that chemicals are properly diluted before being discharged into the sea. Therefore certain operational procedures had to be developed to limit the discharge rate to minimize harm to the environment.

In 1983 the IMO Assembly had adopted procedures and arrangements for the discharge of noxious liquid substances which are called for by various regulations of Annex II and these were applied on a trial basis by a number of IMO Member States. These trials showed a number of difficulties in implementing Annex II, mainly associated with the problems already outlined in the previous paragraphs. They included:

1. The requirements were too complex and put a heavy burden on the crew of the ship. 2. Measures of control were very limited and compliance with the standards depended entirely upon the willingness of the crew. 3. There is a general lack of facilities for the reception of chemical wastes. Although provision of facilities themselves did not present great difficulties because the amount is smal compared with oily wastes, treatment of wastes and ultimate disposal was (and still is) a problem.

The tests confirmed what many authorities had already suspected and much of MEPC's work has subsequently been directed towards improving tank unloading requirements and at the same time minimizing the need for reception facilities.

Years of work by the MEPC bore fruit in December 1985 when a special session of the Committee adopted the long-awaited amendments to Annex II. The amendments are designed to encourage shipowners to improve cargo tank stripping efficiencies, and they contain a number of specific requirements that will ensure that both new and existing chemical tankers reduce the quantities of residues to be disposed of. As a result of adopting these requirements it was possible to adopt simplified procedures for the discharge of residues; furthermore, the quantities of categories B and C substances that will. be discharged into the sea have been reduced.

The IBC Code applies to all chemical tankers constructed after 1 July 1986. The BCH Code applies to other "existing" ships. The importance of the two codes is that they are concerned with carriage requirements, including the way the cargo is protected from the consequences of an accident. MARPOL's Annex II is concerned only with discharge requirements.



The two instruments are thus complementary: MARPOL is designed to prevent pollution resulting from routine operations, while the Codes help to reduce pollution resulting from accidents. Since then, work has continued on developing measures to implrove the safety of checmial carriage at sea. In 1992, IMO agreed to review all the provisions in Annex II of MARPOL, with the aim of simplifying the requirements to encourage more widespread implementation of the Annex. At the same time, it agreed to review the categorization system.The decision to completely review the Annex was influenced by a number of developments.

Firstly, improvements in ship technology meant that stripping of tanks had improved to the extent that only very minimum amounts of residues would be left in tanks after unloading and consequently the limits on the discharges of substances could also be drastically cut. As improvements in technology have enabled IMO to reconsider the amount of discharge permitted to enter the marine environment, they have also provided an opportunity to reconsider the number of defined pollution categories.

Another issue was increased understanding of the environmental impact of chemicals on the marine environment. In the existing product categorization, Annex II placed considerable emphasis on acute aquatic toxicity, tainting of fish and bioaccumulation with associated harmful effects, but it was being recognized that other properties were equally important - such as chronic aquatic toxicity, and the effect on wildlife or seabed of substances that would sink or persistently float on the surface.

The 1992 UNCED Rio Conference also influenced the review of Annex II. Chapter 19 of Agenda 21 adopted by the Conference included a programme on harmonization of classification and labelling of chemicals and the United Nations Committee of Exerts on the transport of Dangerous Goods and the Organization for Economic Cooperation and Development (OECD) have been acting as clearing houses for the development of harmonized hazard classification systems covering the physical and biological properties that affect safety and protection of the environment.

The work of these organizations in developing harmonized classification systems has a bearing on the work of the GESAMP Evaluation of Hazardous Substance working Group - and on the work of the Working Group on the Evaluation of Safety and Pollution Hazards (ESPH) - a working group of the IMO Sub-Committee on Bulk Liquids and Gases (BLG), which reports to the MEPC and MSC. The ESPH working group is dealing primarily with the assignment of pollution categories and carriage requirements for products in order to ensure their safe carriage and protection of the marine environment.

