hseq-hq-06!16!00 hydrogen sulphide in operations standard

7/25/2019 HSEQ-HQ-06!16!00 Hydrogen Sulphide in Operations Standard

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Final H2S in Operations - Standard

OMV-EP Standard

Hydrogen Sulphide (H2S) inOperations

HSEQ-HQ-06-16-00

Prepared by: Date 30thSept 2010


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Contents

1 Scope and Appl ication .....................................................................3

2 Cross-References .............................................................................3

3 Management Responsibil it ies .........................................................4

4 Defini tions .........................................................................................4

5 Procedure..........................................................................................5

5.1 Thresholds Appl icabil ity and Risk Assessment ....................................... 5

5.2

Operational Pract ices.................................................................................. 5

5.3 Personnel Training ...................................................................................... 6

5.4 Health and Other Personal Factors............................................................ 7

5.5 Monitoring, Detect ion and Alarms ............................................................. 8

5.6 Personal Protective Equipment (PPE)....................................................... 9

5.7

Offshore Operat ions.................................................................................. 10

5.8

Contingency Planning and Emergency Procedures .............................. 11

6 Record of Revisions .......................................................................14

APPENDIX A Properties and Physiological Effects of H2S............15

APPENDIX B Properties and Physiological Effects of SO2 ...........17

APPENDIX C H2S Hazardous Zones ................................................19


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1 Scope and Appl ication

This standard applies to OMV Exploration & Production GmbH, all its controlledsubsidiaries and OMV Australia Pty Limited (together OMV EP Group). Controlled meansthe ownership directly or indirectly of more than fifty percent (50%) of the shares or the rightsof voting authority in a company, partnership or legal entity. Where OMV is neither theoperator nor holds the majority shareholding, OMV will seek to have this, or similar,standards adopted for all operations.

Subject to the technical threshold of applicability (refer Section 5.1 below), this standardapplies to all facilities (offshore and onshore) that are directly operated by OMV E&P (or itssubsidiaries) and to facilities that are contracted to OMV or subject to a service operatingagreement with OMV.

Hydrogen Sulphide is highly toxic, flammable and corrosive. Engineering controls,operational and maintenance procedures are the primary methods to minimise the risks

resulting from processing well fluids containing Hydrogen Sulphide (H2S). To supplementthese controls personnel exposed to the risks must be properly trained so that they fullyunderstand the hazards, controls, mitigation, alarms and emergency response when workingwithin an H2S environment. The correct selection, provision and maintenance of personalprotective equipment are the main occupational health controls when working with H2S.

This standard is focused on occupational health and safety relevant to H2S and SulphurDioxide (SO2) which is a by-product resulting from the combustion of Hydrogen Sulphide.

This standard applies to production operations and drilling & well servicing operationsactivities. The standard is not intended to cover the engineering design, material selectionand maintenance for facilities where H2S is present.

This standard sets the minimum standards. When in-country laws, statutes, regulations orrisk assessments state different requirements then the more stringent shall apply.

2 Cross-References

API RP55, Recommended Practice for Oil and Gas Processing Plant Operations InvolvingHydrogen Sulfide, March 2007.

EP-HSEQ Standard No HSEQ-04-03 latest revision, Health Standard.

EP HSEQ Standard No HSEQ 06 01 latest revision Workplace Risk Assessment (also


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3 Management Responsibilit ies

The General Managershall be responsible for the overall implementation of this standard.

AllManagers, Supervisors andTeam Leadersare responsible for implementing thisstandard at the working level.

The Country HSEQ Managershall ensure the occupational health records system is in place

to monitor the effects on health from exposure to H2S and SO2.

4 Definitions

Accredited Training Course H2S training in accordance with ANSI or OPITO standards

Approved H2S instructor a person who has completed an accredited training course and

can demonstrate competence as a trainer.

ANSI Standard - ANSI Z390.1 - 2006: Accepted Practices for Hydrogen Sulfide SafetyTraining Programs.

Hydrogen Sulphide Colourless, toxic and flammable gas that is slightly heavier than air(vapour density is 1.189). H2S has an extremely unpleasant odour, characteristic of rotteneggs, and is easily detected at low concentrations. However, due to rapid onset of olfactoryfatigue and paralysis (inability to smell) odour shall not be used as a warning measure. Referalso to Appendix A.

