offshore fixed rig risk
DESCRIPTION
Offshore RiskTRANSCRIPT
HSE Health & Safety
Executive
Accident statistics for fixed offshore units on the UK Continental Shelf
1980 - 2001
Prepared by Det Norske Veritas Industry AS
for the Health and Safety Executive 2003
RESEARCH REPORT 096
HSE Health & Safety
Executive
Accident statistics for fixed offshore units on the UK Continental Shelf
1980 - 2001
Espen Funnemark Det Norske Veritas Industry AS
Safety & Process Advisory Services Veritasveien 1
1322 Hovik Norway
Eoin Young HSE Offshore Division
Room G SW Rose Court
London SE1 9HS
This project updates previous project; Accident Statistics for Fixed Offshore Units on the UK Continental Shelf, 1991 - 1999. The Health and Safety Executive (HSE) published the project as OTO 2002/012. This project follows the same format for fixed offshore units and extends the data coverage to 21 years, 1980 - 2001.
The work was commisioned by the HSE as it had been noted that event frequencies quoted in the safety cases of offshore installations tended to be lower than experience would anticipate.
It has been noted that extensive use has been made of OTO 2000/012 in safety cases submitted following publication. Typically a review of relevant incidents has assisted the duty holder in confirming that he has in place adequate mitigating measures.
This report and the work it describes were funded by the HSE. Its contents, including any opinions and/or conclusions expressed, are those of the authors alone and do not necessarily reflect HSE policy.
HSE BOOKS
© Crown copyright 2003
First published 2003
ISBN 0 7176 2211 8
All rights reserved. No part of this publication may bereproduced, stored in a retrieval system, or transmitted inany form or by any means (electronic, mechanical,photocopying, recording or otherwise) without the priorwritten permission of the copyright owner.
Applications for reproduction should be made in writing to:Licensing Division, Her Majesty's Stationery Office, St Clements House, 2-16 Colegate, Norwich NR3 1BQ or by e-mail to [email protected]
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Table of Contents
1
1.1
1.2
1.3
2
3
4
5
5.1 5.1.1 5.1.2 5.1.3
5.2
5.3 5.3.1 5.3.2 5.3.3 5.3.4 5.3.5 5.3.6 5.3.7 5.3.8
6
6.1
6.2 6.2.1 6.2.2 6.2.3 6.2.4 6.2.5 6.2.6 6.2.7 6.2.8
7
8
8.1
8.2 8.2.1 8.2.2
Page
EXECUTIVE SUMMARY ......................................................................................... 1
Introduction and background 1
Confidentiality 1
Objectives, results and conclusions 2
INTRODUCTION ....................................................................................................... 7
OBJECTIVES AND SCOPE OF WORK.................................................................... 9
EXPOSURE DATA................................................................................................... 11
ORION DATABASE................................................................................................. 13
Available data 13 Incident category codes 14 Dangerous occurrence type codes 14 Broad incident type codes 15
Event classification and coding principles 16
Result of interrogation All fixed units Drilling units Production units Wellhead units Compression units Pumping units Injection/riser units Accommodation units
18 25 29 30 34 38 42 42 43
WOAD ....................................................................................................................... 45
Available data
Result of interrogation All fixed units Drilling units Production units Wellhead units Compression units Pumping units Injection/riser units Accommodation units
45
46 52 55 56 60 60 61 61 61
BLOWOUT DATABASE ......................................................................................... 63
ACCIDENT STATISTICS ........................................................................................ 65
Accident frequencies, All databases combined 65
Occurrence frequencies, ORION&WOAD 67 All fixed units 69 Drilling units 72
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8.2.3 Production units 73 8.2.4 Wellhead units 77 8.2.5 Compression units 81 8.2.6 Pumping units 84 8.2.7 Injection/riser units 84 8.2.8 Accommodation units 84
8.3 Frequencies, fixed units on NCS 86
9 CONCLUSIONS........................................................................................................ 87
10 REFERENCES .......................................................................................................... 89
Appendix A HSE ORION; DANGEROUS OCCURRENCE TYPE CODES
This report is part 1 of the published data. Part 2 is the associated spreadsheet listing
individually the coding and text for each incident.
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1 EXECUTIVE SUMMARY
1.1 Introduction and background In 1999, a project was initiated for the purpose of obtaining accident statistics for offshore floating units on the UK Continental Shelf (UKCS). In this respect, five databases holding information about incidents having occurred on floating units on the UKCS were interrogated. The survey revealed that that none of them had a complete recording of such incidents. Consequently, the event frequencies being obtained varied with the availability of sources. There was no reason to believe that the situation and figures for fixed installations should be any different. Hence, it was proposed to initiate a similar type of project, but addressing all types of risks to fixed units. It should be noted that fixed units in this project are defined as comprising all bottom-fixed structures, but excluding TLPs, FPSOs, FSUs and production jackups even though they are “fixed” during their production phase. Accident statistics for the excluded units are found in HSE’s OTO Report No. 2000/091 “Accident Statistics for Floating Offshore Units on the UK Continental Shelf in 1980-98”.
Initially, the proposed project for fixed units was to address the whole period 1980-2001, but since it was realised that accidents from the period 1980-90 held by the former Sun Safety System had not been transferred to the ORION database, the project was therefore limited to cover 1991-99. The results from this study are found in HSE’s Offshore Technology Report – OTO 2002/012 “Accident Statistics for Fixed Offshore Units on the UK Continental Shelf in 1991-99”. In August 2001, HSE reported that the missing data was successfully retrieved and available at the same format as 1991-99 data. It was then decided to set out a new project with the objective of analysing the 1980-90 accident data and to obtain relevant exposure data in line with what was done for the recent period 1991-99. The project deliverable should be an update/revision of the existing report for the period 1991-99.
Prior to 1991 the regulation of offshore safety was the role of the Department of Energy, DEn. During the period that the DEn was in place, data concerning incidents and accidents on offshore installations within the UKCS was passed to the WOAD databank. From 1991 the role of regulation of offshore safety passed to the HSE and very little, if any, data was passed to WOAD. The Health And Safety At Work Act, HASAWA, Section 28, Disclosure of Information, being interpreted at the time by the HSE so as to prevent the transfer of such information. As a consequence, from 1991 until very recently no UKCS offshore installation incident data has been made available to WOAD by the HSE. Therefore current WOAD risk estimates exclude incidents and accidents on the UKCS except for those where adequate quality information has been made available in the public domain.
A recent HSE legislative review of Section 28 allows, conditionally, the transfer of such data from the HSE to WOAD. Provided that the project is in line with the general function of the HSE "To secure the health, safety and welfare of persons at work" then it will not be in contravention of HASAWA. This project has been accepted by the Open Government Unit of the HSE as fulfilling that condition and in addition confidentiality is protected in that the information so transferred has been "ring fenced".
1.2 Confidentiality In order to ensure that the final results of the project were accurate and in line with the Quality Control requirements of the WOAD databank it was necessary to obtain "raw" data from each of the Databases interrogated. Raw data being defined as the data concerning a specific incident which identified the installation, operator, location, date and time. The data so obtained enabled quality
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checks to be undertaken on the different databases to prevent double counting of an incident or accident.
It is a condition of the contract between the HSE and DNV, the custodians of the WOAD databank, that any information so obtained will only be exported in a non attributable form to protect confidentiality and once the project is completed, the raw data will be destroyed. That is, any request for data obtained by WOAD as a result of this project will result in data being supplied which is non attributable and will not allow identification of the name of the installation, company, location, date or time of an incident. It will thus be impossible to pinpoint the installation or operator by any means.
1.3 Objectives, results and conclusions The main objective of the project is to obtain complete statistics (i.e. accident frequencies) for accidents and incidents having occurred on fixed units engaged in the oil and gas exploration and exploitation on the UKCS in the period 1980-2001. This is published both as a written report and an associated spreadsheet in the MS Excel format listing individually the coding and text for each incident.
Fixed units in this project are defined as comprising all bottom-fixed structures, but excluding TLPs, FPSOs, FSUs and production jackups even though they are “fixed” during their production phase. Accident statistics for the excluded units are found in HSE’s OTO Report No. 2000/091 “Accident Statistics for Floating Offshore Units on the UK Continental Shelf in 1980-98”.
The results from this study would serve as a reference document for data to be used in future Risk Assessments of offshore Fixed units and furthermore, be a valuable reference document for UK Health & Safety Executive (HSE)/ Offshore Safety Division (OSD) when reviewing Safety Cases.
To fulfil this objective, relevant databases were interrogated with respect to both population and accident data. This forms a complete basis of data for obtaining comprehensive accident statistics for the type of units, geographical area and time period considered in this project. The following databases were selected for interrogation:
• ORION (the former Sun Safety System); UK HSE-Offshore Safety Division • Offshore Blowout Database (SINTEF, Norway) • Worldwide Offshore Accident Databank WOAD (Det Norske Veritas (DNV), Norway)
By combining and merging the results from the interrogation of the ORION and WOAD databases, the accident frequencies for fixed units in the UKCS in the period 1980-2001 are estimated. Note that the Offshore Blowout Database did not hold information about accidents on UKCS in the given period beyond what was already recorded in the WOAD and ORION databases. In the following tables the accident frequencies (i.e. number of accidents per unit year) are given per type of installation, period and data source. N denotes number of accidents and F denotes frequency, i.e. number of accidents per unit and year. The source ORION&WOAD refers to the database obtained by pooling the ORION and WOAD databases and removing the overlapping records.
The result after having interrogated the databases and removing overlapping records is shown in an Excel spreadsheet, which may be downloaded from HSE’s Internet Home Page www.hse.gov.uk , documenting a total of 5563 events comprising accidents, hazardous situations and near-misses. Note: Best efforts have been made to ensure complete anonymity within the free text associated with each incident. However, it is possible that within the 5563 incidents some anonymisation has been missed.
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Table 1 Fixed Units (I). UKCS, 1980-2001. No. of accidents and accident frequencies (per unit year). Source: ORION&WOAD
Type of installation
Drilling Production Wellhead Compression
Year/period N F N F N F N F
1980-89 19 0.1152 995 1.6311 13 0.0861 8 0.1159
1990 8 0.4444 173 2.2763 9 0.2308 1 0.125
1991 3 0.1667 199 2.5190 7 0.1556 2 0.2222
1992 320 3.9506 9 0.1875 6 0.6667
1993 1 0.0526 407 4.7326 17 0.3333 3 0.3000
1994 9 0.4737 474 5.1522 9 0.1607 5 0.5000
1995 350 3.8043 21 0.3684 13 1.1818
1996 1 0.0588 359 3.8602 22 0.3385 8 0.8889
1997 3 0.1667 368 3.9149 37 0.5286 4 0.3636
1998 1 0.0556 365 3.7629 36 0.5000 2 0.1818
1999 1 0.0556 319 3.3229 41 0.5190 5 0.4167
2000 410 4.1837 40 0.4762 2 0.1667
2001 411 4.1515 24 0.2824
1990-99 27 0.1406 3334 3.7630 208 0.3574 49 0.4900
1980-2001 46 0.1201 5150 3.0419 285 0.3160 59 0.3057
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Table 2 Fixed Units (II). UKCS, 1980-2001. No. of accidents and accident frequencies (per unit year). Source: ORION&WOAD
Type of installation
Pumping Injection/riser Accommodation All fixed, (I) & (II)
Year/period N F N F N F N F
1980-89 1 0.0222 7 0.1707 1043 0.9473
1990 1 0.2000 192 1.2468
1991 2 0.3333 213 1.2909
1992 2 0.3333 1 0.1667 338 1.9766
1993 1 0.1250 1 0.1429 430 2.3370
1994 2 0.2500 499 2.5330
1995 384 1.9296
1996 1 0.1111 391 1.9073
1997 1 0.1000 413 1.9299
1998 1 0.1000 405 1.8409
1999 1 0.0909 367 1.6096
2000 1 0.0909 453 1.9277
2001 435 1.8354
1990-99 6 0.0750 8 0.0920 3632 1.8751
1980-2001 7 0.0483 16 0.1067 5563 1.5849
The main conclusions from the work undertaken in this project are summarised below.
• The main source for accident and incident information being available for the UKCS offshore industry should be the HSE’s ORION
Due to the accident reporting requirements for Fixed units on the UK Continental Shelf (UKCS), the main source for accident and incident information being available for the UKCS offshore industry should be the HSE’s ORION. The interrogation of ORION in this project showed that the database contains information for accidents and incidents ranging from hazardous situations and working accidents with no consequences to severe damage and total loss of units.
• Large difference in number of accidents between WOAD and ORION
When comparing the information held by DNV’s Worldwide Offshore Accident Databank (WOAD) and ORION, there is a big difference in number of accidents. This is mainly explained by the fact that WOAD only receives information about accidents through publicly available sources, which in most cases only addresses events with large consequences.
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• Slight increase in event frequencies when merging the databases together
If all fixed units are considered for the period 1980-2001, this study demonstrates a total event frequency of 1.58 per installation per year. Only a slight increase in the frequency is seen when merging the ORION and WOAD databases together. This is due to that there are only a few (51 to be exact) events being recorded in WOAD and not in ORION. The total event frequency is a factor about 35 times higher than that which is obtained from WOAD.