As instructed by the MEPC, the ESPH working group is considering whether the existing five product category system in Annex II (categories A, B, C, D plus "other liquid substances") could be simplified into a three-category system. The three-category system is based on the premise - in line with the development of the so-called precautionary approach[2]



- that no product should be permitted to enter the sea in unlimited quantities, as is the case with Category D and "other liquid substances" under Annex II. Therefore these two categories could be combined, creating a category for substances with limited restrictions.

A second category could combine current categories B and C, since ship technology now makes it easier for all ships to achieve minimum residue levels of 100 litres per tank - so there is no need to differentiate.

The third category would be equivalent to the existing Category A - in other words, substances considered highly environmentally hazardous and which should not be discharged at all. It is envisaged that the complete revision of Annex II will be completed by 2002. By then, hazard profiles for all noxious liquid substances carried in bulk on ships which come under MARPOL Annex II will have been re-evaluated and re-categorized. This is a mammoth task - some 300 substances are listed in the International Bulk Chemical Code. The MEPC is also looking into the whole issue of reception facilities and how to ensure adequate reception facilities are provided at ports.



Noxious liquid substances carried in bulk - examples[3]

Heavy chemicals

Those substances produced in large quantities, for example:

sulphuric acid - among the cheapest of all acids and can be produced from sulphur, air and water. It is also very versatile, being used for the production of phosphate fertilizer, explosives such as TNT, plastics such as rayon, purifying petroleum and removing oxides from metals and in storage batteries;

phosphoric acid - used for the production of superphosphates and various other products, including detergents, paints, and foodstuffs: nitric acid - a basic ingredient of explosives, nitrate fertilizers and many dyes, and plastics;

caustic soda is also shipped in solution;

hydrochloric acid - used in steel reduction process and ore reduction;

ammonia.

Molasses and alcohols

Molasses comes from either sugar beet or sugar cane and can be fermented into alcohols such as rum.

Many alcohols are produced by the petrochemical industry, but some can also come from the fermentation of starch, such as ethanol. Alcohols of this type, including ethyl, methyl and propyl, are used in industrial. processes (for examples to make cellulose acetate, which is a thermoplastic moulding compound used in the manufacture of telephones, buttons, films and many other products).

Wines and some beers also come into this category and are being increasingly carried at sea in bulk quantities on ships which are in fact specialized chemical tankers.



Vegetable and animal fats and oils

Edible vegetable oils are derived from soya beans, groundnuts, cottonseed, sunflowers, olives, rape and other seeds.

Coconut and palm oil can be used for cooking and also in the production of soap.

Industrial oils come from linseed and castor seed.

Some fats are extracted from animals including lard and fish oils.

Petrochemical products

The most complex and probably the most versatile group of chemicals carried in bulk - all are carbon compounds basically derived from oil or gas. They are extensively used in the production of fibre, artificial rubber and plastics and many are carried on liquefied gas carriers.

Substances carried in chemical tankers include aromatics, such as benzene, which nowadays are derived mainly from oil but can be produced from coal.

Other important petrochemicals include xylenes (used in the production of polyester fibres); phenol (previously known as carbolic acid) and styrenes.

Coal tar products

Coal tar is derived from the carbonization of coal. It can be converted into numerous products, many of which can also be produced from oil (oil and coal are both fossil fuels composed of hydrocarbons).

Coal tar derivatives include benzene, phenol (used for the production of Bakelite, the first 'plastic'), naphthalene and many more.

Common products which are derived from coal include nylon, aspirin, antiseptics and herbicides.

[1] Link to the Focus paper on MARPOL. [2] The precautionary approach was introduced into the 1996 protocol to the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter (LC), and



is based on the premise that unless a substance can be proved to be harmless, it should not be dumped in the sea. Previously, the onus has been to prove something is harmful, to get its dumping banned. [3] Each individual product is evaluated according to the hazards it presents.