Sulphur Dioxide A product of the combustion of H2S. A colourless, toxic, non-flammablegas that is much heavier than air (vapour density is 2.26). SO2has a pungent odourassociated with burning sulphur. It produces a suffocating effect and produces sulphurousacid on membranes of the nose and throat. Refer also to Appendix B.

Abbreviations

OPITO The Oil and Gas Academy Standard for Basic and Advanced H2S Training,EERA Evacuation, escape and rescue assessmentSCBA Self contained breathing apparatusSTEL Short term exposure level


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5 Procedure

5.1 Thresholds Applicability and Risk AssessmentThe threshold criteria for the implementation of this standard apply:

When the work area concentration of H2S exceeds 10 ppm during an eight-hourtime weighted average (TWA) or 15 ppm as a short term exposure level (STEL)averaged over 15 minutes

When the work area concentration of SO2exceeds 2 ppm during an eight-hour

TWA or 5 ppm as a STEL averaged over 15 minutes

All operating conditions shall be considered when evaluating the facility specific thresholdconcentrations. These conditions are: normal operations, simultaneous or concurrentoperations, start up/shutdown, emergency shutdown, maintenance, testing and inspection.

Exposure and inhalation of a short duration puff of H2S at 1000 ppm can be a fatal dose and

all process streams of the facilities should be reviewed to determine where higher thanaverage concentrations of H2S are likely to occur as part of the normal gas treatmentprocess. Emergency and process upset conditions shall also be evaluated in this review.

The risk assessment shall evaluate where there is the possibility of localised and above anaverage concentration of H2S (e.g. drain pits, offshore modules, drains caissons, adverseweather shelters or any confined space).

The likelihood of accidental releases or localised concentrations of H2S shall be fully

analysed using leak frequency data, source modelling, vapour cloud dispersion techniques toassess toxicity/dose, fire and explosion risks. The process risk assessment shall besupplemented by a H2S specific evacuation, escape and rescue assessment (EERA). Therisk assessment shall be used to define facility specific H2S hazardous zone classification(refer to Appendix C).

Inspection, maintenance, testing and modifications activities on facilities that process H2Sshall have a formal Workplace Risk Assessment1(or Job Safety Analysis JSA) before the

work is authorised.

5.2 Operational PracticesFacilities that may exceed the threshold criteria for H2S as defined in Section 5.1 shall applythe following operational practices:

Warning signs in English and in-country language(s) shall be displayed at all


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facilities. Upon exit of the facilities the records shall be updated (refer to Section5.4).

Respiratory equipment shall be stored in hygienic conditions and regularlymaintained to manufacturers specifications. Inspection and testing shall be done inaccordance with manufacturers specifications or local regulations, whichever is themore stringent.

Strict entry/exit control shall be in place for all personnel and visitors to thefacilities. The controls shall ensure that specialist H2S training has been verifiedand that visitors are under special supervision (refer to Section 5.3 and AppendixC H2S hazardous zone classification)

Manual sampling shall use the buddy system with emergency rescue teamsequipped with self contained breathing apparatus (SCBA) on immediate standby

Rescue teams equipped with SCBA shall carry out emergency drills at a frequencyinterval not exceeding two weeks.

A trained SCBA rescue team shall be available at site when personnel are in thefacilities.

5.3 Personnel TrainingOnsite Personnel

Personnel assigned to work in areas where the possibility of atmospheric H2S concentrationsgreater than 10 ppm or atmospheric concentrations for SO2of greater than 2 ppm shall be

trained by an approved H2S safety instructor and follow an accredited training program(training type refer ANSI Z390.1 2006). The training shall cover as a minimum:

a. Characteristics and properties of H2S and SO2

b. Sources of H2S and SO2on the facilities

c. Proper use of H2S and SO2detection methods used at the work place

d. Recognition of and proper response to the warning signals for H2S and SO2detection

systemse. Symptoms of H2S and SO2exposure

f. Rescue techniques and first-aid to victims of H2S and SO2exposure

g. Proper use and maintenance of self-contained breathing apparatus for working in aH2S and SO2atmosphere (theory and hands-on practice with demonstrated

t )


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Supervisory Personnel shall have additional training in the following:a. Supervisors responsibilities of the emergency response plan

b. Effects of H2S on the technical integrity of the facilities, i.e. corrosion, hydrogenembrittlement (sulphide stress cracking) and spontaneous combustion of IronSulphide.

