Control of major accident hazards (COMAH)

The Control of Major Accident Hazards (COMAH) Regulations aim to prevent and limit the consequences of major accidents. The regulations apply if you have a qualifying quantity of dangerous substances on your site.

A major accident could involve an uncontrolled release, fire or explosion which can cause serious damage or harm to human health and the environment.

The COMAH Regulations apply mainly to the chemical and petrochemical industries, fuel storage and distribution. They may also affect businesses that store gas, manufacture and store explosives, or which have large warehouses or distribution facilities storing dangerous substances. Dangerous substances can include chemicals, flammable liquids and flammable gases.

This guide describes the types of business and the dangerous substances that the COMAH Regulations apply to. See does COMAH apply to my business?

It also explains COMAH regulated site responsibilities, including assessing risks, notifying the Health and Safety Executive for Northern Ireland (HSENI), and how to deal with incidents.