MASSA M A R I T I M E AC A D E M Y SAFETY IN CHEMICAL TANKERS


DANGER can always be present in a Chemical Tanker. Most of the risks have been removed by the Designer. Other risks can be avoided by TAKING CARE, and by strictly following the instructions of your officers. Your officers have been trained in the proper operating procedures. EVERYONE on board must TAKE CARE. This includes YOU. To be able TO AVOID RISKS you must know what they are. This booklet warns you of the risks. It tells you about the types of cargoes you may carry, and their characteristics. It tells you how you can TAKE CARE. Terms are explained as we go along. If you already understand the terms, please be patient -your shipmates may not understand them. Chemical Tankers are much more complicated than ordinary tankers. They usually have more tanks, more valves, more pumps, more blanks, more lines. They may have on board many different kinds of cargo at the same time. These cargoes may be bulk liquid chemicals, solvents, lubricating oils, vegetable and animal oils, petroleum products, and other such liquids. They can be handled safely. Care is absolutely essential -throughout the whole operation. Not all the cargoes are dangerous, but most of them will have some HAZARD connected with them. You must follow standing instructions at all times, whether or not the cargo is dangerous. You must know about the cargoes your ship carries. This way you and your ship will always be safe.



Hazards from Ignition Sources Chemical tankers have many hazards; the precautions to be taken for their particular characteristics will be found in pages sixteen to twenty five. The preceding pages outline some of the more general precautions to take. Know them. Obey them. Be aware of the particular characteristics of flammable and toxic vapours. They can kill. Flammability Hazards Many of the cargoes you will carry are FLAMMABLE. That means

that they can be set on Fire. Or perhaps they give off vapours or gases, which can be set on Fire. Fire is a major hazard and all precautions to avoid it must be taken. We will look at the properties of chemical cargoes later on. But fire is one very important reason why you should only SMOKE WHERE SMOKING IS ALLOWED.

Smoking Obey ALL instructions about smoking. The Captain will say where smoking is allowed. NEVER smoke outside on the open deck, Smoking can be very dangerous. Secret smoking is more dangerous than controlled smoking. There may be flammable gases in a toilet or locker (for instance) Gas may have been drawn into the accommodation through the ventilation system. A crafty smoke could be dangerous. Smoking in bed is foolish anywhere. It is dangerous in any ship. It could be disastrous in a Chemical Tanker.

Lighters Cigarette lighters are not allowed on board. If a cigarette lighter were to fall on deck it might operate. If you have a cigarette lighter, hand it to the Captain who will keep it in his safe until you leave the ship.

Matches You should only use SAFETY MATCHES. Other kinds of matches are a MENACE onboard Never carry matches on your person when working on the cargo deck You still must take care even with safety matches. Under certain conditions even safety matches can ignite.

Torches Ordinary hand-torches (flashlights) can cause small sparks capable of setting fire to flammable vapour. You must only use the specially made torches (which are called APPROVED SAFE TORCHES) and which are supplied for your use by the officers onboard your ship.

Domestic Equipment Domestic equipment which can cause small sparks and set fire to Equipment flammable vapour include: -

• Shavers • Radios • Electric cooking appliances

You must keep your electric shaver and radio in your cabin. Never take a radio or other portable electric appliance out onto the open deck.



More Hazards from Ignition Sources If there is any possibility of flammable vapours entering galleys or the accommodation: -

• DO NOT SMOKE • DO NOT USE FIXED OR PORTABLE ELECTRIC APPLIANCES

Aluminium If aluminium or one of its alloys is knocked against rust heat may be

generated. The heat can be enough to ignite a flammable mixture. Never drag aluminium or light metal objects across decks. Never take portable equipment made of aluminium or its alloys into -

• Cargo tanks • Pump rooms • Any space where flammable mixtures may accumulate

When removing scale or sludge never use scoops or shovels made of aluminium or aluminium alloy.

Aluminium Paint Aluminium paint over rust may be just as dangerous. If it is struck or rubbed the same heat may be generated. Never allow heavy objects to strike rusty areas, which are covered with aluminium paint.

Rubbish Dirty waste, rags, sawdust and other rubbish is DANGEROUS if left lying about. Heat may be generated within bundles of rubbish. The heat may be enough to ignite flammable mixtures. It may become hot enough to set itself on fire. The risk is increased if material is left near steam pipes. Clear away all waste, rags, sawdust etc. after use.