All personnel designated to have the above training shall have refresher training at afrequency interval not exceeding 24 months, with validation of competency.

Visitors

Prior to entering a potentially hazardous area visitors shall be briefed on H2S alarms, escaperoutes, location of emergency assembly/muster areas and how to respond in an emergencyincluding the use of personal protective equipment. The briefing shall be given by anapproved H2S safety instructor and be site-specific. Visitors shall only be allowed in thepotentially hazardous area whilst accompanied by trained personnel. In the event of an

emergency the visitor shall be immediately evacuated.

5.4 Health and Other Personal FactorsPersonnel with physiological or psychological conditions which impair normal respirationshall not be assigned to jobs involving potential exposure to a H2S or SO2environment if theuse of breathing equipment will complicate their respiratory problems.

All persons working in facilities with the potential to exceed the threshold limit in Section 5.1shall have their occupational health monitored and recorded2with reference to H2Sexposure.

H2S is an irritant to eyes. Contact lenses shall not be worn when working in a potential H2Senvironment. In particular, soft gas permeable lenses can absorb H2S and provide a muchhigher risk.

The side arms of spectacles and excessive facial hair can reduce the effectiveness of theseals for breathing apparatus. This standard only permits positive pressure breathing

apparatus and the reduction in effectiveness will primarily be from leakage of supplied air tothe outside of any facemask. Requirements for personnel working in potentially hazardousareas are as follows:

Facial hair which would interfere with the face piece seal is prohibited. It ispreferred for persons to be clean shaved with no facial hair


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5.5 Monitoring, Detection and AlarmsFor evaluation and selection of continuous H2S monitoring equipment for use in operations,refer to API RP 55.

Fixed H2S Monitoring Systems

Fixed H2S monitoring systems shall be used in all facilities that exceed the threshold limits inSection 5.1. They shall include visual and audible alarms that can be seen and heardthrough out the work area. Fixed systems should also be used to monitor clean air intakes for

enclosed areas when the air is used for make-up, ventilation or pressurising the enclosedfacilities.

Portable H2S Detection Equipment

Portable H2S detection instruments shall be available to supplement the fixed H2S monitoringsystems. These may be required as the result of workplace risk assessment or if there arespecial tasks, such as vessel entry, or other temporary activities that require additional riskcontrols.

Where SO2levels can exceed that stipulated in Section 5.1 then portable SO2detectors shallbe used. In particular when hydrocarbons containing H2S are being flared these detectorsshall be located taking into account vulnerable populations and meteorological factors.

Where colorimetric indicator tubes are used for portable detectors, personnel shall besupplied with an adequate supply of detector tubes.

Personal H2S Monitoring

Personal H2S monitors shall have the following features:

Real time concentration

Peak concentration

Time weighted average (TWA)

Short term exposure level (STEL)

Visual and audible alarms for low, high, TWA and STEL health risk events

Battery low warning alarm

Weather proof to IP67

Data recorder with facility to download information to a secure/confidential


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Alarm Set PointsHydrogen Sulphide

Low level: 10 ppm

High level: 15 ppm

Sulphur Dioxide

Low level: 2 ppm

High level: 5 ppm

Note the above alarm levels are maximum settings. Where local regulations, facility specificconditions or risk assessment specify lower levels, then the lower levels shall apply.

Drilling, Workover and Well ServicingMonitoring equipment (fixed and portable) shall be used during all drilling, workover and well

servicing operations wherever there is a possibility of H2S or SO2exceeding the thresholdcriteria in Section 5.1 above.

Sensors should be located at the following locations:

i. Bell nipple

ii. Mud return line receiver tank (possum belly), and/or shale shaker

iii. Pipe-trip tank

iv. Driller/Operator stationv. Living quarters if located in close proximity to the well as determined by site specific

consequence modelling

vi. All other areas where H2S may accumulate that are not part of the confined spaceentry program

5.6 Personal Protective Equipment (PPE)

For additional guidance on PPE, refer to API RP 55.

Breathing (Respiratory Protection) Equipment

The risk assessment and emergency response plans referred to in Section 5.1 shall be usedto determine the quantity and location of breathing equipment available.