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2 INTRODUCTION In 1999, a project was initiated for the purpose of obtaining accident statistics for offshore floating units on the UK Continental Shelf (UKCS). In this respect, five databases holding information about incidents having occurred on floating units on the UKCS were interrogated. These were UK Health & Safety (HSE) - Field Operations Division’s (HSE-FOD) “FOCUS” database, HSE-OSD’s “Sun Safety System” database (from 2000: ORION), Marine Accidents Investigation Bureau’s (MAIB) accident database, SINTEF’s Offshore Blowout Database and Det Norske Veritas’ (DNV) “Worldwide Offshore Accident Databank”, WOAD. The survey revealed that that none of them had a complete recording of such incidents. Consequently, the event frequencies being obtained varied with the availability of sources. See ref. /1/, OTO Report No. 2000/091 “Accident Statistics for Floating Offshore Units on the UK Continental Shelf in 1980-98” for details.
There is no reason to believe that the situation and figures for incidents on fixed units are any different compared to the one addressed in the previous project. In 2001, it was therefore proposed to initiate a similar type of project, but addressing all incidents on fixed units. The results from the study are documented in ref. /2/, OTO Report No. 2002/012 “Accident Statistics for Fixed Offshore Units on the UK Continental Shelf in 1991-99”.
Initially, the latter project was to address the whole period 1980-2001, but since it was realised that accidents from the period 1980-90 held by the former Sun Safety System had not been transferred to the ORION database, the project was therefore limited to cover 1991-99. In August 2001 HSE reported that the missing data was successfully retrieved and available at the same format as 199199 data. It was then decided to set out a new project with the objective of analysing the 1980-90 accident data and to obtain relevant exposure data in line with what was done for the recent period 1991-99. The project deliverable should be an update/revision of the existing report, ref. /2/.
This report documents the results from the two latter projects, covering the period 1980-2001.
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8
3 OBJECTIVES AND SCOPE OF WORK The main objective of the project is to obtain complete statistics (i.e. accident frequencies) for accidents and incidents having occurred on fixed units engaged in the oil and gas exploration and exploitation activities on the UK Continental Shelf in the period 1980-2001. This is published both as a written report and an associated spreadsheet in the MS Excel format listing individually the coding and text for each incident. As explained above the statistics had to be produced in two separate projects due to lack of ORION data for the period 1980-90, the former covering the years 1991-99 and the latter 1980-90.
Fixed units in this project are defined as comprising bottom-fixed installations (manned or unmanned) designed for drilling, accommodation, production, compression, pumping, and injection/riser purposes, or combinations of these. Regarding production installations, the study differentiates between the traditional (manned) production platforms, steel jackets or GBSs, and wellhead platforms (normally unmanned).
It should be noted that TLPs, FPSOs, FSUs and production semi-submersibles and jackups have not been included in this study, even though they are fixed during their production phase. Accident statistics for the excluded units are found in ref. /1/, OTO Report No. 2000/091 “Accident Statistics for Floating Offshore Units on the UK Continental Shelf in 1980-98”.
The classification of units is according to the following:
Category Type of unit – description
Drilling Drilling platforms whose sole purpose is to drill
Production Traditional (manned) production platforms, steel jackets or GBSs. Included are also platforms with drilling, production, and accommodation facilities (i.e. large integrated platforms)
Wellhead Wellhead platforms (normally unmanned) with no processing facilities, serving as “well support”. Often linked to the main production platforms.
Compression Gas compression platforms
Pumping Pumping platforms
Injection/riser Water or gas injection and riser platforms
Accommodation Accommodation platforms
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The results from this study would serve as a reference document for data to be used in future Risk Assessments of offshore Fixed units and furthermore, be a valuable reference document for HSE/OSD when reviewing Safety Cases.
To fulfil this objective, relevant databases were interrogated with respect to both population and accident data. This forms a complete data basis for obtaining comprehensive accident statistics for the said type of units, geographical area and time period. The following databases were selected for interrogation:
• ORION* (UK HSE-Offshore Safety Division) • Offshore Blowout Database (SINTEF, Norway) • Worldwide Offshore Accident Databank WOAD (DNV, Norway)
*): The former “Sun Safety System”
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4 EXPOSURE DATA Exposure (population) data in this context relates to the number of unit- (or platform-) years for each type of installation. By interrogating relevant sources holding such information, the number of unit-years are obtained for each year and type of unit for the UKCS in the period 1980-2001.
From WOAD and OPL (“The North Sea Development Guide”. Seventh Edition, Oilfield Publications Limited. ISBN 1 902157 08 7, November 1998, ref. /3/), the exposure data for fixed units on the UKCS are obtained. The data are given in two following tables.
Table 3 Fixed Units (I). UKCS, 1980-2001. Number of unit-years
Type of Installation
Year Drilling Production Wellhead Compression
1980-89 165 610 151 69
1990 18 76 39 8
1991 18 79 45 9
1992 18 81 48 9
1993 19 86 51 10
1994 19 92 56 10
1995 19 92 57 11
1996 17 93 65 9
1997 18 94 70 11
1998 18 97 72 11
1999 18 96 79 12
2000 18 98 84 12
2001 18 99 85 12
1990-99 182 886 582 100
1980-2001 383 1693 902 193
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Table 4 Fixed Units (II). UKCS. 1980-2001. Number of unit-years
Type of Installation
Year Pumping Injection/riser Accommodation All fixed, (I) & (II)
1980-89 20 45 41 1101
1990 2 5 6 154
1991 2 6 6 165
1992 2 6 7 171
1993 2 8 8 184
1994 2 9 9 197
1995 2 9 9 199
1996 2 9 10 205
1997 2 9 10 214
1998 2 9 11 220
1999 2 10 11 228
2000 2 10 11 235
2001 2 10 11 237
1990-99 20 80 87 1937
1980-2001 44 145 150 3510
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5 ORION DATABASE The Reporting of Injuries, Diseases and Dangerous Occurrences Regulations 1995 (RIDDOR 95) arrangement came into force on 1 April 1996 and requires that all work-related accidents, diseases and dangerous occurrences are to be reported to the HSE. It applies to all work activities, but not to all types of incidents. The incidents are to be reported using the OIR/9B and F2508A forms. These forms are to be completed and submitted to the local HSE-OSD office.
Prior to 1 April 1996 injuries and dangerous occurrences were reported on the OIR/9A form. This form was created under the Mineral Workings (Offshore Installations) Act 1971 and the Offshore Installations (Inspectors and Casualties) Regulations 1973.
The information submitted on the OIR/9A, OIR/9B and F2508A forms are recorded in a database, “ORION” (the former Sun Safety System), run by the HSE-OSD offices in Bootle, Liverpool.
The Sun Safety System (now ORION) was primarily developed to record incident data reported on the OIR/9A form. Other information is however recorded on the database, including details of inspections, investigations, prosecutions and the registration and location details of Offshore Installations. The OIR/9A form was first published in October 1990, and the Sun Safety System was implemented in 1st January 1991. The Sun Safety System does however contain some data on pre 1991 incidents (imported from previous systems maintained by the Safety Directorate of the Department of Energy), though not all fields on the OIR/9A form are available for this data. The Sun Safety System was decommissioned year 2000 and all data from 1991(incl.) was transferred to ORION.
Note that notification of hydrocarbon releases (voluntarily submitted on the OIR/12 form) are also recorded in a separate and specifically designed database which is maintained by the HSE-OSD offices in Bootle, Liverpool.
5.1 Available data For the purposes of this project HSE-OSD made available information from ORION on Excel spreadsheets, one per year for the period 1980-2001. Incidents categorised as “slips-trips-and-falls” were excluded. Each relevant incident was reported with the following parameters:
• Location name (name of installation) • Location type (Fixed attended or Fixed N.U.I.*) • Date of incident • Accident report type (incident category); coded, codes given in section 5.1.1 • Dangerous occurrence type; coded, codes given in Appendix A (see section 5.1.2) • Broad incident type; coded, codes given in section 5.1.3 • Incident notes (incident description, free text) *): Normally Unmanned Installation
A sample record is given below (example of incident reported under RIDDOR 95).
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Location name < Installation name >
Location type Fixed attended
Date of incident <Date>
Dangerous Failure offshore occurrence type
Broad incident type Lifting / crane operations
Incident notes Whilst lifting a 300kg flowline pipe spool from the cellar deck east lay-down area by crane, the load became snagged under a protruding structural beam causing the 1 tonne lifting sling to fail resulting in the load falling approx 20 ft to the deck. No personnel were injured, but the deck sustained a large gash. The area was barriered off pending inspection of the area and communication with the HSE.
It is a condition of the contract between the HSE and DNV that any information so obtained will only be exported in a non attributable form to protect confidentiality. That is, data exported to any type of database should not allow identification of the name of the installation, company, location, date or time of an incident. It will thus be impossible to pinpoint the installation or operator by any means.
The introduction of RIDDOR 95 offshore from 1/4/96 brought with it the use of Dangerous Occurrence (DO) type codes for the first time - DOs were recorded prior to this, but not against any specific coding and under different legislation (e.g. Mineral Workings (Offshore Installations) Act 1971).
The recording of Broad Incident Type (BIT) is held against earlier data and prior to RIDDOR 95 was actually recorded on the report form by the duty holder although post RIDDOR, it has been OSD who have coded BIT.
5.1.1 Incident category codes The following codes are used for the parameter Accident report type (or Incident category).
Code Description
1 Fatality
2 Major Injury
3 Over 3 day Injury
4 Dangerous Occurrence
5.1.2 Dangerous occurrence type codes A complete list of the codes used for the parameter Dangerous occurrence type (DO) is found in Appendix A. This field is only completed for category 4 incidents (“Dangerous Occurrences”) and only for incidents in the period from April 1996 to date (ref. RIDDOR 95).
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1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
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5.1.3 Broad incident type codes The following codes are used for the parameter Broad incident type (BIT). This field is only completed for category 1-3 incidents (Fatalities and Injuries) and only for incidents in the period from April 1996 to date (ref. RIDDOR 95).
Code Description
Loss of containment
Fire / explosion
Air transport
Sea transport
Slips / trips / falls
Falling objects
Handling goods / materials
Lifting / crane operations
Use of hand tools
Use of machinery
Exposure to harmful substances
Diving related
Electrical
Structural / foundation
Mooring
Radiation
Other
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5.2 Event classification and coding principles The WOAD concept of classifying events has been selected for the review work on the records received from HSE’s ORION. Hence the events are categorised according to the table below. It should be noted that not all types of events apply to fixed units.
Table 5 Event classification, WOAD
Type of event Explanation
Anchor failure Problems with anchor/anchor lines, mooring devices, winching equipment or fairleads (e.g. anchor dragging, breaking of mooring lines, loss of anchor(s), winch failures).
Blowout An uncontrolled flow of gas, oil or other fluids from the reservoir, i.e. loss of 1. barrier (i.e. hydrostatic head) or leak and loss of 2. barrier, i.e. BOP/DHSV.
Capsize Loss of stability resulting in overturn of unit, capsizing, or toppling of unit.
Collision Accidental contact between offshore unit and/or passing marine vessel when at least one of them is propelled or is under tow. Examples: tanker, cargo ship, fishing vessel. Also included are collisions with bridges, quays, etc., and vessels engaged in the oil and gas activity on other platforms than the platform affected, and between two offshore installations (to be coded as CN only when intended for close location).
Contact Collisions/accidental contacts between vessels engaged in the oil and gas activity on the platform affected, e.g. support/supply/stand-by vessels, tugs or helicopters, and offshore installations (floating or fixed). Also are included collisions between two offshore installations only when these are intended for close location.
Crane accident Any event caused by or involving cranes, derrick and drawworks, or any other lifting equipment.
Explosion Explosion
Falling load Falling load/dropped objects from crane, drill derrick, or any other lifting equipment or platform. Crane fall and lifeboats accidentally to sea and man overboard are also included.
Fire Fire.
Foundering Loss of buoyancy or unit sinking.
Grounding Floating installation in contact with the sea bottom.
Helicopter accident Accident with helicopter either on helideck or in contact with the installation.
Leakage Leakage of water into the unit or filling of shaft or other
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Type of event Explanation
compartments causing potential loss of buoyancy or stability problems.
List Uncontrolled inclination of unit.
Machinery failure Propulsion or thruster machinery failure (incl. control)
Off position Unit unintentionally out of its expected position or drifting out of control.
Spill/release “Loss of containment”. Release of fluid or gas to the surroundings from unit's own equipment/vessels/tanks causing (potential) pollution and/or risk of explosion and/or fire.
Structural damage Breakage or fatigue failures (mostly failures caused by weather, but not necessarily) of structural support and direct structural failures. "Punch through" also included.
Towing accident Towline failure or breakage
Well problem Accidental problem with the well, i.e. loss of one barrier (hydrostatic head) or other downhole problems.
Other Event other than specified above
The categorisation of the incidents has been performed according to a set of principles defined in the project in order to obtain consistency and to ease the coding work. In addition, guidelines for excluding incidents from the material have been established. Some examples of both categories are given below.
• Events coded as Falling load involve loads and objects, either rolling, leaning, tilting, falling, rotating, swinging, or sliding. Man over board is also included here.
• Maloperation of lifting equipment or technical failure leading to falling load is coded as Crane failure + Falling load.
• Events involving radiation from radioactive materials (causing injuries or not) are coded as Other.
• Events involving equipment or part of equipment bursting or blowing out, are coded as Spill/Release.
