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Control of major accident hazards Regulations 1999 (COMAH)

Background notes and brief guidance for operators

Introduction

The COMAH Regulations implement the Seveso II Directive except for the land-use planning requirements which are implemented by changes to planning legislation. They replaced the Control of Industrial Major Accident Hazards Regulations 1984 (CIMAH) and came into force on 1st April 1999. The Regulations are amended from 30 June 2005 to reflect changes to Seveso II. This brief guide outlines the main duties and explains what you need to do if the Regulations apply to you.

Information on various aspects of the COMAH regime is also available on the following web sites:

What is the main aim of the COMAH Regulations?

Their main aim is to prevent and mitigate the effects of those major accidents involving dangerous substances, such as chlorine, liquefied petroleum gas, explosives and arsenic pentoxide which can cause serious damage/harm to people and/or the environment. The COMAH Regulations treat risks to the environment as seriously as those to people.

What changes did the 2005 Amendment Regulations introduce?

The main effect of the COMAH (Amendment) Regulations is to broaden the scope COMAH through changes to Parts 2 and 3 of Schedule 1. These include:

Other changes include the notification requirements for petroleum products, the review and revision of safety reports, a small number of changes to Schedule 4 Part 2 (minimum information to be provided in a safety report), and the provision of an amended safety report if information is excluded from the public register.

A summary of the changes is available, together with information about timescales for compliance.

Who enforces COMAH?

The COMAH Regulations are enforced by a competent authority (CA) consisting of:

The CA operates to a Memorandum of Understanding which sets out the arrangements for joint working.

The Regulations place duties on the CA to inspect activities subject to COMAH and prohibit the operation of an establishment if there is evidence that measures taken for prevention and mitigation of major accidents are seriously deficient. It also has to examine safety reports and inform operators about the conclusions of its examinations within a reasonable time period.

Charging

The CA charges for work it undertakes on COMAH. Charges are made on an actuals basis i.e. the recovery of the full costs of the time spent by the CA in carrying out COMAH-related activities for a particular establishment.

A charging review group has been set up to discuss the operation of the financial and administrative arrangements of the charging regime.

For further information see:

Who is affected?

Mainly the chemical industry, but also some storage activities, explosives and nuclear sites and other industries, where threshold quantities of dangerous substances identified in the Regulations are kept or used.

The substances which cause the duties to apply are detailed in Schedule 1 of the Regulations as are the quantities which set the two thresholds for application.

Operators of sites that hold larger quantities of dangerous substances ('top tier' sites) are subject to more onerous requirements than those of 'lower tier' sites.

What do you need to do?

Firstly you need to determine if the Regulations apply to you. Regulation 3, together with Schedule 1, will provide the answer. If you have enough dangerous substances present to take you over the lower threshold then the lower-tier duties apply and if you have enough to exceed the higher threshold then the top-tier duties apply.

Key duties for operators

Lower-tier sites

Notify basic details to the CA
Operators of all establishments subject to the Regulations must notify certain basic details to the CA. The key points which have to be included in the notification are given below but full details are given in Schedule 3 to the Regulations.
  • name and address of operator
  • address of establishment
  • name or position of person in charge
  • details of dangerous substances on site (a breakdown is required for petroleum products)
  • site activities
  • environmental details
When?
From 30 June 2005, operators who come into scope of the Regulations because of an increase in the quantity of dangerous substances present must submit a notification before the start of construction and/or operation. Operators who come into scope for other reasons e.g. a change in classification or qualifying quantity of a substance in Schedule 1 or a change in knowledge about dangerous substances generated during loss of control of an industrial chemical process should submit a notification within three months.
Take all measures necessary to prevent major accidents and limit their consequences to people and the environment
This is the general duty on all operators and underpins all the regulations. It is a high standard and applies to all establishments within scope. By requiring measures both for prevention and mitigation there is a recognition that all risks cannot be completely eliminated. This in turn implies that proportionality must remain a key element in the enforcement policy of the HSE and the Agencies. Thus, the phrase "all measures necessary" will be interpreted to include this principle and a judgment will be made about the measures in place. Where hazards are high then high standards will be required to ensure risks are acceptably low, in line with the HSE's and Agencies' policy that enforcement should be proportionate. Prevention should be based on the principle of reducing risk to a level as low as is reasonably practicable (ALARP) for human risks and using the best available technology not entailing excessive cost (BATNEEC) for environmental risks. The ideal should always be, wherever possible, to avoid a hazard altogether.
Prepare a major accident prevention policy
Regulation 5 requires lower-tier operators to prepare a document setting out their policy for preventing major accidents (a major accident prevention policy or MAPP).

The MAPP will usually be a short and simple document setting down what is to be achieved but it should also include a summary and further references to the safety management system that will be used to put the policy into action. The detail will be contained in other documentation relating to the establishment e.g. plant operating procedures, training records, job descriptions, audit reports, to which the MAPP can refer.

The MAPP also has to address issues relating to the safety management system. The details are given in Schedule 2 of the Regulations but the key areas are:

  • organisation and personnel
  • identification and evaluation of major hazards
  • operational control
  • planning for emergencies
  • monitoring, audit and review.
When?
From 30 June 2005 operators who come into scope of the Regulations must prepare their MAPP without delay, but within three months of becoming subject to COMAH.