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Positivepressure/pressure-demand, air-line breathing equipment, with an auxiliaryself-contained air supply (rated for a minimum of 5 minutes). This type can be usedfor entry as long as the air line is connected to a source of breathing air. Theauxiliary self-contained air supply when rated for less than 15 minutes is suitableonly for emergency escape.

Low pressure warning alarms shall be set for 5-minutes remaining air as minimum. This limitshall be increased if the risk assessment and EERA (Ref Section 5.1) require a longer time.

Hood type self-contained positive-pressure breathing apparatus may be used only foremergency escape. These should have a minimum of 5 minutes air capacity. This limit shallbe increased if the risk assessment and EERA (Ref Section 5.1) require a longer time.

NOTE Gas mask canister type breathing and demand type (negative-pressure) equipmentshall not be used.

Air Supply

Breathing air quality shall meet the following requirements:

1. Oxygen content 19.5% to 23.5%

2. Hydrocarbon (condensed) content of 5 mg/m3 (or less) per cubic metre of air

3. Carbon Monoxide content of 10 ppm or less

4. Carbon Dioxide content of 1,000 ppm or less

5. Lack a noticeable odour

Eye and Skin Protection

Personal protective equipment shall be worn where appropriate to prevent eye and skincontact with liquids containing H2S and eye irritation from exposure to airborneconcentrations of H2S, as follows:

Gloves Gloves made of nitrile rubber or neoprene, or other suitable materialsapproved to be used for protection of the hands against absorption of

hydrocarbons Goggles Non-vented goggles should be worn if the concentration of H 2S is not

sufficient to warrant the use of a respirator but the potential for eye irritation exists.

Protective Clothing Where atmospheres with high concentrations of H2S exist,chemical protective clothing shall be used to prevent irritation to damp exposedskin


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upwind of any potential toxic or flammable vapour clouds. Suitable emergency breathingequipment shall also be provided for rescue teams in vessels or helicopters.

5.8 Contingency Planning and Emergency ProceduresAll operations are required to comply with EP-HSEQ Standard No HSEQ-HQ-10-01 latestrevision, Standard for Management of Emergencies, (refer Section 2 above). Site specificcontingency plans and emergency procedures shall be implemented for scenarios ofaccidental and uncontrolled releases of Hydrogen Sulphide or Sulphur Dioxide. The plansand procedures shall cover personnel working on the facility and also all persons at risk whoare external to the facility boundary.

The contingency plan shall contain emergency response procedures that provide anorganised immediate action plan for alerting and protecting operating personnel, contractorpersonnel and the public. Contingency plans shall consider the severity and extent of theanticipated atmospheric hydrogen sulphide and sulphur dioxide concentration together withdispersion characteristics that are based on recognised analytical consequence models.


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Plan InformationTypically the contingency plan should contain, but not be limited to:

Emergency Procedures

Responsibilities of personnel

Immediate action plan

Notification list and communication methods

For onshore maps showing locations of nearby residences, business,schools, hospitals, vulnerable populations. To include transient or nomadicpopulations.

For offshore adjacent or bridge/pontoon linked facilities. To include ships,barges, MODUs that may be temporarily located near the source ofreleases.

For onshore evacuation routes and road block locations

For offshore temporary refuges, escape, evacuation and rescueequipment. Modes of transportation. To include shared emergencyresponse facilities, e.g. helicopters, military/coastguard support, supplyvessel, emergency standby vessels, etc. Adverse weather limitations andcontingency arrangements.

Safety equipment including special breathing apparatus

Characteristics of Hydrogen Sulphide and Sulphur Dioxide

Refer Appendices A & B of this standard. Provide specific information ofconcentrations in high risk areas and process units during normaloperations.

Facility Descriptions, Maps and Drawings

Water injection stations

Wells tank, batteries, gas conditioning facilities and flowlines.

Compression facilities


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Onsite or desktop drills

Informing nearby residents on protective measures in emergency situations

Training and attendance documentation

Briefing of public officials, media representatives and other concernedparties.

Feedback and continuous improvement from drills and actual emergencyevents

Immediate Action PlanThe contingency plan shall contain an Immediate Action Plan that has concise instructionsabout what to do when a potentially hazardous release of hydrogen Sulphide or Sulphurdioxide occurs.

