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New obligations on companies facing major industrial accidents

The Control of Major Accident Hazards (COMAH) Regulations 2015 will come into effect on 1 June 2015, replacing the COMAH Regulations 1999. They will implement Seveso-III (Directive 2012/18/EU).

The overarching aim of the Regulations is to prevent major onshore accidents involving dangerous substances and limit the consequences to human health and the environment, should such an accident occur. Sites fall within the Regulations where dangerous substances are used or stored (mainly in the chemical, petrochemical, logistics and metal refining sectors) above certain thresholds, known as lower tier and upper tier. The operators of sites within each tier must adhere to certain requirements. Although industry will already be familiar with the 1999 Regulations (as amended), the 2015 Regulations expand the regime's scope and contain some new or changed duties such as:

  • Increased substance list. The list of substances covered by the Regulations has been updated and aligned to the Classification, Labelling and Packaging Regulation 2008 (CLP). CLP is based on a global classification system for chemicals. As a result some sites will change tiers, others may move out of scope entirely or become COMAH sites for the first time.
  • New toxicity categories. The generic classifications 'toxic' and 'very toxic' will be replaced with acute toxic categories 1-3 with reference to specific exposure routes.
  • Safety reports. Existing sites will be required to review their safety reports and update them in accordance with the 2015 Regulations. For a number of sites it is anticipated there won't be a need to change actual safety management arrangements, unless a new dangerous substance is within scope as a result CLP changes.
  • Emergency planning. There will be a new requirement for co-operation by designated authorities (such as government agencies or health bodies) in tests of the external emergency plan. Most COMAH sites will have to review their emergency plans, for example, provide extra information on how the public is warned and what action should be taken in the event of a major accident.
  • Public information. Linked to the emergency planning point above, there are stronger public information requirements including a duty for lower tier establishments to provide public information. There are also provisions for the public to be provided with up-to-date electronic information relating to COMAH sites. This change is particularly influenced by the Aarhus Convention, which requires greater access to environmental data.
  • Broader domino effect. Sites designated as part of a 'domino group' (a group where the likelihood or consequences of a major accident may be increased because of the location and proximity of other establishments and the dangerous substances present there) will need special consideration in terms of emergency planning, and testing of the off-site response. The operators in the group are expected to cooperate with each other in supplying relevant information to the local authority.
  • Inspections. To promote greater compliance, the competent authority (the Health and Safety Executive acting jointly with the Environment Agency) will have expanded inspection powers. For example it will prepare programmes for routine inspections of sites. 
  • Local authorities. Following a major accident the local authority will be obliged to inform people who are likely to be affected.

While not a major overhaul of the COMAH regime, the 2015 Regulations will impose increased regulatory burdens for the operators of certain sites, and could bring some sites within the regime for the first time.

Companies have until 1 June 2015 to put in place mechanism to comply with these new rules.