• Incidents that occur during maintenance indicating design shortcomings or inadequate procedures have been coded accordingly (crane failure, falling load, etc.).
• “Occupational Hazard” (OH) incidents, with personal injuries or not, are defined to be events which are not related to operations of equipment and events caused by obvious human errors during maintenance. Furthermore, events occurring during diving operations, which are not caused by platform related events, are coded as OH. In addition, injuries not caused by failure of equipment (e.g. squeezing/crushing fingers or hands in connection with pipe handling operations and no failure of lifting equipment) are coded as OH. The OH events have only been counted, but are excluded from the statistics (i.e. no frequencies).
• Recorded false ESDs and alarms are excluded from the data material. • “Slips, trips and falls” on the platform are excluded from the data material. • Prompt releases (no fire) of halon are excluded from the data material.
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5.3 Result of interrogation The information that was available for each incident has been reviewed and the chain of events obtained. The classification of events has been done according to the WOAD concept (see previous section). One accident may comprise a chain of consecutive events (accident outcomes or occurrences), e.g. a blowout resulting in explosion, fire and oil spill. This means that one single accident or incident may give rise to several occurrences. The total number of occurrences will thus be much higher than the total number of accidents recorded. When giving accident frequencies per type of event, these are generally presented as number of occurrences per unit per year (ref. sections 5.3.1- 5.3.8).
However, when presenting frequencies irrespective of type of event, the figures are given as number of accidents per unit per year (ref. Table 10 and Table 11).
The two following tables summarise the result of the interrogation of data available from ORION, i.e. the number of incidents per year. The available data material comprises a total of 5512 events (platform related events) giving rise to a total of 7086 occurrences. These events comprise accidents, hazardous situations and near-misses. As can be seen from the two tables below, no accidents are recorded on pumping platforms and further only a limited number of events on injection/riser and accommodation platforms.
It should be noted that in addition to the identified platform related events a total of 1660 “occupational hazard” events are reported, which are not included in the analysis.
Note that blank cells in the following tables denote that no accidents are recorded.
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Table 6 Fixed Units (I). UKCS. 1980-2001. No. of accidents. Source: ORION
Type of Installation
Year of event Drilling Production Wellhead Compression
1980-89 19 975 13 7
1990 8 169 9 1
1991 3 197 7 2
1992 317 9 6
1993 1 403 17 3
1994 9 471 9 5
1995 348 21 13
1996 1 359 22 8
1997 3 366 37 4
1998 1 362 36 2
1999 1 318 41 5
2000 405 40 2
2001 411 24
1990-99 27 3310 208 49
1980-2001 46 5101 285 58
19
Table 7 Fixed Units (II). UKCS, 1980-2001. No. of accidents. Source: ORION
Type of Installation
Year of event Pumping Injection/riser Accommodation All fixed, (I) & (II)
1980-89 1 6 1021
1990 1 188
1991 2 211
1992 2 1 335
1993 1 1 426
1994 2 496
1995 382
1996 1 391
1997 1 411
1998 1 402
1999 1 366
2000 1 448
2001 435
1990-99 6 8 3608
1980-2001 7 15 5512
20
Table 8 Fixed units (I). UKCS, 1980-2001. No. of occurrences. Source: ORION
Type of Installation
Type of event Drilling Production Wellhead Compression
Anchor failure
Blowout 8 1
Capsize
Collision 13 3
Contact 5 150 14
Crane 16 1337 34 5
Explosion 1 66
Falling object 16 1705 42 9
Fire 7 722 28 10
Foundering
Grounding
Helicopter 11 1
Leakage 1
List
Machinery
Off position
Spill/release 13 2248 192 29
Structural 11
Towing/towline
Well problem 2 288 10
Other 62 6
21
Table 9 Fixed units (II). UKCS. 1980-2001. No. of occurrences. Source: ORION
Type of Installation
Type of event Pumping Injection/ riser Accommodation All fixed, (I) & (II)
Anchor failure
Blowout 9
Capsize
Collision 1 17
Contact 1 4 174
Crane 1 1393
Explosion 67
Falling object 1 2 1775
Fire 4 5 776
Foundering
Grounding
Helicopter 12
Leakage 1
List
Machinery
Off position
Spill/release 3 2485
Structural 11
Towing/towline
Well problem 300
Other 68
The results from performing a statistical analysis of the data are shown below and in the following sub-sections. The exposure data used in the analysis are documented in chapter 4 of this report.
The tables below show the accident frequencies (i.e. number of accidents per unit-year) for all fixed units on the UKCS in 1980-2001.
22
Table 10 Fixed units (I). UKCS. 1980-2001. Accident frequencies (per unit year). Source: ORION
Type of Installation
Year of event Drilling Production Wellhead Compression
Average 1980-89 0.1152 1.5984 0.0861 0.1014
1990 0.4444 2.2237 0.2308 0.1250
1991 0.1667 2.4937 0.1556 0.2222
1992 3.9136 0.1875 0.6667
1993 0.0526 4.6860 0.3333 0.3000
1994 0.4737 5.1196 0.1607 0.5000
1995 3.7826 0.3684 1.1818
1996 0.0588 3.8602 0.3385 0.8889
1997 0.1667 3.8936 0.5286 0.3636
1998 0.0556 3.7320 0.5000 0.1818
1999 0.0556 3.3125 0.5190 0.4167
2000 4.1327 0.4762 0.1667
2001 4.1515 0.2824
Average 1990-99 0.1406 3.7359 0.3574 0.4900
Average 1980-2001 0.1201 3.0130 0.3160 0.3005
23
Table 11 Fixed Units (II). UKCS, 1980-2001. Accident frequencies (per unit year). Source: ORION
Type of Installation
Year of event Pumping Injection/ riser Accommodation All fixed, (I) & (II)
Average 1980-89 0.0222 0.1463 0.9273
1990 0.2000 1.2208
1991 0.3333 1.2788
1992 0.3333 0.1429 1.9591
1993 0.1250 0.1250 2.3152
1994 0.2222 2.5178
1995 1.9146
1996 0.1000 1.9073
1997 0.1000 1.9206
1998 0.0909 1.8273
1999 0.0909 1.6053
2000 0.0909 1.9064
2001 1.8354
Average 1990-99 0.0750 0.0920 1.8627
Average 1980-2001 0.0483 0.1000 1.5704
24
5.3.1 All fixed units In the following tables the number of occurrences and corresponding frequencies for all fixed units are given per year/period. N denotes number of occurrences and F denotes frequency, i.e. number of occurrences per unit and year. Blank cells denote no occurrences recorded (and hence no frequencies calculated).
Table 12 Fixed Units. UKCS, 1980-89, 1990, 1991, 1992. No. of occurrences and occurrence frequencies (per unit year). Source: ORION
Year/period
1980-89 1990 1991 1992
Type of event N F N F N F N F
Anchor failure
Blowout 5 4.5•10-3
Capsize
Collision 2 1.8•10-3 1 5.8•10-3
Contact 77 0.0699 12 0.0779 8 0.0485 6 0.0351
Crane 421 0.3824 63 0.4091 62 0.3758 69 0.4035
Explosion 32 0.0291 4 0.0260 6 0.0364 6 0.0351
Falling object 465 0.4223 68 0.4416 82 0.4970 92 0.5380
Fire 225 0.2044 34 0.2208 16 0.0970 73 0.4269
Foundering
Grounding
Helicopter 6 5.4•10-3 2 0.0130 1 6.1•10-3
Leakage 1 9.1•10-4
List
Machinery
Off position
Spill/release 210 0.1907 70 0.4545 74 0.4485 245 1.4327
Structural 1 9.1•10-4
Towing/towline
Well problem 20 0.0182 2 0.0130 2 0.0121 9 0.0526
Other 5 4.5•10-3 6 0.0364 3 0.0175
25
Table 13 Fixed Units. UKCS, 1993-1996. No. of occurrences and occurrence frequencies (per unit year). Source: ORION
Year
1993 1994 1995 1996
Type of event N F N F N F N F
Anchor failure
Blowout 2 0.0101 1 4.9•10-3
Capsize
Collision 1 5.4•10-3 2 0.0102 3 0.1508
Contact 6 0.0326 10 0.0508 12 0.0603 10 0.0488
Crane 70 0.3804 94 0.4772 78 0.3920 68 0.3317
Explosion 1 5.4•10-3 3 0.0152 1 5.0•10-3 1 4.9•10-3
Falling object 88 0.4783 126 0.6396 101 0.5075 94 0.4585
Fire 47 0.2554 66 0.3350 47 0.2362 34 0.1659
Foundering
Grounding
Helicopter 1 5.4•10-3 1 5.0•10-3
Leakage
List
Machinery
Off position
Spill/release 187 1.0163 320 1.6244 217 1.0905 162 0.7902
Structural 3 0.0163 2 0.0101 1 4.9•10-3
Towing/towline
Well problem 2 0.0109 13 0.0660 8 0.0402 50 0.2439
Other 4 0.0217 7 0.0355 8 0.0402 3 0.0146
26
Table 14 Fixed Units. UKCS, 1997-1999. No. of occurrences and occurrence frequencies (per unit year). Source: ORION
Year
1997 1998 1999
Type of event N F N F N F
Anchor failure
Blowout
Capsize
Collision 1 4.7•10-3 2 9.1•10-3 3 0.0132
Contact 9 0.0421 5 0.0227 8 0.0351
Crane 93 0.4346 104 0.4727 80 0.3509
Explosion 7 0.0327 1 4.5•10-3 2 8.8•10-3
Falling object 117 0.5467 134 0.6091 126 0.5526
Fire 48 0.2243 43 0.1955 41 0.1798
Foundering
Grounding
Helicopter
Leakage
List
Machinery
Off position
Spill/release 199 0.9299 196 0.8909 172 0.7544
Structural 1 4.7•10-3 1 4.5•10-3
Towing/towline
Well problem 43 0.2009 44 0.2000 38 0.1667
Other 2 9.3•10-3 5 0.0227 5 0.0219
27
Table 15 Fixed Units. UKCS, 2000, 2001, 1990-99, 1980-2001. No. of occurrences and occurrence frequencies (per unit year). Source: ORION
Year Period
2000 2001 1990-99 1980-2001
Type of event N F N F N F N F
Anchor failure
Blowout 1 4.2•10-3 3 1.5•10-3 9 2.6•10-3
Capsize
Collision 5 0.0213 14 7.2•10-3 21 6.0•10-3
Contact 8 0.0340 3 0.0127 86 0.0444 174 0.0496
Crane 90 0.3830 100 0.4219 781 0.4032 1393 0.3969
Explosion 3 0.0128 32 0.0165 67 0.0191
Falling object 137 0.5830 145 0.6118 1028 0.5307 1775 0.5057
Fire 50 0.2128 52 0.2194 449 0.2318 776 0.2211
Foundering
Grounding
Helicopter 1 4.2•10-3 5 2.6•10-3 12 3.4•10-3
Leakage 1 2.8•10-4
List
Machinery
Off position
Spill/release 213 0.9064 220 0.9283 1842 0.9510 2485 0.7080
Structural 2 8.5•10-3 8 4.1•10-3 11 3.1•10-3
Towing/towline
Well problem 34 0.1447 35 0.1477 211 0.1089 300 0.0855
Other 15 0.0638 5 0.0211 43 0.0222 68 0.0194
28
5.3.2 Drilling units The recorded number and type of occurrences and the corresponding frequencies are given for fixed drilling units in the following table. N denotes number of occurrences and F denotes frequency, i.e. number of occurrences per unit and year.
Table 16 Drilling units. UKCS, 1980-2001. No. of occurrences and occurrence frequencies (per unit year). Source: ORION
Year Type of event N F
Average 1980-89
Contact 4 0.0242
Crane 6 0.0364
Explosion 1 6.1•10-3
Falling object 6 0.0364
Fire 3 0.0182
Spill/release 5 0.0303
1990 Crane 5 0.2778
Falling object 3 0.1667
Fire 1 0.0556
Spill/release 2 0.1111
1991 Contact 1 0.0556
Crane 1 0.0556
Spill/release 1 0.0556
1993 Spill/release 1 0.0526
1994 Crane 1 0.0526
Falling object 1 0.0526
Fire 3 0.1579
Spill/release 4 0.2105
Well problem 1 0.0526
1996 Falling object 1 0.0588
1997 Crane 1 0.0556
Falling object 3 0.1667
1998 Crane 1 0.0556
Falling object 1 0.0556
Well problem 1 0.0556
1999 Crane 1 0.0556
Falling object 1 0.0556
Year Type of event N F
Average 1990-99
Contact 1 5.5•10-3
Crane 10 0.0549
Falling object 10 0.0549
Fire 4 0.0220
Spill/release 8 0.0440
Well problem 2 0.0110
Average 1980-2001
Contact 5 0.0131
Crane 16 0.0418
Explosion 1 2.6•10-3
Falling object 16 0.0418
Fire 7 0.0183
Spill/release 13 0.0339
Well problem 2 5.2•10-3
29
5.3.3 Production units In the following tables the number of occurrences and corresponding frequencies for fixed production units area given per year/period. N denotes number of occurrences and F denotes frequency, i.e. number of occurrences per unit and year. Blank cells denote no occurrences recorded (and hence no frequencies calculated).