This should include but not be limited to the following provisions:

Alert and Account for Facility Personnel

Move upwind of the source of release

Don/wear protective breathing equipment

Raise H2Salarm/Alert others in the affected area

Assist personnel in distress

Proceed to a designated safe muster point

Account for onsite personnel

Control and Mitigate

Initiate process control emergency shutdown (ESD) actions

Ensure process interactions with adjoining or linked facilities (e.g. offshoreoperations) are controlled and the appropriate ESD actions are initiated toprevent escalation


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Community Warning and Protection PlanFor onshore facilities a community warning and protection plan shall be developed. This shallbe based on quantitative assessment of release frequencies and toxic gas dispersion modelsthat identify the hazardous radii.

The community warning and protection plan shall contain but not be limited to:

Community Warning and Evacuation Plan

Procedures for the notification and evacuation of residents and vulnerablepopulations in the vicinity of the source release

Supporting diagrams, maps and telephone numbers for notification andevacuation arrangements of the community

Procedures for the integration of local authorities and emergency serviceswith operator services to help control and mitigate the effects of the

emergency

The emergency notification, communications and control protocol that willbe followed to ensure that the community protection measures will beimplemented.

Description and location of all safety and life saving appliances that areavailable to the operating personnel and local authorities to support thecommunity warning and protection plan.

Well Ignition PlanWhen drilling and well servicing operations are being carried out a plan shall be prepared forignition of an uncontrolled release from a well. The plan should clearly state under whatconditions well ignition is to take place and who is the designated on-site person (or deputy)with the authority to ignite the well. The decision to ignite the well should be made only as alast resort and only in a situation where it is clear that:

Human life is endangered

There is no hope of controlling the well under the prevailing conditions.

The combustion of hydrogen sulphide will produce sulphur dioxide (which is much heavierthan air). The well ignition plan shall also cover how the ground level concentration of sulphur


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Exploration & Production, HSEQ, ViennaDocument No HSEQ-HQ-06-16-00

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APPENDIX A Properties and Physiological Effects of H2S

Physical data

Chemical name Hydrogen Sulphide

Synonyms Sulphureted hydrogen, hydrosulphuric acid, dihydrogen sulphide

Chemical family Inorganic sulphide

Chemical Formula H2S

Normal Physical State Colourless gas, slightly heavier than air. Vapour density (specific gravity) at 15 degC and 1atmosphere = 1.189

Auto Ignition Temperature 260 degC

Boiling Point -60.2 degC

Melting Point -82.9 degC

Flammable Limits 4.3 to 46 percent vapour by volume in air

Solubility Soluble in water and oil; solubility decreases as the fluid temperature increases

Combustibility Burns with blue flame to produce sulphur dioxide

Odour and Warning Properties Hydrogen sulphide has an extremely unpleasant odour, characteristic of rotten eggs, and is easilydetected at low concentrations. However, due to rapid onset of olfactory fatigue and paralysis(inability to smell) odour shall no t be used as a warning measure.


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Physiological Effects

Data Source: API RP 55, March 2007

Concentration in Air

Percent byVolume

Parts permillion by

volume

Milligramsper cubic

meter

Typical Characteristics Regarding Hydrogen Sulphide (H2S) Exposure

0.000013 0.13 0.18 Obvious and unpleasant odour generally at 0.13 ppm and quite noticeable at 4.6 ppm. As theconcentration increases, the sense of smell fatigues and the gas can no longer be detected.

0.001 10 14.41 Unpleasant odour. Possible eye irritation. Threshold limit for 8 hour time weighted average (TWA).

0.0015 15 21.61 Threshold short term exposure limit (STEL) averaged over 15 minutes.

0.002 20 28.83 Burning sensation in eyes and irritation of the respiratory tract after one hour or more exposure.

0.005 50 72.07 Loss of sense of smell after about 15 minutes exposure. Exposure over one hour may lead toheadache, dizziness and/or staggering. Pulmonary oedema reported following extended exposure togreater than 50 ppm. Exposure at 50 ppm or greater can cause serious eye irritation or damage.

0.01 100 144.14 Coughing, eye irritation, loss of sense of smell after 3 to 15 minutes. Altered respiration, pain in eyes,and drowsiness after 15 to 20 minutes, followed by throat irritation after one hour. Prolongedexposure results in gradual increase in the severity of these symptoms.

