SPC/Enforcement/89
The Gas Safety (Management) Regulations 1996 (GSMR) require gas conveyors to investigate gas escapes that have, or are likely to have, resulted in a fire or explosion and submit an investigation report to HSE. This guidance aims to assist the understanding of all parties.
1. Regulations 7 (12) and 7(13) of GSMR place duties on gas conveyors to investigate gas escapes that have, or are likely to have, resulted in a fire or explosion. Regulation 7(16) goes on to require conveyors to prepare an investigation report and submit it to HSE as soon as is reasonably practicable after the investigation has been completed.
2. This SPC addresses the content and scope of GSMR investigation reports. It is in two parts:
3. This SPC does not deal with the technical aspects of site investigation or with investigations into incidents of carbon monoxide poisoning. Advice on the latter should be sought from the relevant FOD team.
4. As well as being necessary to comply with legal requirements, accident and incident investigation provides an opportunity for the dutyholder to check their performance. They can learn from mistakes and improve their health and safety management system and control of risks. Arrangements for incident investigation should be formalised and summarised in the gas conveyor's GSMR safety case. Issues to consider include the following.
5. Conveyors should have a clear policy setting out the organisation and arrangements for incident investigations. This should detail how they will meet the commitment contained in their safety case to investigate incidents and accidents (paragraph 58 of HSE publication L80 refers). The policy and arrangements should dovetail with other parts of the organisation's health and safety management system.
6. An investigation will only succeed if it is carried out in a structured way with clear objectives which are understood by those carrying it out. It should establish both the immediate and underlying cause(s) and deliver conclusions consistent with the evidence. It should provide the basis for determining the level of risk - i.e. deciding on the likelihood of recurrence and the possible consequences - and allow emerging trends to be identified. Finally, it should enable suitable controls to be introduced to minimise or eliminate the root causes, where possible, and prevent further incidents.
7. Not all events need to be investigated to the same depth, the scale of the investigation should be proportionate to the incident. Organisations should have a system to classify and categorise incidents which should be based not only on the actual outcome, but also the potential of the incident. For minor incidents with low risk potential, it may be sufficient for the investigation to be carried out by supervisors. A major incident involving death, injury or a major system failure may require a senior manager to lead a full and detailed investigation. This could also include support from an independent organisation.
8. Investigations should be carried out by personnel at the appropriate level and with the necessary expertise. Incident investigation is specialised work, therefore conveyors should ensure that investigations are only carried out by people with the right skills, knowledge and expertise. NB Competence is not necessarily vested in one person alone so the more complex an investigation, the more people and disciplines may need to be involved.
9. Where possible, particularly in more serious cases, reports should be reviewed by an independent senior manager or safety adviser not directly involved with the investigation. Their role should be to monitor the quality of investigations and ensure appropriate conclusions are being reached. They should have sufficient status and knowledge to make authoritative recommendations.
10. Just as the scale and nature of the investigation will depend on the incident, so too will the report. However, the guidance to regulation 7(16) of GSMR identifies the following three main areas which should be covered by all reports.
11. This will be largely factual and, in the case of simple investigations, may be brief. Possible headings include:
12. For more complex incidents, a chronology or sequence of events log may be appropriate. This will allow significant factors or events to be identified.
13. Accidents and incidents rarely arise from a single cause and there are often underlying failures in the management system itself which have helped create the circumstances leading to the event. Good investigations identify both immediate and underlying causes, including human factors (see HSE publication HS(G)48 'Reducing Error and Influencing Behaviour' and the human factors in accident investigations pages of the HSE website).
14. Immediate causes include the job being done and the people involved. These are often relatively easy to identify. Underlying causes can be less tangible. In essence, they are the management and organisational factors which explain why an event occurred. HSE publication HS(G)65 'Successful Health and Safety Management' suggests an approach to analysing the immediate and underlying causes of events. This may be a useful basis for designing an approach that fits the needs of the organisation.
15. For example, the immediate cause of an incident may have been an employee's failure to follow procedures / safe system of work. However, there may be a number of underlying factors that allowed this to happen, such as lack of competence, custom and practice, inappropriate or inadequate procedures etc. Failure to consider the underlying causes frequently leads only to the employee being blamed. This discourages an open culture and prevents an organisation learning wider lessons and improving its performance.
16. In complex investigations, conveyors may wish to use more advanced techniques to identify underlying causes, such as Failure Modes Effects Analysis, Management Oversight Risk Trees (MORT), Fault and Event Tree Analysis, and Events and Causal Factors Analysis.
17. Investigation reports should reflect the circumstances and be consistent with the available evidence. Remedial actions and recommendations should be prioritised and responsibilities allocated. The report should also identify, where appropriate, how actions will be monitored and audited.
18. SPC/Admin/40 'Reporting and Processing of Certain Gas Incidents under RIDDOR and GSMR' gives further information on the submission of GSMR investigation reports. Reports should be sent by email to: GSMR@hse.gsi.gov.uk.
19. For further information contact the Gas and Pipelines Unit, National Inspection and Operational Support Team (HID SI3D) in Sheffield.