Cathodic Protection Some ships tanks are fitted with cathodic protection. This is a method of controlling corrosion. Metal slabs known as anodes are fitted into tanks. They are on supports. If an anode or its support is struck or dislodged a spark may result. Never knock anodes or their supports in tanks.

Hand Tools Metal hand tools could cause sparks by: - • Striking together • Striking against other metal • Being dropped

"Non-sparking" tools could be hazardous as ferrous metals (which can spark) might become imbedded in the material. In any area where there may be explosive vapour: -

• prevent metal hand tools from knocking together • prevent metal hand tools from striking other metal • prevent metal hand tools from being dropped • lower metal hand tools into tanks in a canvas bag or bucket • do not use so called "non-sparking" tools



Electric Tools Electric tools and appliances used in tank cleaning and gas-freeing can produce sparks :-

• If they are not of approved design • If they are defective

When tank cleaning or gas-freeing using portable equipment: - • use only approved type • report any defects in this equipment

Static Electricity and Tank Cleaning

Under certain circumstances STATIC ELECTRICITY may be generated in a tank. This can happen in several ways, but it results in the atmosphere in the tank becoming charged with electricity. This in itself is not dangerous, as the electricity can find earth through the ship's hull. However, while the electricity (or charge) remains in the tank, a spark -capable of igniting a flammable mixture or vapour -can be produced by introducing a metal object into the tank. Objects, which have caused electrical discharges, resulting in sparks and thence Explosion, include -

• Hand held metal ullage tapes • Metal sampling cans • Metal sounding rods • Unbonded portable washing machines

None of these things should be introduced into a tank unless you are told to do so by an officer. The officer will know whether or not the article is properly earthed. A material, which conducts electricity, is known as a CONDUCTIVE material or a CONDUCTOR. When a liquid, which is above its flash point, is being loaded into gas-free tanks the following must be made of non-conductive material -

• hand held metal ullage tapes • metal sampling cans • metal sounding rods

Flammable gas remains in a tank after the cargo is discharged. This represents a hazard particularly during washing -unless appropriate steps are taken. When tank washing is in progress -

• Keep tank openings closed as much as possible • Do not introduce metal objects into the tank, unless it is an earthed washing machine. • Do not disconnect tank cleaning hoses from their hydrants (or connections) until they

have been removed from the tank. This ensures that they remain earthed until they are clear of the dangerous atmosphere



• Do not leave tools or metal objects lying around the tank deck which could be accidentally introduced into the tank.

Flammable and Toxic Vapours

Presence of Gas There may be flammable or toxic gas -

• after loading or discharging volatile or toxic cargo • after loading any cargo into a tank which is not GAS FREE

Gas-Free N.B. A space declared GAS-FREE is free of gas at the time of the test. The space may not remain gas free and safe. Frequent tests are advisable. There may be flammable or toxic gas :-

• if flaking tank coating material is disturbed • after a heating coil is opened up • when a pipeline or valve is opened up • when a cargo pump or valve is opened up • when a cargo vent line is opened up • whenever cargo residue is present and particularly when it has

been disturbed, e.g. behind tank coating blisters or imperfections.

In Other Spaces Flammable or toxic gas may be in a space into which flammable or toxic cargo may have leaked. Examples are -

• pump rooms • cofferdams • ballast tanks • double bottom tanks • empty compartments next to tanks used to carry these cargoes

Before you open a tank any pressures must be relieved. This has to be done very carefully -under controlled conditions. Openings must be closed as soon as possible.

A space which is shown by test instrument to be free of flammable or toxic gas is stated to be GAS FREE. A space may be certified gas free and be -

• safe for men and cold work • safe for hot work

Cold work includes work which can cause sparks or enough heat to ignite any nearby vapour -e.g. hammering.