0.03 300 432.40 Marked conjunctivitis and respiratory tract irritation. Concentration considered immediatelydangerous to life or health (IDLH)

0.05 500 720.49 Unconsciousness after short exposure, cessation of breathing, if not treated quickly. Dizziness, lossof sense of reasoning and balance. Victims need prompt artificial ventilation and/or cardiopulmonary

resuscitation techniques.0.07 700 1008.55 Unconscious quickly. Breathing will stop and death will result if not rescued promptly. Artificial

ventilation and/or cardio resuscitation is needed immediately.

0.10+ 1000+ 1440.98+ Unconscious at once. Permanent brain damage or death may result. Rescue promptly and applyartificial ventilation and/or cardio pulmonary resuscitation.


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APPENDIX B Properties and Physiological Ef fects of SO2

Physical data

Chemical name Sulphur Dioxide

Synonyms Sulphureted hydrogen, sulphurous oxide

Chemical family Inorganic

Chemical Formula SO2

Normal Physical State Colourless gas, appreciably heavier than air. Vapour density (specific gravity) at 0 degC and 1atmosphere = 2.26

Boiling Point -10 degC

Melting Point -82.9 degC

Flammable Limits Non-flammable (produced from burning hydrogen sulphide)

Solubility Readily soluble in water and oil; solubility decreases as the fluid temperature increases

Odour and Warning Properties Sulphur dioxide has a pungent odour associated with burning sulphur. It produces a suffocating effectand produces sulphurous acid on membranes of the nose and throat.


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Physiological Effects

Data Source: API RP 55, March 2007

Concentration in Air

Percent byVolume (%)

Parts permillion by

volume (ppm)

Milligramsper cubic

meter (mg/m3)Typical Characterist ics Regarding Sulphur Dioxide (SO2) Exposure

0.0001 1 2.71 Pungent odour, may cause respiratory changes.

0.0002 2 5.42 Threshold limit for 8 hour time weighted average (TWA).

0.0005 5 13.50 Burning eyes, breathing irritation and minor throat irritation.

0.0012 12 32.49 Throat irritating cough, constriction in chest, watering eyes and nausea.

0.010 100 271.00 Concentration considered immediately dangerous to life or health (IDLH).

0.015 150 406.35 Extreme irritation. Can be tolerated for only a few minutes.

0.05 500 1354.50 Causes a sense of suffocation, even with the first breath. Rescue promptly and apply artificialventilation and/or cardio pulmonary resuscitation.

0.10 1000 2708.99 Death may result unless rescued promptly. Artificial ventilation and/or cardio pulmonary resuscitationtechniques should be immediately applied.


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APPENDIX C H2S Hazardous Zones

H2S ExceedsThreshold inSect 5.1 for

Facility

PermanentMonitor

PortableMonitor

PersonalAlarm &Monitor

Fixed Air-LineRespiratoryProtection

(RP)

Emergency EscapeRespiratory Protection

Test forH2S levels

beforeentry

On-SitePersonnel

Trained(Sect. 5.3)

Al low Vis itors Note #4

Zone 0

H2Salwayspresent inatmosphere

Yes See #1below

No Yes - to beused at all

times

Yes Note #2 No Yes Only if trained(Sect 5.3) +

accompaniedwith regularon-site person

Zone 1

H2S may occurin atmosphere

Yes See #1below

Yes Option to useSCBA RP

Yes Note #2 Yes Yes H2S and ERsite induction +accompaniedwith regularon-site person

Zone 2

H2S not inatmosphereduring normaloperations

Yes See #1below

Yes Optional canuse temporaryor SCBA RP,as required by#1 below

Yes, when H2S in processstreams > 500 ppm

Subject to risk assessmentwhen H2S in processstreams < 500 ppm (Note#3)

Yes Yes H2S and ERsite induction +accompaniedwith regularon-site person

Notes1. Applies when invasive/internal inspection, maintenance or testing is being carried out. Also applies during modifications, construction, drilling

or well servicing activities.2. To be carried by individuals at all times when on the facilities.3. Effects on humans of H2S for short durations at concentrations < 500 ppm are considered reversible.4. Subject to site medical officer review (refer Section 5.4 for guidance). ER: emergency response.

hseq-hq-06!16!00 hydrogen sulphide in operations standard

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