Top-tier operators

Top-tier operators have to comply with the above requirement for a MAPP except that they do not have to prepare a separate document - their safety reports (see below) have to include the information that lower-tier operators provide in their MAPPs. They also have the following additional duties:

Prepare a safety report
A safety report is a document prepared by the site operator and provides information to demonstrate to the CA that all measures necessary for the prevention and mitigation of major accidents have been taken. The purposes and contents of a safety report are set out in Schedule 4 to the Regulations.

The safety report must include:

  • a policy on how to prevent and mitigate major accidents;
  • a management system for implementing that policy;
  • an effective method for identifying any major accidents that might occur;
  • measures (such as safe plant and safe operating procedures) to prevent and mitigate major accidents;
  • information on the safety precautions built into the plant and equipment when it was designed and constructed;
  • details of measures (such as fire-fighting, relief systems and filters) to limit the consequences of any major accident that might occur; and
  • information about the emergency plan for the site, which is also used by the local authority in drawing up an off-site emergency plan.

Safety reports will be available to the public via the CA registers, subject to safeguards for national security, commercial and personal confidentiality.

When?
The dates for submission of safety reports are set out in regulation 7 but are given here for information:

Operators of completely new establishments (so called green field sites) have to provide some information before construction commences and complete the safety report before operation begins.

Operators whose establishments become COMAH top-tier after 30 June 2005 must submit their safety report as follows:

  • before operation starts, if the change arises from an increase in the quantity of dangerous substances; or
  • within one year of the requirement applying, if a report is needed because of other changes e.g. a change in classification of qualifying quantity of a substance in Schedule 1 or a change in knowledge about dangerous substances generated during loss of control of an industrial chemical process.
Update the safety report after significant changes or new knowledge about safety matters or every five years
The safety report needs to be kept up to date. If there are any modifications to the plant or the way it is operated or if new facts or information become available, the safety report must be reviewed and, if necessary, revised at the time. It must be reviewed after five years even if there have not been any changes. The operator must notify the CA of any revision, and also if the five-year review does not lead to a revision.
Prepare and test an on-site emergency plan
Top-tier operators must prepare an emergency plan to deal with the on-site consequences of a major accident. The details are given in Schedule 5.
When?
The dates for completion of on-site emergency plans after 30 June 2005 are given in regulation 9 and are as follows:
  • before operation starts, if a plan is required because of an increase in the quantity of dangerous substances; or
  • within one year of the requirement applying, if a plan is required because of other changes e.g. a change in classification or qualifying quantity of a substance in Schedule 1 or a change in knowledge about dangerous substances generated during loss of control of an industrial chemical process.
Supply information to local authorities for off-site emergency planning purposes
Local authorities play a key role by preparing, reviewing, revising and testing off-site emergency plans for dealing with the off-site consequences of major accidents at top-tier sites. In order to fulfil this role they need information from operators. Details can be found in Schedule 5 to the Regulations and guidance will be available (see introduction). Operators will need to hold discussions with their local authorities to determine their exact needs.
When?
The information for the local authority must be supplied no later than the date the on-site emergency plan for the site has to be completed.
Provide certain information to the public about their activities
People who could be affected by an accident at a COMAH establishment must be given information without having to request it. The details are given in Schedule 6 of the Regulations but include details of the dangerous substances, the possible major accidents and their consequences and what to do in the event of an accident.

As previously mentioned, safety reports will be available to the public via public registers.

When?
The information for people who could be affected by a major accident at the establishment must be supplied 'within a reasonable period of time after the off-site emergency plan has been prepared for the establishment'. Six months would be the normal time.

Safety reports will be put on the public register shortly after receipt by the CA unless there is a request for certain information to be withheld (for national security, commercial and personal confidentiality reasons) as provided for in the Regulations.

Exclusion of Information from Public Registers on National Security Grounds

Schedule 8 of the COMAH Regulations outlines the procedure which must be followed and allocates responsibilities, in particular to the Secretary of State (SoS) who must decide which information is to be excluded and issue a direction to that effect.

Any operators of COMAH establishments requiring advice on security matters should contact their local Police Industrial Security Liaison Officer, in the first instance.

Having received security advice from the Police, the operator should write to the Secretary of State (SoS) via the addresses below, specifying the information which it is believed should be excluded from the COMAH public register:

Exclusion of Information from Public Registers on Commercial and Personal Confidentiality Grounds

Schedule 8 of the COMAH Regulations also outlines the procedure which must be followed in respect of a request that information is withheld from the public register on the grounds that the information is personally or commercially confidential.

Any such request must be made to the CA in writing and should include justification for the request. The CA must make its decision on any such request, and give the operator its decision, within 28 days of receiving the request. If the CA decides the information is not personally or commercially confidential, the operator can appeal to the Secretary of State (SoS), but must do so within 21 days. Operators wishing to appeal to the Secretary of State (SoS) should write to:

Provision of an amended safety report

If information in a safety report is excluded from the public register the operator must provide an amended report to the CA for inclusion in the register

2015-06-08