Hot work is so hot that it can actually cause dirty parts of the tank to give off vapour -e.g. welding. This vapour can be ignited due to the work. Tests for the presence of flammable, or toxic gases will be carried out by a responsible officer. Chemical tankers carry instruments, which will indicate -

• the presence of gas given off by the various toxic cargoes • the presence of flammable gas given off by volatile cargoes • the percentage of oxygen in the air

Remember that a space may contain - • toxic or poisonous gas • flammable gas or vapour • air without enough oxygen to Support life

More about Vapour

Dispersion Many vapours are heavier than air. After they escape from tank

openings or vents during loading they will tend to lie around the decks. From there they can enter doors and openings near the cargo deck. They may be drawn into machinery spaces and air conditioning intakes. Winds moving at about 5 miles per hour or less cause little air movement. Little air movement means great danger. Flammable or toxic mixtures may not disperse. They may lie about at some distance from where they arise. Quite rich concentrations can, however. be dispersed by quite gentle breezes. Complete and rapid dispersion requires a clear path for the air.

Eddies If you watch a river flowing past the support for a bridge you will see currents swirling in behind the support on the, downstream side. Moving air behaves in the same way. Air flowing swiftly past the superstructure swirls around it. This happens especially on the lee side. The passing air causes a slight drop in pressure. Some of the moving air is drawn in, in swirling currents. These currents are known as eddies. During cargo operations a wind blowing may -

• contain flammable or toxic vapour • form eddies containing flammable or toxic vapours • deposit flammable or toxic gas near the superstructure

These gases may be carried through openings into galleys, accommodation, deck lockers etc.

Vapour must be excluded from galleys. If this cannot be done, electric galley equipment must not be used.



Vapour must be kept excluded from machinery spaces. Flammable gases must be kept from all sources of ignition in machinery spaces. Generally, during cargo operations, auxiliary machinery will be in use on the ship. In certain weather conditions (e.g. if there is fog and no breeze) it may not be possible to guarantee that vapour will not enter the machinery spaces. In these circumstances, cargo work must be stopped until the weather conditions change. Whenever large amounts of vapour accumulate around the deck, cargo work must be suspended. During cargo operations, or whenever dangerous vapour may be present around the decks-

• strictly obey orders regarding closing doors and ports • strictly carry out orders regarding ventilation and air intakes • keep all windows and ports closed

DO REMEMBER EDDIES • where they. form depends upon wind force and direction • a wind blowing from forward to aft may help vapour to accumulate aft of any

superstructure in its path • a wind blowing across the ship will tend to deposit gas on the lee side.

Pollution

Spillage Cargo spilled can be dangerous. It can often evaporate quickly. Toxic vapours may be released in large quantities. Flammable mixture may form rapidly. The sea and air may become polluted.

Hoses and Connections Defective hoses can cause spillage. Defective or badly made connections are dangerous. Sudden strain on hoses can cause -

• Defective hoses • Defective connections

Carelessly stowed gear is potentially defective gear. Always check cargo gear for defects before it is used Report all defects to your Officers. Report any leakage to your Officers.

Pollution Of course, pollution is not a personal hazard, or a source of risk to the ship. At least we might not think so at first sight. In fact, it is a very real threat to the lives and livelihood of all of us. Even relatively small quantities of some chemicals discharged into the sea -particularly in coastal waters -can have a terrible effect on human and marine life in the area. LIFE MAY HAVE STARTED IN THE OCEAN -DO NOT LET IT END THERE



To prevent pollution - Do not use hoses, which appear defective. Avoid bending flexible hoses excessively. Hoses should be suspended from suitable equipment. Hoses should never be allowed to chafe. Great care must be taken to tend the moorings on a chemical carrier, to avoid straining or breaking the hoses or connections.

Should a cargo connection leak -

• Report immediately to the officer in charge who will effect remedial action. • Do not attempt to stop cargo operations by yourself . • Do not close any valve in the loading system and do not operate any shut-off

device. During loading and discharging -

• All scuppers must be suitably plugged • A regular check must be kept for signs of leakage



Precautions when entering spaces Entry into Enclosed Spaces

Many spaces on the ship may be dangerous to enter. This is because -

• they have contained flammable mixtures • they have contained toxic gas • they are adjacent to spaces containing dangerous cargoes,

which may have leaked into them in either liquid or gaseous form

• there may be insufficient oxygen, in the air in the space, to support life.