Table 17 Production Units. UKCS, 1980-89, 1990-92. No. of occurrences and occurrence frequencies (per unit year). Source: ORION
Year/period
1980-89 1990 1991 1992
Type of event N F N F N F N F
Anchor failure
Blowout 4 6.6•10-3
Capsize
Collision 2 3.3•10-3 1 0.0116
Contact 70 0.1148 11 0.1447 8 0.1013 4 0.0465
Crane 409 0.6705 53 0.6974 59 0.7468 66 0.7674
Explosion 31 0.0508 4 0.0526 6 0.0759 6 0.0698
Falling object 450 0.7377 57 0.7500 78 0.9873 89 1.0349
Fire 215 0.3525 32 0.4211 14 0.1772 70 0.8140
Foundering
Grounding
Helicopter 5 8.2•10-3 2 0.0263 1 0.0127
Leakage 1 1.6•10-3
List
Machinery
Off position
Spill/release 199 0.3262 65 0.8553 68 0.8608 230 2.6744
Structural 1 1.6•10-3
Towing/towline
Well problem 19 0.0311 2 0.0263 2 0.0253 9 0.1047
Other 5 8.2•10-3 6 0.0759 3 0.0349
30
Table 18 Production Units. UKCS, 1993-1996. No. of occurrences and occurrence frequencies (per unit year). Source: ORION
Year
1993 1994 1995 1996
Type of event N F N F N F N F
Anchor failure
Blowout 2 0.0217 1 0.0108
Capsize
Collision 1 0.0123 2 0.0218 2 0.0217
Contact 4 0.0494 8 0.0870 11 0.1196 8 0.0860
Crane 68 0.8395 92 1.0000 76 0.8261 65 0.6989
Explosion 1 0.0123 3 0.0326 1 0.0109 1 0.0108
Falling object 86 1.0617 124 1.3478 98 1.0652 88 0.9462
Fire 46 0.5679 60 0.6522 38 0.4130 34 0.3656
Foundering
Grounding
Helicopter 1 0.0123 1 0.0109
Leakage
List
Machinery
Off position
Spill/release 174 2.1481 304 3.3043 197 2.1413 147 1.5806
Structural 3 0.0370 2 0.0217 1 0.0108
Towing/towline
Well problem 2 0.0247 12 0.1304 8 0.087 50 0.5376
Other 4 0.0494 7 0.0761 7 0.0761 3 0.0323
31
Table 19 Production Units. UKCS, 1997-1999. No. of occurrences and occurrence frequencies (per unit year). Source: ORION
Year
1997 1998 1999
Type of event N F N F N F
Anchor failure
Blowout
Capsize
Collision 1 0.0106 2 0.0206 2 0.0208
Contact 8 0.0851 5 0.0515 5 0.0521
Crane 86 0.9149 100 1.0309 76 0.7917
Explosion 7 0.0745 1 0.0103 2 0.0208
Falling object 107 1.1383 130 1.3402 119 1.2396
Fire 44 0.4681 40 0.4124 35 0.3646
Foundering
Grounding
Helicopter
Leakage
List
Machinery
Off position
Spill/release 172 1.8298 167 1.7216 141 1.4688
Structural 1 0.0106 1 0.0103
Towing/towline
Well problem 43 0.4574 40 0.4124 37 0.3854
Other 2 0.0213 4 0.0412 3 0.0313
32
Table 20 Production Units. UKCS, 2000, 2001, 1990-99, 1980-2001. No. of occurrences and occurrence frequencies (per unit year). Source: ORION
Year Period
2000 2001 1990-99 1980-2001
Type of event N F N F N F N F
Anchor failure
Blowout 1 0.0101 3 3.4•10-3 8 4.7•10-3
Capsize
Collision 4 0.0408 11 0.1242 17 0.0100
Contact 6 0.0612 2 0.0202 72 0.0813 150 0.0886
Crane 89 0.9082 98 0.9899 741 0.8363 1337 0.7897
Explosion 3 0.0306 32 0.0361 66 0.0390
Falling object 136 1.3878 143 1.4444 976 1.1016 1705 1.0071
Fire 49 0.5000 45 0.4545 413 0.4661 722 0.4265
Foundering
Grounding
Helicopter 1 0.0101 5 5.6•10-3 11 6.5•10-3
Leakage 1 5.9•10-4
List
Machinery
Off position
Spill/release 177 1.8061 207 2.0909 1665 1.8792 2248 1.3278
Structural 2 0.0204 8 9.0•10-3 11 6.5•10-3
Towing/towline
Well problem 32 0.3265 32 0.3232 205 0.2314 288 0.1701
Other 13 0.1327 5 0.0505 39 0.0440 62 0.0366
33
5.3.4 Wellhead units In the following table the number of occurrences and corresponding frequencies for fixed (production) wellhead units area given per year/period. N denotes number of occurrences and F denotes frequency, i.e. number of occurrences per unit and period. Blank cells denote no occurrences recorded (and hence no frequencies calculated).
Table 21 Wellhead Units. UKCS, 1980-89, 1990-92. No. of occurrences and occurrence frequencies (per unit year). Source: ORION
Year/period
1980-89 1990 1991 1992
Type of event N F N F N F N F
Anchor failure
Blowout 1 6.6•10-3
Capsize
Collision
Contact 1 6.6•10-3 1 0.0256
Crane 3 0.0199 5 0.1282 2 0.0444 3 0.0588
Explosion
Falling object 4 0.0265 7 0.1795 3 0.0667 3 0.0588
Fire 4 0.0265 1 0.0196
Foundering
Grounding
Helicopter
Leakage
List
Machinery
Off position
Spill/release 4 0.0265 3 0.0769 5 0.1111 13 0.2549
Structural
Towing/towline
Well problem 1 6.6•10-3
Other
34
Table 22 Wellhead Units. UKCS, 1993-1996. No. of occurrences and occurrence frequencies (per unit year). Source: ORION
Year
1993 1994 1995 1996
Type of event N F N F N F N F
Anchor failure
Blowout
Capsize
Collision 1 0.0175
Contact 1 0.0208 1 0.0179 1 0.0175 2 0.0308
Crane 1 0.0208 1 0.0179 1 0.0175 3 0.0462
Explosion
Falling object 1 0.0208 1 0.0179 1 0.0175 5 0.0769
Fire 2 0.0357 3 0.0526
Foundering
Grounding
Helicopter
Leakage
List
Machinery
Off position
Spill/release 7 0.1458 7 0.125 14 0.2456 15 0.2308
Structural
Towing/towline
Well problem
Other 1 0.0175
35
Table 23 Wellhead Units. UKCS, 1997-1999. No. of occurrences and occurrence frequencies (per unit year). Source: ORION
Year
1997 1998 1999
Type of event N F N F N F
Anchor failure
Blowout
Capsize
Collision 1 0.0139 1 0.0127
Contact 1 0.0143 3 0.0380
Crane 6 0.0857 3 0.0417 3 0.0380
Explosion
Falling object 6 0.0857 3 0.0417 5 0.0633
Fire 3 0.0429 3 0.0417 4 0.0506
Foundering
Grounding
Helicopter
Leakage
List
Machinery
Off position
Spill/release 25 0.3571 26 0.3611 26 0.3291
Structural
Towing/towline
Well problem 3 0.0417 1 0.0127
Other 1 0.0139 2 0.0253
36
Table 24 Wellhead Units. UKCS, 2000, 2001, 1990-99, 1980-2001. No. of occurrences and occurrence frequencies (per unit year). Source: ORION
Year Period
2000 2001 1990-99 1980-2001
Type of event N F N F N F N F
Anchor failure
Blowout 1 1.1•10-3
Capsize
Collision 3 5.2•10-3 3 3.3•10-3
Contact 2 0.0238 1 0.0118 10 0.0172 14 0.0155
Crane 1 0.0119 2 0.0235 28 0.0481 34 0.0377
Explosion
Falling object 1 0.0119 2 0.0235 35 0.0601 42 0.0466
Fire 1 0.0119 7 0.0824 16 0.0275 28 0.0310
Foundering
Grounding
Helicopter
Leakage
List
Machinery
Off position
Spill/release 34 0.4048 13 0.1529 141 0.2423 192 0.2129
Structural
Towing/towline
Well problem 2 0.0238 3 0.0353 4 6.9•10-3 10 0.0111
Other 2 0.0238 4 6.9•10-3 6 6.7•10-3
37
5.3.5 Compression units In the following table the number of occurrences and corresponding frequencies for fixed compression units are given per year/period. N denotes number of occurrences and F denotes frequency, i.e. number of occurrences per unit and period. Blank cells denote no occurrences recorded (and hence no frequencies calculated).
Table 25 Compression Units. UKCS, 1980-89, 1990-92. No. of occurrences and occurrence frequencies (per unit year). Source: ORION
Year/period
1980-89 1990 1991 1992
Type of event N F N F N F N F
Anchor failure
Blowout
Capsize
Collision
Contact
Crane 2 0.0290 1 0.1111
Explosion
Falling object 3 0.0435 1 0.1250 1 0.1111
Fire 1 0.0145 1 0.1111
Foundering
Grounding
Helicopter 1 0.0145
Leakage
List
Machinery
Off position
Spill/release 1 0.0145 1 0.1111 2 0.2222
Structural
Towing/towline
Well problem
Other
38
Table 26 Compression Units. UKCS, 1993-1996. No. of occurrences and occurrence frequencies (per unit year). Source: ORION
Year
1993 1994 1995 1996
Type of event N F N F N F N F
Anchor failure
Blowout
Capsize
Collision
Contact
Crane 1 0.1000 1 0.0909
Explosion
Falling object 1 0.1000 2 0.1818
Fire 1 0.1000 6 0.5455
Foundering
Grounding
Helicopter
Leakage
List
Machinery
Off position
Spill/release 5 0.5000 4 0.4000 6 0.5455
Structural
Towing/towline
Well problem
Other
39
Table 27 Compression Units. UKCS, 1997-1999. No. of occurrences and occurrence frequencies (per unit year). Source: ORION
Year
1997 1998 1999
Type of event N F N F N F
Anchor failure
Blowout
Capsize
Collision
Contact
Crane
Explosion
Falling object 1 0.0909
Fire 1 0.0833
Foundering
Grounding
Helicopter
Leakage
List
Machinery
Off position
Spill/release 2 0.1818 2 0.1818 4 0.3333
Structural
Towing/towline
Well problem
Other
40
Table 28 Compression Units. UKCS, 2000, 2001, 1990-99, 1980-2001. No. of occurrences and occurrence frequencies (per unit year). Source: ORION
Year Period
2000 2001 1990-99 1980-2001
Type of event N F N F N F N F
Anchor failure
Blowout
Capsize
Collision
Contact
Crane 3 0.0300 5 0.0259
Explosion
Falling object 6 0.0600 9 0.0466
Fire 9 0.0900 10 0.0518
Foundering
Grounding
Helicopter 1 5.2•10-3
Leakage
List
Machinery
Off position
Spill/release 2 0.1667 26 0.2600 29 0.1503
Structural
Towing/towline
Well problem
Other
41
5.3.6 Pumping units No accidents are recorded on pumping platforms in the ORION database, and hence the overall calculated occurrence frequency is 0.
5.3.7 Injection/riser units A low number of events are recorded on injection/riser type of installations in the ORION database for the period 1980-2001. The recorded number and type of occurrences and the corresponding frequencies are given in the following table. N denotes number of occurrences and F denotes frequency, i.e. number of occurrences per unit and year.
Table 29 Injection/riser units. UKCS. 1980-2001. No. of occurrences per unit year. Source: ORION
Year Type of event N F
Average 1980-89
Falling object 1 0.0222
Fire 1 0.0222
1990 Fire 1 0.2000
1991 Fire 2 0.3333
1993 Contact 1 0.1250
Average 1990-99
Contact 1 0.0125
Fire 3 0.0375
Average 19802001
Contact 1 6.9•10-3
Falling object 1 6.9•10-3
Fire 4 0.0272
42
5.3.8 Accommodation units The recorded number and type of occurrences and the corresponding frequencies for fixed accommodation units are given in the following table. N denotes number of occurrences and F denotes frequency, i.e. number of occurrences per unit and year.
Table 30 Accommodation units. UKCS. 1980-2001. No. of occurrences per unit year. Source: ORION
Year Type of event N F
Average 1980-89
Contact 2 0.0488
Crane 1 0.0244
Falling object 1 0.0244
Fire 2 0.0488
Spill/release 1 0.0244
1992 Contact 1 0.1429
1993 Fire 1 0.1250
1994 Contact 1 0.1111
Spill/release 1 0.1111
1996 Fire 1 0.1000
1997 Fire 1 0.1000
1998 Spill/release 1 0.0909
1999 Falling object 1 0.0909
2000 Collision 1 0.0909
Average 1990-99
Contact 2 0.0230
Falling object 1 0.0115
Fire 2 0.0230
Spill/release 2 0.0230
Average 19802001
Collision 1 6.7•10-3
Contact 4 0.0267
Crane 1 6.7•10-3
Falling object 2 0.0133
Fire 5 0.0333
Spill/release 3 0.0200
43
44
6 WOAD One of the main sources for offshore accident information for public use is the Worldwide Offshore Accident Databank (WOAD) operated by Det Norske Veritas (DNV). WOAD contains some 4.300 events from the period 1970-2001, derived mainly from public-domain sources such as Lloyds Casualty Reports, newspapers and official publications. Most of the data is from the UK and Norwegian Sectors and the US Gulf of Mexico. Exposure data is also provided, allowing accident rates to be calculated for different accident types, unit types, geographical locations, degrees of damage, etc.
