Offshore Fixed Rig Risk

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]

ii

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

iii

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.

iv

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

1

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.

2

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

3

Table 2 Fixed Units (II). UKCS, 1980-2001. No. of accidents and accident frequencies (per unit year). Source: ORION&WOAD


Pumping Injection/riser Accommodation All fixed, (I) & (II)


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.

4

• 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.

5

6

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.

7

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

9

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”

10

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

11

Table 4 Fixed Units (II). UKCS. 1980-2001. Number of unit-years


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

12

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).

13

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).

14

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

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

15

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

16

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.

17

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.

18

Table 6 Fixed Units (I). UKCS. 1980-2001. No. of accidents. Source: ORION


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


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 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 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



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


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


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


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


Fire 1 0.0556


1991 Contact 1 0.0556

Crane 1 0.0556


1993 Spill/release 1 0.0526

1994 Crane 1 0.0526


Fire 3 0.1579


Well problem 1 0.0526

1996 Falling object 1 0.0588

1997 Crane 1 0.0556


1998 Crane 1 0.0556



1999 Crane 1 0.0556



Average 1990-99

Contact 1 5.5•10-3

Crane 10 0.0549


Fire 4 0.0220



Average 1980-2001

Contact 5 0.0131

Crane 16 0.0418

Explosion 1 2.6•10-3


Fire 7 0.0183


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


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


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


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


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


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


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


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


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


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


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


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


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


Anchor failure

Blowout

Capsize

Collision

Contact

Crane

Explosion


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


Anchor failure

Blowout

Capsize

Collision

Contact

Crane 3 0.0300 5 0.0259

Explosion


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


Average 1980-89


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


Average 1980-89

Contact 2 0.0488

Crane 1 0.0244


Fire 2 0.0488


1992 Contact 1 0.1429

1993 Fire 1 0.1250

1994 Contact 1 0.1111


1996 Fire 1 0.1000

1997 Fire 1 0.1000



2000 Collision 1 0.0909

Average 1990-99

Contact 2 0.0230


Fire 2 0.0230


Average 19802001

Collision 1 6.7•10-3

Contact 4 0.0267

Crane 1 6.7•10-3


Fire 5 0.0333


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



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


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 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 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



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


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


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


Anchor failure

Blowout 3 2.7•10-3

Capsize


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


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


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


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


Anchor failure

Blowout

Capsize


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


Towing/towline


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


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


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


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


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


Anchor failure

Blowout

Capsize

Collision 1 0.0103

Contact

Crane 1 0.0106

Explosion


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


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


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


Average 1980-89

Blowout 1 6.6•10-3



1995 Collision 1 0.0175

Average 1990-99


Average 19802001

Blowout 1 1.1•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


Average 1980-89

Fire 1 0.0145

Helicopter 1 0.0145


Average 19802001

Fire 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


Average 1980-89

Fire 1 0.0244

Structural 1 0.0244

Average 19802001

Fire 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




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




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




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


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




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


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


Other 75 0.0214

68


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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


Anchor failure

Blowout

Capsize

Collision

Contact

Crane 1 0.1000 1000 0.0909

Explosion


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


Anchor failure

Blowout

Capsize

Collision

Contact

Crane

Explosion


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


Anchor failure

Blowout

Capsize

Collision

Contact

Crane 3 0.0300 5 0.0259

Explosion


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


Average 1980-89

Contact 2 0.0488

Crane 1 0.0244


Fire 2 0.0488


Structural 1 0.0244

1992 Contact 1 0.1429

1993 Fire 1 0.125

1994 Contact 1 0.1111


1996 Fire 1 0.1000

1997 Fire 1 0.1000



2000 Collision 1 0.0909

Average 1990-99

Contact 2 0.0230


Fire 2 0.0230


Average 19802001


Contact 4 0.0267

Crane 1 6.7•10-3


Fire 5 0.0333


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


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


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


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


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

Accid

ent sta

tistics for fixe

d o

ffshore

units o

n th

e U

K C

ontin

enta

l Shelf 1

980 - 2

001

HS

E B

OO

KS

Documents

Offshore Fixed Rig Risk