Before entering any enclosed space - • obtain permission from the officer in charge • the officer in charge must check the atmosphere in the space

for the presence of gas and for the lack of oxygen with the appropriate equipment

• make sure that there is someone outside the space, at the entrance, to keep watch and to raise the alarm if you get into difficulty

• ensure that the ventilation equipment is working have a lifeline, harness and breathing apparatus ready for use at the entrance to the compartment

ALWAYS BE FAMILIAR WITH THE TYPE AND LOCATION OF THE SAFETY EQUIPMENT.

If you are watching over someone who is in an enclosed space and you see him getting into difficulties -

• DO NOT GO IMMEDIATEL y TO THE ASSISTANCE OF THE MAN IN TROUBLE -this way there are likely to be two casualties instead of a possible one casualty.

• RAISE THE ALARM. This you may be able to do by, for instance, actuating a pump room alarm, informing the officer in charge, or informing the bridge.

• Wait for help • Do not enter the space unless you are wearing breathing apparatus. • Do not enter the space unless you have another person available to you to take your place

at the entrance to the space, and to watch over you. • THINK

DO NOT BECOME THE NEXT CASUALTY YOURSELF There is much more detailed information about safe operations available in your ship. Ask the Chief Officer. He can help you with information and advice. He will make them freely available. He will answer any of your questions. If you want to read more for yourself he can recommend books.



TYPES OF CARGOES YOU MAY CARRY

On chemical tankers you may be carrying a wide variety of different cargoes. The hazards connected with anyone cargo may be very different from those connected with any other. We will now describe some of the different types of cargoes, together with the hazards associated with them. You will not be called upon to make any decisions about these cargoes, and you will always be told by your officers about the cargoes you are handling or carrying. On each occasion you will be instructed as to the various precautions you must take while handling specific cargoes. Should you wish to learn more about the cargoes, or to get printed information about them, you can get it from the "TANKER SAFETY GUIDE (CHEMICALS)", which is always available onboard. This book is published by the INTERNATIONAL CHAMBER OF SHIPPING, and contains information about most of the chemicals your ship will carry. You should ask your officers where this publication is kept onboard, and familiarise yourself with the cargoes you are carrying or handling. The "Tanker Safety Guide (Chemicals)", Volumes II, III and IV list these cargoes under the following headings :-

• appearance • odour • the main hazards • emergency procedure in case of accidents • fire and explosion data • chemical data • reactivity information • health data • effect of liquid on various parts of the body • effect of vapour on various parts of the body • physical data

The following are the types of cargo you will carry: Corrosive cargoes Corrosive cargoes (liquids) have three special properties, which concern us -

• corrosive liquids destroy the human tissue in the body, causing serious damage that may be permanent.

• they can corrode the cargo tank construction materials, pipes, pumps etc., which are used for their safe containment

• corrosive liquids can become flammable and can produce flammable gases when in contact with some materials such as metal or fibrous materials.

METAL plus CORROSIVE LIQUID = HYDROGEN GAS FIBROUS MATERIAL plus CORROSIVE LIQUID = FIRE



Precautions for Corrosive Cargoes -

• All materials used in the construction of the tanks and cargo system must be resistant to corrosion

• While these cargoes are being handled you must, when on duty, wear full protective clothing as instructed by your officers. All parts of the body, especially the eyes, must be covered.

• Great care must be taken when opening up a tank, space, valve, line or blank. If you think corrosive liquid may be present and may splash you, protective clothing must be worn.

• Materials such as cotton waste must not be used for mopping up corrosive liquids. Corrosive liquids and waste etc., will cause fire.

• If you are splashed with corrosive liquid, remove your clothes and wash yourself with plenty of water. Showers are available on deck for this purpose.