6.1 Available data The WOAD database contains information on accidents for fixed units on the UKCS since 1970. Each record in the database contains information on a number of aspects concerning the installation and the accident. Below is given a sample record from the database with a selection of parameters, only.
Date 930717
Time 2100 hrs
Type Jacket (combined drilling/production)
Name <Rig name>
Operation mode Production
Chain of events Spill/release (of diesel) – fire
No. of injuries 0
No. of fatalities 0
Degree of damage Insignificant
No. of evacuees 274 called to muster
Description A fire broke out on the platform with a crew of 274 who were called to muster stations and production was temporarily suspended for about one hour. Black smoke was spotted coming out from a turbine. The fire was resulting from diesel ignition in the exhaust stack. It is unknown how diesel fuel found its way into the exhaust system. The turbine was put out of service.
45
6.2 Result of interrogation The database was interrogated for retrieval of relevant records and the search resulted in 159 records matching the defined search criterion (period: 1980-2001, type of unit: fixed, geographical area: North Sea, UK Shelf) giving rise to a total of 203 occurrences. These events comprise mainly major accidents, but also some hazardous situations and near-misses are recorded.
The following two tables summarises the results of the search. Note that blank cells in the following tables denote that no accidents are recorded.
Table 31 Fixed Units (I). UKCS, 1980-2001. No. of accidents. Source: WOAD
Type of Installation
Year of event Drilling Production Wellhead Compression
1980-89 39 3 2
1990 16
1991 14
1992 14
1993 17
1994 11
1995 13 1
1996 4
1997 3
1998 4
1999 5
2000 9
2001 2
1990-99 101 1
1980-2001 151 4 2
46
Table 32 Fixed Units (II). UKCS, 1980-2001. No. of accidents. Source: WOAD
Type of Installation
Year of event Pumping Injection/riser Accommodation All fixed, (I) & (II)
1980-89 2 46
1990 16
1991 14
1992 14
1993 17
1994 11
1995 14
1996 4
1997 3
1998 4
1999 5
2000 9
2001 2
1990-99 102
1980-2001 2 159
The 159 accidents listed in the two previous tables include a total of 203 occurrences as listed in Table 33 and Table 34.
47
Table 33 Fixed units (I). UKCS, 1980-2001. No. of occurrences. Source: WOAD
Type of Installation
Type of event Drilling Production Wellhead Compression
Anchor failure
Blowout 3 1
Capsize
Collision 6 2
Contact 11
Crane 9
Explosion 18
Falling object 15
Fire 27 1
Foundering
Grounding
Helicopter 2 1
Leakage
List 1
Machinery
Off position
Spill/release 80 2 1
Structural 7
Towing/towline
Well problem 7
Other 7
48
Table 34 Fixed units (II). UKCS, 1980-2001. No. of occurrences. Source: WOAD
Type of Installation
Type of event Pumping Injection/ riser Accommodation All fixed, (I) & (II)
Anchor failure
Blowout 4
Capsize
Collision 8
Contact 11
Crane 9
Explosion 18
Falling object 15
Fire 1 29
Foundering
Grounding
Helicopter 3
Leakage
List 1
Machinery
Off position
Spill/release 83
Structural 1 8
Towing/towline
Well problem 7
Other 7
The results from performing a statistical analysis of the data are shown below and in the following sub-sections. The exposure data used in the analysis are documented in chapter 4 of this report
When giving accident frequencies per type of event, these are generally presented as number of occurrences per unit per year (ref. sections 6.2.1-6.2.8).
However, when presenting frequencies irrespective of type of event, the figures are given as number of accidents per unit per year (ref. the two following tables).
The table below shows the accident frequencies (i.e. number of accidents per unit year) for all fixed units on the UKCS in 1980-2001. Blank cells denote no occurrences recorded (and hence no frequencies calculated).
49
Table 35 Fixed units (I). UKCS. 1980-2001. Accident frequencies (per unit year). Source: WOAD
Type of Installation
Year of event Drilling Production Wellhead Compression
Average 1980-89 0.0639 0.0199 0.0290
1990 0.2105
1991 0.1772
1992 0.1728
1993 0.1977
1994 0.1196
1995 0.1413 0.0175
1996 0.0429
1997 0.0319
1998 0.0412
1999 0.0521
2000 0.0918
2001 0.0202
Average 1990-99 0.1140 1.7•10-3
Average 1980-2001 0.0892 4.4•10-3 0.0104
50
Table 36 Fixed Units (II). UKCS, 1980-2001. Accident frequencies (per unit year). Source: WOAD
Type of Installation
Year of event Pumping Injection/ riser Accommodation All fixed, (I) & (II)
Average 1980-89 0.0488 0.0418
1990 0.1039
1991 0.0848
1992 0.0819
1993 0.0924
1994 0.0558
1995 0.0704
1996 0.0195
1997 0.0140
1998 0.0182
1999 0.0219
2000 0.0383
2001 8.4•10-3
Average 1990-99 0.0527
Average 1980-2001 0.0133 0.0453
51
6.2.1 All fixed units In the following tables the number of occurrences and corresponding frequencies for all fixed units are given per year/period. N denotes number of occurrences and F denotes frequency, i.e. number of occurrences per unit and year. Blank cells denote no occurrences recorded (and hence no frequencies calculated).
Table 37 Fixed Units. UKCS, 1980-89, 1990, 1991, 1992. No. of occurrences and occurrence frequencies (per unit year). Source: WOAD
Year/period
1980-89 1990 1991 1992
Type of event N F N F N F N F
Anchor failure
Blowout 3 2.7•10-3
Capsize
Collision 1 9.1•10-4
Contact 5 4.5•10-3 3 0.0195 1 6.1•10-3 2 0.0117
Crane 4 3.6•10-3 1 6.1•10-3
Explosion 10 9.1•10-3 3 0.0195 2 0.0117
Falling object 5 4.5•10-3 1 5.8•10-3
Fire 11 0.0100 2 0.0130 2 0.0117
Foundering
Grounding
Helicopter 2 1.8•10-3 1 5.8•10-3
Leakage
List 1 9.1•10-4
Machinery
Off position
Spill/release 20 0.0182 7 0.0455 10 0.0606 6 0.0351
Structural 4 3.6•10-3 1 6.1•10-3 1 5.8•10-3
Towing/towline
Well problem 3 2.7•10-3
Other 1 9.1•10-4 2 0.0121
52
Table 38 Fixed Units. UKCS, 1993-1996. No. of occurrences and occurrence frequencies (per unit year). Source: WOAD
Year
1993 1994 1995 1996
Type of event N F N F N F N F
Anchor failure
Blowout 1 5.1•10-3
Capsize
Collision 1 5.4•10-3 1 5.1•10-3 3 0.0151 1 4.9•10-3
Contact
Crane 2 0.0109 1 5.1•10-3
Explosion 1 5.4•10-3 1 5.1•10-3 1 4.9•10-3
Falling object 4 0.0217 1 5.1•10-3 1 5.0•10-3 1 4.9•10-3
Fire 2 0.0109 2 0.0102 5 0.0251
Foundering
Grounding
Helicopter
Leakage
List
Machinery
Off position
Spill/release 10 0.0543 9 0.0457 6 0.0302 1 4.9•10-3
Structural 1 5.0•10-3
Towing/towline
Well problem
Other 1 5.4•10-3 2 0.0101
53
Table 39 Fixed Units. UKCS, 1997-1999. No. of occurrences and occurrence frequencies (per unit year). Source: WOAD
Year
1997 1998 1999
Type of event N F N F N F
Anchor failure
Blowout
Capsize
Collision 1 4.5•10-3
Contact
Crane 1 4.7•10-3
Explosion
Falling object 1 4.7•10-3 1 4.4•10-3
Fire 2 9.1•10-3 1 4.4•10-3
Foundering
Grounding
Helicopter
Leakage
List
Machinery
Off position
Spill/release 1 4.7•10-3 3 0.0136 3 0.0132
Structural 1 4.4•10-3
Towing/towline
Well problem 1 4.4•10-3
Other 1 4.7•10-3
54
Table 40 Fixed Units. UKCS, 2000, 2001, 1990-99, 1980-2001. No. of occurrences and occurrence frequencies (per unit year). Source: WOAD
Year Period
2000 2001 1990-99 1980-2001
Type of event N F N F N F N F
Anchor failure
Blowout 1 5.2•10-4 4 1.1•10-3
Capsize
Collision 7 3.6•10-3 8 2.3•10-3
Contact 6 3.1•10-3 11 3.1•10-3
Crane 5 2.6•10-3 9 2.6•10-3
Explosion 8 4.1•10-3 18 5.1•10-3
Falling object 10 5.2•10-3 15 4.3•10-3
Fire 1 4.3•10-3 1 4.2•10-3 16 8.3•10-3 29 8.3•10-3
Foundering
Grounding
Helicopter 1 5.2•10-4 3 8.5•10-4
Leakage
List 1 2.8•10-4
Machinery
Off position
Spill/release 6 0.0255 1 4.2•10-3 56 0.0289 83 0.0236
Structural 4 2.1•10-3 8 2.3•10-3
Towing/towline
Well problem 2 8.5•10-3 1 1 5.2•10-4 7 2.0•10-3
Other 4.2•10-3 6 3.1•10-3 7 2.0•10-3
6.2.2 Drilling units No accidents are recorded on drilling platforms in the WOAD database in the period 1980-2001, and hence the overall calculated occurrence frequency is 0.
55
6.2.3 Production units In the following tables the number of occurrences and corresponding frequencies for fixed production units are given per year/period. N denotes number of occurrences and F denotes frequency, i.e. number of occurrences per unit and year. Blank cells denote no occurrences recorded (and hence no frequencies calculated).
Table 41 Production Units. UKCS, 1980-89, 1990, 1991, 1992. No. of occurrences and occurrence frequencies (per unit year). Source: WOAD
Year/period
1980-89 1990 1991 1992
Type of event N F N F N F N F
Anchor failure
Blowout 2 3.3•10-3
Capsize
Collision
Contact 5 8.2•10-3 3 0.0395 1 0.0126 2 0.0247
Crane 4 6.6•10-3 1 0.0126
Explosion 10 0.0164 3 0.0395 2 0.0247
Falling object 5 8.2•10-3 1 0.0123
Fire 9 0.0148 2 0.0263 2 0.0247
Foundering
Grounding
Helicopter 1 1.6•10-3 1 0.0123
Leakage
List 1 1.6•10-3
Machinery
Off position
Spill/release 17 0.0279 7 0.0921 10 0.126 6 0.0741
Structural 3 4.9•10-3 1 0.0126 1 0.0123
Towing/towline
Well problem 3 4.9•10-3
Other 1 1.6•10-3 2 0.0253
56
Table 42 Production Units. UKCS, 1993-1996. No. of occurrences and occurrence frequencies (per unit year). Source: WOAD
Year
1993 1994 1995 1996
Type of event N F N F N F N F
Anchor failure
Blowout 1 0.0109
Capsize
Collision 1 0.0116 1 0.0109 2 0.0217 1 0.0108
Contact
Crane 2 0.0233 1 0.0109
Explosion 1 0.0116 1 0.0109 1 0.0108
Falling object 4 0.0465 1 0.0109 1 0.0109 1 0.0108
Fire 2 0.0233 2 0.0217 5 0.0543
Foundering
Grounding
Helicopter
Leakage
List
Machinery
Off position
Spill/release 10 0.1163 9 0.0978 6 0.0652 1 0.0108
Structural 1 0.0109
Towing/towline
Well problem
Other 1 0.0116 2 0.0217
57
Table 43 Production Units. UKCS, 1997-1999. No. of occurrences and occurrence frequencies (per unit year). Source: WOAD
Year
1997 1998 1999
Type of event N F N F N F
Anchor failure
Blowout
Capsize
Collision 1 0.0103
Contact
Crane 1 0.0106
Explosion
Falling object 1 0.0106 1 0.0104
Fire 2 0.0206 1 0.0104
Foundering
Grounding
Helicopter
Leakage
List
Machinery
Off position
Spill/release 1 0.0106 3 0.0309 3 0.0313
Structural 1 0.0104
Towing/towline
Well problem 1 0.0104
Other 1 0.0106
58
Table 44 Production Units. UKCS, 1990-99, 1980-2001. No. of occurrences and occurrence frequencies (per unit year). Source: WOAD
Year Period
2000 2001 1990-99 1980-2001
Type of event N F N F N F N F
Anchor failure
Blowout 1 1.1•10-3 3 1.8•10-3
Capsize
Collision 6 6.8•10-3 6 3.5•10-3
Contact 6 6.8•10-3 11 6.5•10-3
Crane 5 5.6•10-3 9 5.3•10-3
Explosion 8 9.0•10-3 18 0.0106
Falling object 10 0.0113 15 8.9•10-3
Fire 1 0.0102 1 0.0101 16 0.0181 27 0.0159
Foundering
Grounding
Helicopter 1 1.1•10-3 2 1.2•10-3
Leakage
List 1 5.9•10-4
Machinery
Off position
Spill/release 6 0.0612 1 0.0101 56 0.0632 80 0.0473
Structural 4 4.5•10-3 7 4.1•10-3
Towing/towline
Well problem 2 0.0204 1 0.0101 1 1.1•10-3 7 4.1•10-3
Other 6 6.8•10-3 7 4.1•10-3
59
6.2.4 Wellhead units A low number of events, 5 in total, are recorded on fixed (production) wellhead units in the WOAD database for the period 1980-2001. The recorded number and type of occurrences and the corresponding frequencies are given in the following table. N denotes number of occurrences and F denotes frequency, i.e. number of occurrences per unit and year.
