What is the main aim of the Regulations?

The purpose of the COMAH Regulations is to prevent major accidents involving dangerous substances and limit the consequences to people and the environment of any accidents which do occur.

The COMAH Regulations 2015* implement the majority of the Seveso III Directive (2012/18/EU) in Great Britain (Northern Ireland produces its own regulations).

The land-use planning requirements from the Directive are implemented through planning legislation.

These Regulations replace the 1999 Regulations and are in force from 1 June 2015.

Who is affected?

An establishment having any dangerous substance specified in Schedule 1 (page 84*) present at or above the qualifying quantity is subject to the Regulations.

There are two thresholds, known as lower tier and upper tier. The two flow charts in Appendix 1 (page 117*) give guidance on determining whether the Regulations apply to you, at what tier and to which type of establishment they apply.

The Regulations define dangerous substances using the Classification, Labelling and Packaging Regulation 2008 (CLP). CLP is based on a global classification system for chemicals. CLP is amended from time to time in line with technical and scientific development.

These amendments are known as ‘Adaptations to Technical Progress’, or ATPs, and are usually published at least annually. Therefore, any reference to CLP in the COMAH Regulations will always be to the latest version.

What do you need to do?

Firstly, you need to determine if these regulations apply to you. Schedule 1 of the Regulations (page 84*) contains rules for aggregating sub-threshold quantities of dangerous substances in the same or similar generic categories.

It also sets out the rule for excluding amounts less than 2% of their threshold, if they are located so that they cannot initiate an incident elsewhere on site. Some examples of how these rules work are given in Appendix 2 (page 119*).

Full details can be obtained from the H&SE publication (L111 (Third edition) Published 2015)*


*Contains public sector information licensed under the Open Government Licence v3.0.

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