REPORT ALL ACCIDENTS TO YOUR OFFICERS. Flammable Cargoes All liquids can change, or be changed, into VAPOUR. The process of changing a liquid into a vapour is called EVAPORATION. A vapour given off by a liquid may be called a gas. In most instances it is the Vapours or Gases given off by a liquid which burn. The liquid does not usually burn on its own. Some liquids EVAPORATE more quickly than others. Some evaporate only at high temperatures while others will evaporate at fairly low temperatures. The liquids which evaporate at low temperatures are the most dangerous. Most VAPOURS or GASES only burn it they are mixed with OXYGEN. Oxygen is present in the air around us and amounts to about 1/5th of the total percentage of air . A FLAMMABLE VAPOUR is one, which is capable of being set on fire. A FLAMMABLE MIXTURE is a mixture of vapour and air (or oxygen), which is capable of being set on fire. Most FLAMMABLE MIXTURES will only burn when there is a certain percentage of air (or oxygen) present. There may be too little air (or oxygen) for it to burn, in which case the mixture is considered to be too RICH, or there may be too much air (or oxygen) present to allow the mixture to burn, in which case the mixture is too WEAK. The mixture will only burn when it is not too weak and not too rich. In this case it is between the FLAMMABLE LIMITS, and in the FLAMMABLE RANGE. This RANGE has an upper and lower limit, called the LOWER FLAMMABLE LIMIT (or lower explosive limit) and the UPPER FLAMMABLE LIMIT (or upper explosive limit), referred to as



either LFL and UFL or LEL and UEL. The mixture will only burn when it is between the Lower Flammable Limit and the Upper Flammable Limit - i.e. between the LFL and the UFL. The flammable cargoes you carry and handle will have a FLASH POINT. This is the lowest temperature at which the liquid will give off enough vapour to form a flammable mixture. Many liquids may evaporate very easily. With these, vapour will nearly always be present. They produce plenty of gas (or vapour) at normal atmospheric pressure and temperature. A small hot spark will set it on fire –that is to say it will ignite if there is a SOURCE OF IGNITION present. A source of ignition could be, for example, a torch (or flashlight) which is not approved, and which might produce a small spark. Poisonous and Toxic Cargoes Fire is the best known danger in tankers. In Chemical Tankers, apart from the fire hazard, some cargoes may be TOXIC or POISONOUS. Toxicity is the ability of a substance to harm you if it reaches a sensitive part of your body. A substance can do even more damage to you, although both poisonous and toxic substances can KILL. Some toxic cargoes will harm you if they are INHALED. This may -

• dull your sense of smell • make you dizzy • produce a diminished sense of responsibility • give you a headache • irritate your eyes • cause staggering and confusion (appearance of drunkenness) • cause loss of consciousness • cause your breathing to stop • cause death

Inhalation of some toxic vapours may lead to :- • brain damage • damage to the nervous system • damage to the liver and other vital organs • death

As cargo enters the tank, vapour is vented to the atmosphere through the venting system. This is known as CLOSED LOADING. Some cargoes, because of unusually high toxic hazard, or objectionable odour, may require the vapour to be returned ashore. This is done through a hose connected to the gas line and called a VAPOUR RETURN CONNECTION.



If it is necessary to open the tanks (and so allow the toxic vapours to escape to atmosphere) for sampling or other purposes -

• wait for instructions from the Officer in charge. • the pressure in the tank must be released very carefully. • you must wear full protective clothing and breathing apparatus. • the tank lid must be closed again as soon as possible.

When disconnecting hoses used for handling toxic or poisonous cargoes - • wait for instructions from your officers • wear protective clothing and breathing apparatus • make sure the hose is properly drained before starting to disconnect. Before

disconnecting open the test cock to make sure the line is not under pressure. If there should be a spillage of toxic or poisonous cargo -

• get away from the area of the spill. • raise the alarm. • take your instructions from the Officer in charge of cargo operations.



More about Toxic and Poisonous Cargoes Some toxic or poisonous cargoes will harm you if they are ABSORBED into the body through the skin. This may lead to -

• Irritation of the skin • Dermatitis • Skin cancer • Blood poisoning • Damage to the vital organs • Death

When handling toxic or poisonous cargoes - • Avoid all possibility of your skin contacting the cargo. • Wear protective clothing as instructed by your officers. • Carefully follow the instructions of your officers.