Table 45 Wellhead units. UKCS, 1980-2001. No. of occurrences and occurrence frequencies (per unit year). Source: WOAD
Year Type of event N F
Average 1980-89
Blowout 1 6.6•10-3
Collision 1 6.6•10-3
Spill/release 2 0.0132
1995 Collision 1 0.0175
Average 1990-99
Collision 1 1.7•10-3
Average 19802001
Blowout 1 1.1•10-3
Collision 2 2.2•10-3
Spill/release 2 2.2•10-3
6.2.5 Compression units A low number of events, 2 in total and both in the period 1980-89 (3 occurrences), are recorded on fixed compression units in the WOAD database. The recorded number and type of occurrences and the corresponding frequencies are given in the following table. N denotes number of occurrences and F denotes frequency, i.e. number of occurrences per unit and year.
Table 46 Compression units. UKCS, 1980-2001. No. of occurrences and occurrence frequencies (per unit year). Source: WOAD
Year Type of event N F
Average 1980-89
Fire 1 0.0145
Helicopter 1 0.0145
Spill/release 1 0.0145
Average 19802001
Fire 1 5.2•10-3
Helicopter 1 5.2•10-3
Spill/release 1 5.2•10-3
60
6.2.6 Pumping units No accidents are recorded on fixed pumping platforms in the WOAD database in the period 19802001, and hence the overall calculated occurrence frequency is 0.
6.2.7 Injection/riser units No accidents are recorded on injection or fixed riser platforms in the WOAD database in the period 1980-2001, and hence the overall calculated occurrence frequency is 0.
6.2.8 Accommodation units A low number of events, 2 in total and both in the period 1980-89, are recorded on fixed accommodation units in the WOAD database. The recorded number and type of occurrences and the corresponding frequencies are given in the following table. N denotes number of occurrences and F denotes frequency, i.e. number of occurrences per unit and year.
Table 47 Accommodation units. UKCS, 1980-2001. No. of occurrences and occurrence frequencies (per unit year). Source: WOAD
Year Type of event N F
Average 1980-89
Fire 1 0.0244
Structural 1 0.0244
Average 19802001
Fire 1 6.7•10-3
Structural 1 6.7•10-3
61
62
7 BLOWOUT DATABASE The database was interrogated and the following query was set up for searching for relevant records in the database:
Date > Date(1980.1.1) AND Country=’UK’
Ten records matched this query, but only 4 records occurred on fixed units (the remaining ones on floating platforms). All 4 accidents were also recorded in WOAD. Hence, no separate frequencies are calculated here.
63
64
8 ACCIDENT STATISTICS By combining and merging the results from the interrogation of the two databases, ORION and WOAD, the accident/occurrence frequencies for floating units in the UKCS in the period 19802001 are estimated. All tables in this chapter present the number of accidents/occurrences with corresponding frequencies per type of fixed unit, per year and the whole period 1980-2001. The source ORION&WOAD refers to the database obtained by pooling the databases ORION and WOAD and removing the overlapping records.
8.1 Accident frequencies, All databases combined In this section the accident frequencies for floating units in the UKCS in the period 1980-2001 are presented. The following tables give the number of accidents and corresponding frequencies per type of fixed unit, period and data source. N denotes number of occurrences and F denotes frequency, i.e. number of occurrences per unit and year. Blank cells denote no occurrences recorded (and hence no frequencies calculated).
Table 48 Fixed Units (I). UKCS, 1980-2001. No. of accidents and accident frequencies (per unit year). Source: ORION&WOAD
Type of installation
Drilling Production Wellhead Compression
Year/period N F N F N F N F
1980-89 19 0.1152 995 1.6311 13 0.0861 8 0.1159
1990 8 0.4444 173 2.2763 9 0.2308 1 0.125
1991 3 0.1667 199 2.5190 7 0.1556 2 0.2222
1992 320 3.9506 9 0.1875 6 0.6667
1993 1 0.0526 407 4.7326 17 0.3333 3 0.3000
1994 9 0.4737 474 5.1522 9 0.1607 5 0.5000
1995 350 3.8043 21 0.3684 13 1.1818
1996 1 0.0588 359 3.8602 22 0.3385 8 0.8889
1997 3 0.1667 368 3.9149 37 0.5286 4 0.3636
1998 1 0.0556 365 3.7629 36 0.5000 2 0.1818
1999 1 0.0556 319 3.3229 41 0.5190 5 0.4167
2000 410 4.1837 40 0.4762 2 0.1667
2001 411 4.1515 24 0.2824
1990-99 27 0.1406 3334 3.7630 208 0.3574 49 0.4900
1980-2001 46 0.1201 5150 3.0419 285 0.3160 59 0.3057
65
Table 49 Fixed Units (II). UKCS, 1980-2001. No. of accidents and accident frequencies (per unit year). Source: ORION&WOAD
Type of installation
Pumping Injection/riser Accommodation All fixed, (I) & (II)
Year/period N F N F N F N F
1980-89 1 0.0222 7 0.1707 1043 0.9473
1990 1 0.2000 192 1.2468
1991 2 0.3333 213 1.2909
1992 2 0.3333 1 0.1667 338 1.9766
1993 1 0.1250 1 0.1429 430 2.3370
1994 2 0.2500 499 2.5330
1995 384 1.9296
1996 1 0.1111 391 1.9073
1997 1 0.1000 413 1.9299
1998 1 0.1000 405 1.8409
1999 1 0.0909 367 1.6096
2000 1 0.0909 453 1.9277
2001 435 1.8354
1990-99 6 0.0750 8 0.0920 3632 1.8751
1980-2001 7 0.0483 16 0.1067 5563 1.5849
66
8.2 Occurrence frequencies, ORION&WOAD In this section the occurrence frequencies for fixed units in the UKCS in the period 1980-2001 are presented. The following two tables summarise the result of the interrogation of data from “ORION&WOAD”, i.e. the number of occurrences and corresponding frequencies. N denotes number of occurrences and F denotes frequency, i.e. number of occurrences per unit and year (average, 1980-2001). Blank cells denote no occurrences recorded (and hence no frequencies calculated).
Table 50 Fixed Units (I). UKCS, 1980-2001. No. of occurrences and occurrence frequencies (per unit year). Source: ORION&WOAD
Type of installation
Drilling Production Wellhead Compression
Type of event N F N F N F N F
Anchor failure
Blowout 9 5.3•10-3 1 1.1•10-3
Capsize
Collision 17 0.0100 3 3.3E-03
Contact 5 0.0131 153 0.0904 14 0.0155
Crane 16 0.0418 1339 0.7909 34 0.0377 5 0.0259
Explosion 1 2.6•10-3 69 0.0408
Falling object 16 0.0418 1710 1.0100 42 0.0466 9 0.0466
Fire 7 0.0183 729 0.4306 28 0.0310 10 0.0518
Foundering
Grounding
Helicopter 11 6.5•10-3 2 0.0104
Leakage 1 5.9•10-4
List 1 5.9•10-4
Machinery
Off position
Spill/release 13 0.0339 2268 1.3396 192 0.2129 29 0.1503
Structural 14 8.3•10-3
Towing/towline
Well problem 2 5.2•10-3 293 0.1731 10 0.0111
Other 69 0.0408 6 0.0067
67
Table 51 Fixed Units (II). UKCS, 1980-2001. No. of occurrences and occurrence frequencies (per unit year). Source: ORION&WOAD
Type of installation
Pumping Injection/riser Accommodation All fixed, (I) & (II)
Type of event N F N F N F N F
Anchor failure
Blowout 10 2.8•10-3
Capsize
Collision 1 6.7•10-3 21 6.0•10-3
Contact 1 6.9•10-3 4 0.0267 177 0.0504
Crane 1 6.7•10-3 1395 0.3974
Explosion 70 0.0199
Falling object 1 6.9•10-3 2 0.0133 1780 0.5071
Fire 4 0.0276 5 0.0333 783 0.2231
Foundering
Grounding
Helicopter 13 3.7•10-3
Leakage 1 2.8•10-4
List 1 2.8•10-4
Machinery
Off position
Spill/release 3 0.0200 2505 0.7137
Structural 1 6.7•10-3 15 4.3•10-3
Towing/towline
Well problem 305 0.0869
Other 75 0.0214
68
8.2.1 All fixed units In the following tables the number of occurrences and corresponding frequencies for all fixed units are given per year/period. N denotes number of occurrences and F denotes frequency, i.e. number of occurrences per unit and year. Blank cells denote no occurrences recorded (and hence no frequencies calculated).
Table 52 Fixed Units. UKCS, 1980-89, 1990-92. No. of occurrences and occurrence frequencies (per unit year). Source: ORION&WOAD
Year/period
1980-89 1990 1991 1992
Type of event N F N F N F N F
Anchor failure
Blowout 5 4.5E-03
Capsize
Collision 2 1.8E-03 1 0.0054
Contact 80 0.0727 12 0.0779 8 0.0485 5 0.0272
Crane 422 0.3833 63 0.4091 62 0.3758 70 0.3804
Explosion 35 0.0318 4 0.0260 6 0.0364 6 0.0326
Falling object 468 0.4251 68 0.4416 82 0.497 94 0.5109
Fire 228 0.2071 36 0.2338 16 0.097 73 0.3967
Foundering
Grounding
Helicopter 6 5.4•10-3 2 0.0130 1 6.1•10-3
Leakage 1 9.1•10-4
List 1 9.1•10-4
Machinery
Off position
Spill/release 216 0.1962 71 0.4610 75 0.4545 247 1.3424
Structural 4 3.6E-03 1 6.1•10-3
Towing/towline
Well problem 22 0.0200 2 0.0130 2 0.0121 9 0.0489
Other 6 5.4E-03 1 6.5E-03 6 0.0364 4 0.0217
69
Table 53 Fixed Units. UKCS, 1993-1996. No. of occurrences and occurrence frequencies (per unit year). Source: ORION&WOAD
Year
1993 1994 1995 1996
Type of event N F N F N F N F
Anchor failure
Blowout 1 5.1•10-3 3 0.0151 1 4.9•10-3
Capsize
Collision 1 5.8•10-3 3 0.0152 3 0.0151
Contact 7 0.0409 10 0.0508 12 0.0603 10 0.0488
Crane 70 0.4094 94 0.4772 78 0.392 68 0.3317
Explosion 1 5.8•10-3 3 0.0152 1 5.0•10-3 1 4.9•10-3
Falling object 88 0.5146 126 0.6396 101 0.5075 94 0.4585
Fire 48 0.2807 66 0.335 47 0.2362 34 0.1659
Foundering
Grounding
Helicopter 1 5.8•10-3 1 5.0•10-3
Leakage
List
Machinery
Off position
Spill/release 188 1.0994 321 1.6294 217 1.0905 162 0.7902
Structural 4 0.0234 2 0.0101 1 4.9•10-3
Towing/towline
Well problem 2 0.0117 14 0.0711 9 0.0452 50 0.2439
Other 4 0.0234 7 0.0355 8 0.0402 3 0.0146
70
Table 54 Fixed Units. UKCS, 1997-1999. No. of occurrences and occurrence frequencies (per unit year). Source: ORION&WOAD
Year
1997 1998 1999
Type of event N F N F N F
Anchor failure
Blowout
Capsize
Collision 1 4.7•10-3 3 0.0136 3 0.0132
Contact 9 0.0421 5 0.0227 8 0.0351
Crane 93 0.4346 104 0.4727 80 0.3509
Explosion 7 0.0327 1 4.5•10-3 2 8.8•10-3
Falling object 117 0.5467 134 0.6091 126 0.5526
Fire 48 0.2243 44 0.2 41 0.1798
Foundering
Grounding
Helicopter
Leakage
List
Machinery
Off position
Spill/release 200 0.9346 198 0.9 173 0.7588
Structural 1 4.7•10-3 1 4.5•10-3
Towing/towline
Well problem 43 0.2009 44 0.2 38 0.1667
Other 3 0.0140 5 0.0227 5 0.0219
71
Table 55 Fixed Units. UKCS, 2000, 2001, 1990-99, 1980-2001. No. of occurrences and occurrence frequencies (per unit year). Source: ORION&WOAD
Year Period
2000 2001 1990-99 1980-2001
Type of event N F N F N F N F
Anchor failure
Blowout 1 4.2•10-3 5 2.6•10-3 10 2.8•10-3
Capsize
Collision 5 0.0213 15 7.7•10-3 21 6.0•10-3
Contact 8 0.0340 3 0.0127 86 0.0444 177 0.0504
Crane 90 0.3830 100 0.4219 782 0.4037 1395 0.3974
Explosion 3 0.0128 0.0000 32 0.0165 70 0.0199
Falling object 137 0.5830 145 0.6118 1030 0.5318 1780 0.5071
Fire 50 0.2128 52 0.2194 453 0.2339 783 0.2231
Foundering
Grounding
Helicopter 1 4.2•10-3 5 2.6•10-3 13 3.7•10-3
Leakage 1 5.2•10-4 1 2.8•10-4
List 1 5.2•10-4 1 2.8•10-4
Machinery
Off position
Spill/release 217 0.9234 220 0.9283 1852 0.9561 2505 0.7137
Structural 2 8.5•10-3 10 5.2•10-3 15 4.3•10-3
Towing/towline
Well problem 35 0.1489 35 0.1477 213 0.1100 305 0.0869
Other 15 0.0638 5 0.0211 46 0.0237 75 0.0214
8.2.2 Drilling units Since WOAD did not contribute with any recorded accidents to fixed drilling units beyond what was already recorded in the ORION database, the frequencies for the combined ORION & WOAD database remain the same as shown in Table 16 in section 5.3.2 of this report.
