Controlling Hazards and Major Accidents

When dealing with extremely dangerous substances that can cause major accidents extreme care must be taken to avoid any of these accidents occurring. Consequently to avoid this happening there is specific legislation put in place detailing the various duties then need to be undertaken when dealing with these substances.

Control of Major Accident Hazards (Amendment) Regulations 2005

The Control of Major Accident Hazards (Amendment) regulations or COMAH came into effect in June 2005 providing various amendments to the already existing Control of Major Accident Hazards Regulations 1999.

The 1999 Regulations implemented the EU Directive which was known as the Seveso II Directive and replaced the Control of Industrial Major Hazards Regulations 1984.

The Regulations are in place in order to prevent major accidents or limit the consequences for the people who live in the vicinity of establishments that hold or use specified substances.

Application of the Control of Major Accident Hazards Regulations

The Regulations apply to any establishment where a dangerous substance listed in Schedule 1 of the Regulations is present in a quantity equal to or exceeding the quantity listed in the entry for that substance, i.e. the specified threshold.

Most commonly the Regulations apply to the following industries, facilities or sites:

  • Chemical Industry
  • Storage sites for explosives
  • Nuclear sites
  • Certain other storage facilities
  • Other industries where dangerous substances in the quantities provided by the specified thresholds are used

Section 3(2) of the 1999 Regulations specifies the circumstances not covered by the Regulations. They regulations do not cover the presence of dangerous substances in the following circumstances:

  • the transport of those substances and their intermediate temporary storage by road, rail, inland waterways, sea or air, including their loading and unloading and transport to and from another means of transport at docks, wharves and marshalling yards
  • the transport of those substances in a pipeline or pumping station          

Which Substances are Considered Dangerous?

Named Substances

Schedule 1 of the 1999 Regulations as amended by the 2005 names substances as dangerous. Examples of named substances are as follows:

  • Ammonium nitrate

  • Oxygen

  • Hydrogen

  • Formaldehyde

  • Halogens

  • Petroleum products

Categories of Substances

Schedule 1 of the 1999 Regulations as amended by the 2005 Regulations provides a list of categories to which the named substances will fall into. Examples are as follows:

  • Toxic

  • Oxidising

  • Explosive

  • Flammable

  • Dangerous for the environment

  • Carcinogens

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For more information on:

  • Threshold Quantities
  • Obligations
  • Information and Notification
  • Risk Assessment
  • Major Accident Prevention Policy