If you do come into contact with a cargo of this type - • Remove all affected clothing • Wash the affected area with large quantities of water • Inform the officer of the watch • Get medical advice (your officer will arrange this}

Toxic cargoes will harm you if they are swallowed, leading to damage to many parts of the body, and possibly to death. When handling these products -

• Keep your hands away from your mouth and face • Never allow your clothing to come into contact with your mouth • Wash thoroughly before going off duty or before taking a meal

When toxic or poisonous cargoes are being loaded or discharged through a pump room system -

• The pump room ventilation must be started at least fifteen minutes before the operation begins

• Pump room ventilation must be kept running throughout the operation • Such cargoes must not be allowed to accumulate in the pump room bilges • Frequent checks must be made on the pump room atmosphere • If there are any leaks the cargo operation must be stopped immediately • Pumps should be controlled, (as far as possible) from outside the pump room • Never enter the pump room unaccompanied unless it is essential • Never enter the pump room unless you are instructed to do so by the officer in charge. In

this case follow his instructions regarding clothing and breathing apparatus.



Reactive Cargoes Some of the cargoes you carry may be REACTIVE. Cargoes may -

• be self reactive • react with air • react in contact with another cargo • react with water

Reaction may take a variety of forms, and may :-

• Produce heat • Release vapour • Produce a rise in pressure in the tank • Affect the cargo quality • Increasing danger of fire or explosion • Increase the health hazard • Polymerise (solidify)

The possibility of reaction is removed in a variety of ways -

• The addition to the cargo of an INHIBITOR to render the cargo stable and safe. Inhibitor is a general term for a compound which, when added to the cargo, has the effect of slowing down or stopping a chemical change, i.e. Polymerisation, Oxidation or Corrosion.

• The application of INERT GAS to the ullage space above the cargo in the tank. Inert gas will prevent the cargo coming into contact with the air. This is called 'applying an INERT GAS BLANKET' over the top of the cargo.

• Avoiding the use of certain metals and other materials in the cargo system, with which the cargo might react.

• By stowing cargoes which may react with one another in spaces separated by a cofferdam, pumproom, or void space, or by stowing a harmless cargo between reactive cargoes.

• By carrying water reactive cargoes in "double-skin" spaces. • By blanking off heating coils in tanks carrying water reactive cargo. • By using oil as a heating medium for water reactive cargoes.



Vegetable and Animal Oils Some cargoes which you will carry will be oils, or fats, manufactured from vegetable or animal sources. These are called Animal Oils or Vegetable Oils. These oils are generally entirely safe, but they can have a tendency to OXIDISE -that is, they will absorb oxygen from the air, and so the air remaining in a tank containing vegetable or animal oil, or coated with residual quantities of these oils, may not have enough oxygen in it to support life. This is most likely to happen when a tank has been closed for a long time after the oils or fats have been discharged. The residual oil or fat on the structures in the tank starts to decompose {rot). When it does this, it not only absorbs oxygen, but also produces various toxic and asphyxiating gases such as methane, carbon dioxide and hydrogen sulphide. These gases may also be present in pumprooms or pumproom drain tanks, where oils and fats of this nature remain. It is therefore dangerous to enter a tank which has been used for vegetable or animal oils or fats unless it is being continuously ventilated with special attention being given to the lower reaches. Before entering a tank or space containing any remains of vegetable or animal oils or fats -

• Obtain the permission of the officer on duty • Measure the oxygen content of the air and make sure that it is normal {normal air which

we breathe contains 21% oxygen). Atmospheres showing an oxygen level of less than 16.5% are unsafe

• Also ensure that none of the toxic gases are present. REMEMBER: An explosimeter {combustible gas indicator) will not indicate oxygen levels or toxicity. While you are in the tank or space -

• Carry out frequent tests to make sure that the amount of oxygen in the air is not decreasing

• Make sure that somebody remains at the tank-hatch on deck, so that he can raise the alarm in the event of you getting into difficulties.

chemco handout

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