72
8.2.3 Production units In the following tables the number of occurrences and corresponding frequencies for fixed production units are given year/period. N denotes number of occurrences and F denotes frequency, i.e. number of occurrences per unit and year. Blank cells denote no occurrences recorded (and hence no frequencies calculated).
Table 56 Production Units. UKCS, 1980-89, 1990, 1991, 1992. No. of occurrences and occurrence frequencies (per unit year). Source: ORION&WOAD
Year/period
1980-89 1990 1991 1992
Type of event N F N F N F N F
Anchor failure
Blowout 5 8.2•10-3
Capsize 0
Collision 2 3.3•10-3 1 0.0123
Contact 73 0.1197 11 0.1447 8 0.1013 4 0.0493
Crane 410 0.6721 53 0.6974 59 0.7468 68 0.8395
Explosion 34 0.0557 4 0.0526 6 0.0759 1 0.0123
Falling object 453 0.7426 57 0.7500 78 0.9873 86 1.0617
Fire 218 0.3574 34 0.4474 14 0.1772 47 0.5802
Foundering
Grounding
Helicopter 5 8.2•10-3 2 0.0263 1 0.0127
Leakage 1 1.6•10-3
List 1 1.6•10-3
Machinery
Off position
Spill/release 205 0.3361 66 0.8684 69 0.873418 176 2.1728
Structural 4 6.6•10-3 1 0.0127 4 0.0494
Towing/towline
Well problem 21 0.0344 2 0.0263 2 0.0253 3 0.0349
Other 6 9.8•10-3 1 0.0132 6 0.0759 4 0.0494
73
Table 57 Production Units. UKCS, 1993-1996. No. of occurrences and occurrence frequencies (per unit year). Source: ORION&WOAD
Year
1993 1994 1995 1996
Type of event N F N F N F N F
Anchor failure
Blowout 1 0.0109 2 0.0217 1 0.0108
Capsize
Collision 1 0.0117 2 0.0217 2 0.0217
Contact 4 0.0466 8 0.0870 11 0.1196 8 0.0860
Crane 67 0.7791 92 1 76 0.8261 65 0.6989
Explosion 6 0.0698 3 0.0326 1 0.0109 1 0.0108
Falling object 91 1.0581 124 1.3478 98 1.0652 88 0.9462
Fire 70 0.8140 60 0.6522 38 0.4130 34 0.3656
Foundering
Grounding
Helicopter 1 0.0109
Leakage
List
Machinery
Off position
Spill/release 231 2.6860 305 3.3152 197 2.1413 147 1.5806
Structural 2 0.0217 1 0.0108
Towing/towline
Well problem 9 0.1047 13 0.1413 7 0.0761 50 0.5376
Other 4 0.0465 7 0.0761 7 0.0761 3 0.0323
74
Table 58 Production Units. UKCS, 1997-1999. No. of occurrences and occurrence frequencies (per unit year). Source: ORION&WOAD
Year
1997 1998 1999
Type of event N F N F N F
Anchor failure
Blowout
Capsize
Collision 1 0.0106 2 0.0206 2 0.0208
Contact 8 0.0851 5 0.0515 5 0.0521
Crane 86 0.9149 100 1.0309 76 0.7917
Explosion 7 0.0745 1 0.0103 2 0.0208
Falling object 107 1.1383 130 1.3402 119 1.2396
Fire 44 0.4681 41 0.4227 35 0.3646
Foundering
Grounding
Helicopter
Leakage
List
Machinery
Off position
Spill/release 173 1.8404 169 1.7423 142 1.4792
Structural 1 0.0106 1 0.0103
Towing/towline
Well problem 43 0.4574 40 0.4124 37 0.3854
Other 3 0.0319 4 0.0412 3 0.0313
75
Table 59 Production Units. UKCS, 2000, 2001, 1990-99, 1980-2001. No. of occurrences and occurrence frequencies (per unit year). Source: ORION&WOAD
Year Period
2000 2001 1990-99 1980-2001
Type of event N F N F N F N F
Anchor failure 0 0
Blowout 1 0.0101 4 4.5•10-3 9 5.3•10-3
Capsize
Collision 4 0.0408 11 0.0124 17 0.0100
Contact 6 0.0612 2 0.0202 72 0.0813 153 0.0904
Crane 89 0.9082 98 0.9899 742 0.8375 1339 0.7909
Explosion 3 0.0306 32 0.0361 69 0.0408
Falling object 136 1.3878 143 1.4444 978 1.1038 1710 1.0100
Fire 49 0.5000 45 0.4545 417 0.4707 729 0.4306
Foundering
Grounding
Helicopter 1 0.0101 4 4.5•10-3 11 6.5•10-3
Leakage 1 5.9•10-4
List 1 5.9•10-4
Machinery
Off position
Spill/release 181 1.8469 207 2.0909 1675 1.8905 2268 1.3396
Structural 2 0.0204 10 0.0113 14 8.3•10-3
Towing/towline
Well problem 33 0.3367 32 0.3232 206 0.2325 293 0.1731
Other 13 0.1327 5 0.0505 42 0.0474 69 0.0408
76
8.2.4 Wellhead units In the following tables the number of occurrences and corresponding frequencies for fixed wellhead (production) units are given per year/period. N denotes number of occurrences and F denotes frequency, i.e. number of occurrences per unit and year. Blank cells denote no occurrences recorded (and hence no frequencies calculated).
Table 60 Wellhead Units. UKCS, 1980-89, 1990, 1991, 1992. No. of occurrences and occurrence frequencies (per unit year). Source: ORION&WOAD
Year/period
1980-89 1990 1991 1992
Type of event N F N F N F N F
Anchor failure
Blowout 1 6.6•10-3
Capsize
Collision
Contact 1 6.6•10-3 1 0.0256 0 1 0.0208
Crane 3 0.0199 5 0.1282 2 0.0444 1 0.0208
Explosion 3 3.4•10-3 8 5.3•10-3
Falling object 4 0.0265 7 0.1795 3 0.0667 1 0.0208
Fire 4 0.0265
Foundering
Grounding
Helicopter
Leakage
List
Machinery
Off position
Spill/release 4 0.0265 3 0.0769 5 0.1111 7 0.1458
Structural
Towing/towline
Well problem 1 6.6•10-3
Other
77
Table 61 Wellhead Units. UKCS, 1993-1996. No. of occurrences and occurrence frequencies (per unit year). Source: ORION&WOAD
Year
1993 1994 1995 1996
Type of event N F N F N F N F
Anchor failure
Blowout
Capsize
Collision 1 0.0175
Contact 1 0.0179 1 0.0175 2 0.0308
Crane 3 0.0589 1 0.0179 1 0.0175 3 0.0462
Explosion
Falling object 3 0.0589 1 0.0179 1 0.0175 5 0.0769
Fire 1 0.0196 2 0.0357 3 0.0526
Foundering
Grounding
Helicopter
Leakage
List
Machinery
Off position
Spill/release 13 0.2549 7 0.125 14 0.2456 15 0.2308
Structural
Towing/towline
Well problem
Other 1 0.0175
78
Table 62 Wellhead Units. UKCS, 1997-1999. No. of occurrences and occurrence frequencies (per unit year). Source: ORION&WOAD
Year
1997 1998 1999
Type of event N F N F N F
Anchor failure
Blowout
Capsize
Collision 1 0.0139 1 0.0127
Contact 1 0.0142 3 0.0380
Crane 6 0.0857 3 0.0417 3 0.0380
Explosion
Falling object 6 0.0857 3 0.0417 5 0.0633
Fire 3 0.0429 3 0.0417 4 0.0506
Foundering
Grounding
Helicopter
Leakage
List
Machinery
Off position
Spill/release 25 0.3571 26 0.3611 26 0.3291
Structural
Towing/towline
Well problem 3 0.0417 1 0.0127
Other 1 0.0139 2 0.0253
79
Table 63 Wellhead Units. UKCS, 2000, 2001, 1990-99, 1980-2001. No. of occurrences and occurrence frequencies (per unit year). Source: ORION&WOAD
Year Period
2000 2001 1990-99 1980-2001
Type of event N F N F N F N F
Anchor failure
Blowout 1 1.1•10-3
Capsize
Collision 3 5.2•10-3 3 3.3•10-3
Contact 2 0.0238 1 0.0118 10 0.0172 14 0.0155
Crane 1 0.0119 2 0.0235 28 0.0481 34 0.0377
Explosion
Falling object 1 0.0119 2 0.0235 35 0.0601 42 0.0466
Fire 1 0.0119 7 0.0824 16 0.0275 28 0.0310
Foundering
Grounding
Helicopter
Leakage
List
Machinery
Off position
Spill/release 34 0.4048 13 0.1529 141 0.2423 192 0.2129
Structural
Towing/towline
Well problem 2 0.0238 3 0.0353 4 6.9•10-3 10 0.0111
Other 2 0.0238 4 6.9•10-3 6 0.0067
80
8.2.5 Compression units In the following tables the number of occurrences and corresponding frequencies for fixed wellhead units are given per year/period. N denotes number of occurrences and F denotes frequency, i.e. number of occurrences per unit and year. Blank cells denote no occurrences recorded (and hence no frequencies calculated).
Table 64 Compression Units. UKCS, 1980-89, 1990, 1991, 1992. No. of occurrences and occurrence frequencies (per unit year). Source: ORION&WOAD
Year/period
1980-89 1990 1991 1992
Type of event N F N F N F N F
Anchor failure
Blowout
Capsize
Collision
Contact
Crane 2 0.0290 1 0.1111
Explosion
Falling object 3 0.0435 1 0.1250 1 0.1111
Fire 1 0.0145 1 0.1111
Foundering
Grounding
Helicopter 2 0.0290
Leakage
List
Machinery
Off position
Spill/release 1 0.0145 1 0.1111 2 0.2222
Structural
Towing/towline
Well problem
Other
81
Table 65 Compression Units. UKCS, 1993-1996. No. of occurrences and occurrence frequencies (per unit year). Source: ORION&WOAD
Year
1993 1994 1995 1996
Type of event N F N F N F N F
Anchor failure
Blowout
Capsize
Collision
Contact
Crane 1 0.1000 1000 0.0909
Explosion
Falling object 1 0.1000 2 0.1818
Fire 1 0.1000 6 0.5455
Foundering
Grounding
Helicopter
Leakage
List
Machinery
Off position
Spill/release 5 0.5000 4 0.4000 6 0.5455
Structural
Towing/towline
Well problem
Other
82
Table 66 Compression Units. UKCS, 1997-1999. No. of occurrences and occurrence frequencies (per unit year). Source: ORION&WOAD
Year
1997 1998 1999
Type of event N F N F N F
Anchor failure
Blowout
Capsize
Collision
Contact
Crane
Explosion
Falling object 1 0.0909
Fire 1 0.0833
Foundering
Grounding
Helicopter
Leakage
List
Machinery
Off position
Spill/release 2 0.1818 2 0.1818 4 0.3333
Structural
Towing/towline
Well problem
Other
83
Table 67 Compression Units. UKCS, 2000, 2001, 1990-99, 1980-2001. No. of occurrences and occurrence frequencies (per unit year). Source: ORION&WOAD
Year Period
2000 2001 1990-99 1980-2001
Type of event N F N F N F N F
Anchor failure
Blowout
Capsize
Collision
Contact
Crane 3 0.0300 5 0.0259
Explosion
Falling object 6 0.0600 9 0.0466
Fire 9 0.0900 10 0.0518
Foundering
Grounding
Helicopter 2 0.0104
Leakage
List
Machinery
Off position
Spill/release 2 0.1667 26 0.2600 29 0.1503
Structural
Towing/towline
Well problem
Other
8.2.6 Pumping units No accidents are recorded on fixed pumping platforms in either the WOAD database or the ORION database in the period 1980-2001, and hence the overall calculated occurrence frequency is 0.
8.2.7 Injection/riser units Since WOAD did not contribute with any recorded accidents to fixed injection/riser units beyond what was already recorded in the ORION database, the frequencies for the combined ORION & WOAD database remain the same as shown in Table 29 in section 5.3.7 of this report.
8.2.8 Accommodation units The recorded number and type of occurrences and the corresponding frequencies are given in the following table. N denotes number of occurrences and F denotes frequency, i.e. number of occurrences per unit and year.
