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Regulation and guidance

If your business manufactures, stores or uses dangerous substances, such as oil products, natural gas, chemicals or explosives, in significant amounts, the Control of Major Accident Hazards (COMAH) Regulations apply to you.

Control of Major Accidents Hazards 1999

The Control of Major Accident Hazards Regulations 1999  (COMAH regulations) aim to ensure that businesses take all necessary measures to:

  • prevent major accidents which involve dangerous substances
  • limit the consequences to people and the environment of major accidents from hazardous substances

The regulations operate on two levels depending on the establishment's status. These are divided into two categories: 'lower tier' and 'upper 'tier'.

  • COMAH

    If your business manufactures, stores or uses dangerous substances in amounts that exceed the defined quantities, the COMAH Regulations apply to you