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COMAH regulations altered under Seveso III Directive

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June saw the implementation of the European Union’s Seveso III Directive, which brings some changes to the ‘Control of Major Accident Hazards’ (COMAH) regulations in the UK.

The adapted directive, which replaced the Seveso II directive, focuses on the new system of classification of dangerous
substances under the European Regulation on Classification, Labelling and Packaging.

So what are the changes being implemented by the COMAH regulations 2015 because of Seveso III?

The scope of the Seveso III Directive is based on the EU legislation on the classification, labelling and packaging of chemical substances and mixtures.

There are some changes in both named categories of dangerous substances and named dangerous substances. The toxicity categories have moved from ‘Very Toxic’ and ‘Toxic’ to ‘Acute Toxic Categories 1 to 3’ with exposure routes (dermal, oral and inhalation) specified in some cases.
In addition to the changes in toxicity there is a new category of ‘flammable aerosols’. In the named dangerous substances, heavy fuel oil and ‘alternative fuels serving the same purpose and with similar properties’ have been moved to the named substance entry for ‘Petroleum Products’, and biofuels have been included in the entry of ‘Liquefied flammable gases’.

Determining whether the Directive applies will be more complex for both industry and regulators, particularly in relation to mixtures and for sites close to the ‘Upper Tier’ threshold limits or just outside of scope of the COMAH Regulations 1999.

COMAH establishments are classified as either ‘Upper Tier’ or ‘Lower Tier’, dependent on the nature and quantities of materials involved. For example, in the petroleum products sector, the threshold quantity for a ‘Lower Tier’ site is 2,500 tonnes, and the threshold for an ‘Upper Tier’ site is 25,000 tonnes.

These changes mean that from 1 June 2015 a number of sites may:
• Enter the regime at the ‘Lower’ or ‘Upper Tier’ threshold
• Move from the ‘Lower Tier’, or vice versa
• Leave the regime completely

The changes will also mean that:

• All establishments will have to provide basic public information about their sites – ‘Upper Tier’ establishments will be required to provide more information than ‘Lower Tier’. This information must be permanently and electronically available and kept up to date. It will be held on a postcode/operator name/establishment name searchable, account-based website hosted by the COMAH Competent Authority on the Health and Safety Executive (HSE) website.

• Further information including safety reports and inspection reports will have to be made available on request.

The requirement under Seveso II for a flexible risk/hazard based system for inspection will continue under Seveso III, which means the frequency of site visits will continue to be based on the risk/hazard profile of the site.

Notifications from operators will have to include information about neighbouring establishments and other nearby sites where they are relevant to the major accident hazard scenarios. COMAH establishments will also be required to provide information about their inventories under CLP rather than CHIP. This means that under the COMAH Regulations 2015, establishments will be required to notify to demonstrate that they fall into scope and under which tier.

Safety reports
Upper Tier establishments will still be required to produce safety reports. All ‘Upper Tier’ establishments will need to reclassify their inventories from CHIP to CLP to be attached to their safety reports. Guidance is available for operators to explain what they need to do to ensure their safety reports are compliant with COMAH 2015 and by what date.

Emergency planning
The fundamental requirements of emergency planning from COMAH 1999 will remain under Seveso III/COMAH 2015.
The Directive has made more explicit the requirement for ‘Lower Tier’ establishments to have appropriate on-site emergency planning arrangements in place. COMAH can apply at various sites including chemical manufacturing sites, chemical warehouses, oil refineries and terminals, gas storage sites and pharmaceutical manufacturers.

Currently there are just under 900 COMAH establishments in the UK. The aim of the COMAH regulations is to prevent major accidents involving dangerous substances and limit consequences to people and the environment of any that do occur. The regulations are enforced by the appropriate authority, which is either the HSE or the Office for Nuclear Regulation (for licensed nuclear site) and the appropriate environment agency – the Environment Agency for England, Scottish Environment Protection Agency for Scotland or the Natural Resources Body for Wales.

There are around four reportable major accidents a year in the UK. Within COMAH, a major accident is a major emission, fire or explosion, leading to serious danger to human health or the environment – immediate or delayed, inside or outside the establishment and involving one or more dangerous substances. One of the best known major accidents was the explosion and fire at the Buncefield oil storage refinery in 2005.

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