84
Table 68 Accommodation units. UKCS. 1980-2001. No. of occurrences per unit year. Source: ORION&WOAD
Year Type of event N F
Average 1980-89
Contact 2 0.0488
Crane 1 0.0244
Falling object 1 0.0244
Fire 2 0.0488
Spill/release 1 0.0244
Structural 1 0.0244
1992 Contact 1 0.1429
1993 Fire 1 0.125
1994 Contact 1 0.1111
Spill/release 1 0.1111
1996 Fire 1 0.1000
1997 Fire 1 0.1000
1998 Spill/release 1 0.0909
1999 Falling object 1 0.0909
2000 Collision 1 0.0909
Average 1990-99
Contact 2 0.0230
Falling object 1 0.0115
Fire 2 0.0230
Spill/release 2 0.0230
Average 19802001
Collision 1 6.7•10-3
Contact 4 0.0267
Crane 1 6.7•10-3
Falling object 2 0.0133
Fire 5 0.0333
Spill/release 3 0.0200
85
8.3 Frequencies, fixed units on NCS An interrogation of the WOAD database for accidents and incidents on fixed production units on the Norwegian Continental Shelf (NCS) in the period 1980-2001, showed a total of 1350 recorded accidents. Combined with the corresponding exposure of about 700 unit-years in the same period, the frequency becomes 1.93 accidents per unit-year.
The comparable figure for the UKCS, as calculated in this report using the combined ORION and WOAD databases, is 1.58 (from Table 49).
86
9 CONCLUSIONS The conclusions from the work undertaken in this project are summarised below.
• The event frequencies strongly vary with the source being used
As identified in the recent project on floating units (ref. /1/), this project also clearly shows that the event frequencies being obtained strongly depend on which database is being interrogated.
• The main source for accident and incident information being available for the UKCS offshore industry should be the HSE’s ORION database
Due to the accident reporting requirements for fixed units on the UK Continental Shelf (UKCS), the main source for accident and incident information being available for the UKCS offshore industry should be the HSE’s ORION database. The interrogation of ORION in this project showed that the database contains information for accidents and incidents ranging from hazardous situations and working accidents with no consequences to severe damage and total loss of units.
• Large difference in number of accidents between WOAD and ORION
When comparing the information held by DNV’s Worldwide Offshore Accident Databank (WOAD) and ORION, there is a big difference in number of accidents. This is mainly explained by the fact that WOAD only receives information about accidents through publicly available sources, which in most cases only addresses events with large consequences.
• Slight increase in event frequencies when merging the databases together
If all fixed units are considered for the period 1980-2001, this study demonstrates a total event frequency of 1.58 per installation per year. Only a slight increase in the frequency is seen when merging the ORION and WOAD databases together. This is due to that there are only a few (51 to be exact) events being recorded in WOAD and not in ORION. The total event frequency is a factor about 35 times higher than that which is obtained from WOAD.
87
88
10 REFERENCES
/1/ “Accident Statistics for Floating Offshore Units on the UK Continental Shelf in 198098”. HSE Offshore Technology Report – OTO 2000/091.
/2/ “Accident Statistics for Fixed Offshore Units on the UK Continental Shelf in 1991-99”. HSE Offshore Technology Report – OTO 2002/012.
/3/ “The North Sea Development Guide”. Seventh Edition, Oilfield Publications Limited. ISBN 1 902157 08 7, November 1998.
89
90
APPENDIXA
HSE ORION; DANGEROUS OCCURRENCE TYPE CODES
A-1
The following codes are used for the parameter Dangerous occurrence type given in HSE’s ORION Database. This field is only completed for category 4 incidents (“Dangerous Occurrences”) and only for incidents in the period from April 1996 to date (ref. RIDDOR 95).
Code Short text / Output Name Description
01 FAIL LIFT MACH The collapse of the overturning of, or the failure of any load bearing part of any
a. lift or hoist; b. crane or derrick; c. mobile powered access platform; d. access cradle or window-cleaning cradle; e. pile-driving or rig having an overall height. when operating, of
more than 7 metres, or f. fork lift truck.
02 FAIL VESSEL The failure of any closed vessel (including a boiler or boiler tube) or of any associated pipework, in which the internal pressure was above or below atmospheric pressure, where the failure has the potential to cause the death of any person.
03 FAIL FREIGHT 1. The failure of any freight container in any of its load-bearing parts while it is being raised, lowered or suspended,
2. In this paragraph, "freight container" means a container as defined in regulation 2(1) of the Freight Containers (Safety Convention) Regulations 1984(a).
04 CONTACT ELECTRIC Any unintentional incident in which plant or equipment either
a. comes into contact with an uninsulated overhead electric line in which the voltage exceeds 200 volts; or
b. causes an electrical discharge from such an electric line by coming into close proximity to it.
05 FIRE/EX ELECTRIC Electrical short circuit or overload attended by fire or explosion which results in the stoppage of the plant involved for more than 24 hours or which has the potential to cause the death of any person.
06 EXPLOSION/MISFIRE Any of the following incidents involving explosives:
a. the unintentional explosion or ignition of explosives other than one i. caused by the unintentional discharge of a weapon
where, apart from that unintentional discharge, the weapon and explosives functioned as they were designed to do; or
ii. where a fail-safe device or safe system of work functioned so as to prevent any person from being injured in consequence of the explosion or ignition;
b. a misfire (other than one at a mine or quarry or inside a well or one involving a weapon) except where a fail-safe device or safe system of work functioned so as to prevent any person from being endangered in consequence of the misfire;
c. the failure of the shots in any demolition operation to cause the intended extent of collapse or direction of fall of a building or structure;
d. the projection of material (other than at a quarry) beyond the boundary of the site on which the explosives are being used or beyond the danger zone in circumstances such that any person was or might have been injured thereby;
e. any injury to a person (other than at a mine or quarry or one otherwise reportable under these Regulations) involving first-aid or medical treatment resulting from the explosion or discharge of any explosives or detonator.
A-2
Code Short text / Output Name Description
07 RELEASE SUBS Any accident or incident which resulted or could have resulted in the release or escape of a biological agent likely to cause severe human infection or illness.
08 FAIL RADIATION 1. any incident in which
a. the malfunction of a radiation generator or its ancillary equipment used in fixed or mobile industrial radiography, the irradiation of food or the processing of products by irradiation, causes it to fail to de-energise at the end of the intended exposure period ; or
b. the malfunction of equipment used in fixed or mobile industrial radiography or gamma irradiation causes a radioactive source to fail to return to its safe position by the normal means at the end of the intended exposure period,
2. In this paragraph, "radiation generator" has the same meaning as in regulation 2 of the Ionising Radiations Regulations 1985(b).
09 FAIL BREATHING 1. Any incident in which breathing apparatus malfunctions
a. while in use. or
b. during testing immediately prior to use in such a way that had the malfunction occurred while the apparatus was in use it would have posed a danger to the health or safety of the user,
2. This paragraph shall not apply to breathing apparatus while it is being -
a. used in a mine; or
b. maintained or tested as part of a routine maintenance procedure.
10 FAIL DIVING Any of the following incidents in relation to a diving operation
a. the failure or the endangering of
i. any lifting equipment associated with the diving operation, or
ii. life support equipment, including control panels, hoses and breathing apparatus, which puts a diver at risk;
b. any damage to, or endangering of, the dive platform, or any failure of the dive platform to remain on station, which puts a diver at risk;
c. the trapping of a diver;
d. any explosion in the vicinity of a diver; or
e. any uncontrolled ascent or any omitted decompression which puts a diver at risk.
11 COLLAPSE SCAFF The collapse or partial collapse of
a. any scaffold which is
i. more than 5 metres in height which results in a substantial part of the scaffold falling or overturning; or
ii. erected over or adjacent to water in circumstances such that there would be a risk of drowning to a person falling from the scaffold into the water; or
b. the suspension arrangements (including any outrigger) of any slung or suspended scaffold which causes a working platform or cradle to fall.
A-3
Code Short text / Output Name Description
12 CRASH TRAIN
13 FAIL WELL Any of the following incidents in relation to a well (other than a well sunk for the purposes of the abstraction of water)
a. a blow-out (that is to say an uncontrolled flow of well-fluids from a well);
b. the coming into operation of a blow-out prevention or diversion system to control a flow from a well where normal control procedures fail;
c. the detection of hydrogen sulphide in the course of operations at a well or in samples of well-fluids from a well where the presence of hydrogen sulphide in the reservoir being drawn on by the well was not anticipated by the responsible person before that detection;
d. the taking of precautionary measures additional to any contained in the original drilling programme following failure to maintain a planned minimum separation distance between wells drilled from a particular installation; or
e. the mechanical failure of any safety critical element of a well (and for this purpose the safety critical element of a well is any part of a well whose failure would cause or contribute to. or whose purpose is to prevent or limit the effect of, the unintentional release of fluids from a well or a reservoir being drawn on by a well).
14 FAIL PIPELINE The following incidents in respect of a pipeline or pipeline works
a. the uncontrolled or accidental escape of anything from. or inrush of anything into, a pipeline which has the potential to cause the death of, major injury or damage to the health of any person or which results in the pipeline being shut down for more than 24 hours;
b. the unintentional ignition of anything in a pipeline or of anything which, immediately before it was ignited, was in a pipeline;
c. any damage to any part of a pipeline which has the potential to cause the death of, major injury or damage to the health of any person or which results in the pipeline being shut down for more than 24 hours;
d. any substantial and unintentional change in the position of a pipeline requiring immediate attention to safeguard the integrity or safety of a pipeline;
e. any unintentional change in the subsoil or seabed in the vicinity of a pipeline which has the potential to affect the integrity or safety of a pipeline;
f. any failure of any pipeline isolation device, equipment or system which has the potential to cause the death of, major injury or damage to the health of any person or which results in the pipeline being shut down for more than 24 hours; or
g. any failure of equipment involved with pipeline works which has the potential to cause the death of, major injury or damage to the health of any person.
15 FAIL FAIR RIDE
A-4
Code Short text / Output Name Description
16 OVERTURN DANGSUB 1. Any incident involving a road tanker or tank container used for the carriage of a dangerous substance in which
a. the road tanker or vehicle carrying the tank container overturns (including turning onto its side);
b. the tank carrying the dangerous substance is seriously damaged;
c. there is an uncontrolled release or escape of the dangerous substance being carried or;
d. there is a fire involving the dangerous substance being carried.
2. In this paragraph "carriage", "dangerous substance", "road tanker" and "tank container" have the same meanings as in regulation 2(1) of the Road Traffic (Carriage of Dangerous Substances in Road Tankers and Tank Containers) Regulations 1992(a).
17 RELEASE DANGSUB 1. (Any incident involving a vehicle used for the carriage of a dangerous substance, other than a vehicle to which paragraph 16 applies, where there is
a. an uncontrolled release or escape of the dangerous substance being carried in such a quantity as to have the potential to cause the death of, or major injury to, any person; or
b. a fire which involves the dangerous substance being carried,
2. In this paragraph, "carriage" and "dangerous substance" have the same meaning as in regulation 2(1) of the Road Traffic (Carriage of Dangerous Substance in Packages etc) Regulations 1992(b).
73 RELEASE PET HYDRO Any unintentional release of petroleum hydrocarbon on or from an offshore installation which
a. results in
i. a fire or explosion; or
ii. the taking of action to prevent or limit the consequences of a potential fire or explosion; or
b. has the potential to cause death or major injury to any person.
74 FIRE OFFSHORE Any fire or explosion at an offshore installation, other than one to which paragraph 73 above applies, which results in the stoppage of plant or the suspension of normal work.
75 RELEASE OFFSHORE The uncontrolled or unintentional release or escape of any substance (other than petroleum hydrocarbon) on or from an offshore installation which has the potential to cause the death or, major injury to or damage to the health of any person.
76 COLLAPSE OFFSHORE Any unintended collapse of any offshore installation or any unintended collapse of any part thereof or any plant thereon which jeopardises the overall structural integrity of the installation.
A-5
Code Short text / Output Name Description
77 FAILURE OFFSHORE Any of the following occurrences having the potential to cause death or major injury
a. the failure of equipment required to maintain a floating offshore installation on station;
b. the dropping of any object on an offshore installation or on an attendant vessel or into the water adjacent to an installation or vessel; or
c. damage to or on an offshore installation caused by adverse weather conditions.
78 COLLISION OFFSHORE Any collision between a vessel or aircraft and an offshore installation which results in damage to the installation, the vessel or the aircraft.
79 POSS COLLISION OFFSHORE
Any occurrence with the potential for a collision between a vessel and an offshore installation where. had a collision occurred, it would have been liable to jeopardise the overall structural integrity of the offshore installation.
80 COLLAPSE SEABED Any subsidence or local collapse of the seabed likely to affect the foundations of an offshore installation or the overall structural integrity of an offshore installation.
81 LOSS OF BUYANCY Any incident involving loss or stability or buoyancy of a floating offshore installation.
82 EVACUATE OFFSHORE Any evacuation (other than one arising out of an incident reportable under any other provision of these Regulations) of an offshore installation, in whole or part, in the interests of safety.
83 FALL OFFSHORE Any case of a person falling more than 2 metres (6.56 ft) into water (unless the fall results in death or injury required to be reported under sub-paragraphs (a) - (d) or regulation 3(1)).
Printed and published by the Health and Safety Executive C1.25 06/03
ISBN 0-7176-2211-8
RR 096
78071 7 6221 1 5£15.00 9
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