COMAH notifications

The aim of the Control of Major Accident Hazards Regulations 2015 (COMAH) is to prevent major accidents involving dangerous substances and to mitigate the effects on people and the environment of those that do occur.

The Regulations are enforced by a Competent Authority (CA) consisting of:

  • HSE and the Environment Agency (EA) in England
  • HSE and Natural Resources Body for Wales (NRW) in Wales
  • HSE and the Scottish Environment Protection Agency in Scotland
  • where COMAH applies to nuclear licensed sites the regulations are enforced by the Office of Nuclear Regulation (ONR) and the relevant environment regulator

Operators of 'existing' COMAH establishments

From 1 June 2015, operators of 'existing' COMAH establishments that remain in scope of the new regulations will need to submit a new COMAH notification as required by regulation 6(1) of the new Regulations.

The new Regulations require some additional information to be submitted. This includes the names of dangerous substances and categories present or likely to be present as set out in Schedule 1 of COMAH 2015. More information on the changes to Notifications is available in A guide to the Control of Major Accident Hazards Regulations 2015 (L111). The section below, 'How do I notify' provides further information on how to submit your notification to the CA.

Operators of 'new' COMAH establishments

Operators of:

  • establishments that are constructed or come into operation on or after 1st June 2015
  • non COMAH sites that become establishments due to an increase or other change in their  inventories of dangerous substances
  • lower tier establishments that become upper tier establishments, or vice versa, on or after 1 June 2015, due to modifications the operator makes to any of the establishment's installations or activities, which result in a change in its inventory of dangerous substances

should submit a notification a reasonable period of time, usually three to four months, before the start of operation of the 'new' establishment.

Operators of 'other' COMAH establishments

Operators of establishments that come into scope or move from lower tier to upper tier or vice versa due to substance classification changes, either because of alignment with CLP or because of a new harmonised or self- classification of a dangerous substance, should submit a notification within one year of becoming an 'other' establishment.

There are also other duties placed on operators (Understanding COMAH: A guide for new entrants).

Notification is essential to enable the CA to plan its assessment and inspection programmes and to ensure that operators comply with their duties under the Regulations.

Who must notify the Competent Authority (CA)?

Organisations subject to COMAH are those which manufacture or store dangerous chemicals (including petrochemicals, pharmaceuticals and agrochemicals) and explosives in excess of threshold quantities specified in the Regulations. First, you need to determine if the Regulations apply to you by checking your (existing and likely) inventory of dangerous substances against the list in the regulations. If you think that COMAH may apply but you are not sure, or you are considering moving into the scope of COMAH, you are advised to contact your COMAH Intervention Manager (CIM) or your local HSE or environmental agency office. They will be able to provide simple advice on what you need to do if the Regulations become applicable to your activities.

The notification requirements

Essentially, what is needed is information about the operator, establishment, processes and inventory ie that you inform the CA of:

  • the name and address of the operator
  • the address of the establishment concerned
  • the name and position of the person in charge of the establishment
  • information sufficient to identify the dangerous substances and category of dangerous substances present
  • the quantity and physical form of the dangerous substances present (or likely to be present)
  • a (brief) description of the activity or proposed activity of the installation concerned
  • details of the immediate environment liable to cause a major accident or to aggravate the consequences

Guidance on the amount of information required under each heading is in the publication A guide to the Control of Major Accident Hazards Regulations 2015 (L111). If the Regulations do apply to you, you are strongly advised to obtain this publication.

If you have any queries about preparing your notification, you can contact the Competent Authority by email [email protected].

How do I notify

  1. You must use the COMAH: Notifications form and submit it to the Competent Authority by email to [email protected].
  2. Your notification will be acknowledged.
  3. If you do not receive an acknowledgement within 10 days, please contact us on the email above.

Please note notifications will only be accepted via the route described above.

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2022-02-28