The COMAH Regulations apply in Ireland where dangerous substances are present at or above specified thresholds in Schedule 1 of the Regulations. They implement the Seveso III Directive and establish lower-tier and upper-tier requirements. Operators within scope must take all necessary measures to prevent major accidents and limit their consequences for human health and the environment.
COMAH stands for Control of Major Accident Hazards. In Ireland, the relevant legislation is the Chemicals Act (Control of Major Accident Hazards Involving Dangerous Substances) Regulations 2015, commonly known as the COMAH Regulations.
The Regulations implement Directive 2012/18/EU, known as the Seveso III Directive, in Ireland.
Their purpose is to prevent major accidents involving dangerous substances and, where an accident does occur, to limit its consequences for human health and the environment.
The Health and Safety Authority is the Central Competent Authority for the COMAH Regulations in Ireland.
They are closely related but are not the same legal instrument. Seveso III is the European Directive that establishes the framework for controlling major-accident hazards involving dangerous substances.
Ireland implements that Directive through the Chemicals Act (Control of Major Accident Hazards Involving Dangerous Substances) Regulations 2015.
For an Irish business, it is therefore the Irish COMAH Regulations that establish the legal duties applying to an establishment.
No. The presence of hazardous chemicals does not automatically make a site a COMAH establishment.
Whether the Regulations apply depends principally on the dangerous substances present or likely to be present and the qualifying quantities specified in Schedule 1.
Schedule 1 contains both categories of dangerous substances and specifically named substances. The relevant classifications are based on the European Classification, Labelling and Packaging Regulation, commonly known as CLP.
A site therefore needs to understand both the classification and the maximum quantities of relevant dangerous substances that may be present.
Schedule 1 of the COMAH Regulations specifies qualifying quantities for lower-tier and upper-tier establishments.
Some dangerous substances are specifically named, while others fall within broader health, physical or environmental hazard categories.
The quantities considered are generally the maximum quantities present or likely to be present at any one time.
It is also important not to assess each substance entirely in isolation. Schedule 1 contains an addition rule that can bring an establishment within scope where several dangerous substances are present below their individual thresholds but their combined hazard contribution reaches the qualifying level.
Determining COMAH status should therefore be based on a complete inventory of relevant dangerous substances and the rules in Schedule 1.
COMAH establishes two levels of control based on the quantities of dangerous substances present.
An establishment becomes lower-tier where the relevant lower-tier qualifying quantities in Schedule 1 are reached.
Lower-tier operators are subject to a range of duties intended to prevent major accidents and manage major-accident hazards.
An establishment becomes upper-tier where the higher qualifying quantities specified in Schedule 1 are reached.
Because greater quantities of dangerous substances are involved, upper-tier operators have additional requirements, including preparation of a safety report and an internal emergency plan.
Every operator within the scope of the COMAH Regulations has a general duty to take all necessary measures to prevent major accidents and to limit their consequences for human health and the environment.
Depending on the establishment and its tier, duties can include:
Additional duties apply to upper-tier establishments.
A Major Accident Prevention Policy, commonly referred to as a MAPP, sets out an operator’s overall approach to preventing major accidents and limiting their consequences.
Both lower-tier and upper-tier COMAH establishments are required to prepare a MAPP.
The policy should reflect the hazards at the establishment and include the operator’s aims, principles of action, management responsibilities and commitment to maintaining a high level of protection for human health and the environment.
It must be implemented through suitable management arrangements proportionate to the major-accident hazards and complexity of the establishment.
Yes. Operators of upper-tier establishments must prepare and submit a safety report to the Health and Safety Authority.
Among other requirements, the safety report is intended to demonstrate that:
The legal responsibility for identifying major-accident scenarios and determining appropriate risk-reduction and mitigation measures remains with the operator.
Upper-tier establishments are required to prepare internal emergency plans addressing foreseeable major-accident scenarios and the actions required to control incidents and limit their consequences.
These arrangements can include responsibilities for initiating emergency procedures, communications with emergency services and authorities, warning people on site, staff training and the resources available for emergency response.
External emergency planning requirements also apply to upper-tier establishments and involve the relevant local competent authorities.
Storage facilities can form an important part of the measures used to prevent or mitigate major accidents where dangerous substances are present.
For establishments subject to COMAH, storage arrangements may need to consider matters such as:
The appropriate controls must be established from the site’s major-accident hazards and risk assessment rather than by selecting a storage product solely because a site is described as COMAH.
No. COMAH applies to the management of major-accident hazards across an establishment and cannot be satisfied simply by purchasing a particular storage product.
Storage design may form one part of the prevention and mitigation measures identified by the operator, but compliance also involves management systems, risk assessment, operational controls, emergency arrangements, maintenance, information and other duties required by the Regulations.
Claims that an individual chemical store makes an entire establishment “COMAH compliant” should therefore be treated with caution.
Chemstore designs and manufactures hazardous material storage solutions that can be specified around the substances, quantities, containment requirements and operational risks identified for a particular site.
For larger chemical inventories, this can include bespoke chemical warehouses and storage compounds, while dedicated hazardous chemical storage is available through our product ranges. Contact Chemstore for a bespoke quote.
The specification of a Chemstore product should form part of the site’s wider engineering and risk-management process and does not replace the operator’s duties under the COMAH Regulations.
The starting point is Schedule 1 of the COMAH Regulations. Businesses should identify the dangerous substances present or likely to be present, establish their relevant CLP classifications and determine the maximum quantities that may be present.
The lower-tier and upper-tier qualifying quantities and the Schedule 1 addition rules should then be considered.
Where there is uncertainty about the classification of an establishment or the application of the Regulations, competent regulatory or technical advice should be obtained.
The primary sources are the Health and Safety Authority and the Irish Statute Book.
This page provides general information about COMAH and Seveso III in Ireland. It does not replace the COMAH Regulations, official HSA guidance, a COMAH assessment, a safety report, a site-specific risk assessment or advice from a competent person.
Whether the Regulations apply and the measures required depend on the dangerous substances, classifications, quantities, processes and major-accident hazards associated with the individual establishment.
061 327 792
