Explosive atmospheres in Ireland: employer duties and the HSA guide

If your workplace handles flammable gases, vapours, mists or combustible dusts, Irish law expects you to assess the risk of an explosive atmosphere forming, classify the affected areas, and record your conclusions in an explosion protection document. These duties sit in Part 8 of the Safety, Health and Welfare at Work (General Application) Regulations 2007 (S.I. No. 299 of 2007), which is one part of the wider framework described in our overview of the General Application Regulations 2007. This guide walks through what the Regulations and the Health and Safety Authority (HSA) guide say, in plain terms, for employers and the managers who oversee safety.

The law is national, so the same rules apply to a Dublin-based firm as to an employer anywhere else in Ireland. This is general information, not legal advice.

Where the rules come from

Part 8 is made under the Safety, Health and Welfare at Work Act 2005. According to the HSA's guide to Part 8 (published December 2007), the Part came into effect on 1 November 2007, re-transposes the EU ATEX workplace directive (Directive 1999/92/EC) and revokes the earlier Safety, Health and Welfare at Work (Explosive Atmospheres) Regulations 2003 (S.I. No. 258 of 2003). The HSA guide describes itself as non-binding guidance rather than a legal interpretation, so the Regulations themselves are what set the duties.

The word ATEX also appears in the equipment context. The HSA guide refers to the equipment directive (94/9/EC) as implemented in Ireland by S.I. No. 83 of 1999, and says that equipment must carry the CE and "EX" marking. That guide dates from 2007, so check the current position on the official pages.

Does Part 8 apply to your workplace?

Under Regulation 168, Part 8 applies to a workplace where employees are potentially at risk from an explosive atmosphere. The Regulation lists exclusions, including:

• areas used directly during the medical treatment of patients;
• the use of gas-burning appliances covered by a specified EU directive;
• the manufacture, handling, use, storage and transport of explosives or chemically unstable substances;
• mineral extractive industries; and
• land, water and air transport covered by international agreements such as ADR, although means of transport intended for use in a potentially explosive atmosphere are not excluded.

In its guide the HSA notes that other parts of a hospital, such as corridors and laundries, are not covered by the medical-treatment exclusion. The guide gives petrol, liquefied petroleum gas (LPG), paints, varnishes and solvents as examples of flammable substances, and lists dusts of combustible materials such as coal, wood, grain, flour and sugar as capable of forming explosive atmospheres. It also flags maintenance and repair as work with often a higher potential for fire and explosion incidents.

Regulation 167 defines "workplace" widely: premises or part of premises used for or connected with work, including access, egress and facility areas, other than a public road.

Step 1: Assess the explosion risk

Regulation 169(1) requires an employer, where an explosive atmosphere is or may arise, to make a suitable assessment of the risk to employees. The Regulation says the assessment must take account of matters including:

• how likely explosive atmospheres are to occur and how long they persist;
• how likely ignition sources are, including electrostatic discharge;
• the installations, substances used, processes and their interactions;
• the scale of the effects expected; and
• spaces that are, or can be, connected to places where explosive atmospheres may arise.

This assessment sits alongside the general risk assessment duties in your safety statement. See our guide to safety statements and risk assessment under the 2005 Act for the wider picture. Regulation 169(4) allows an employer to combine existing explosion risk assessments or equivalent documents produced under other legislation.

Step 2: Classify and zone the places

Under Regulation 170(1), the employer must classify places where explosive atmospheres may occur as hazardous or non-hazardous, divide hazardous places into zones, and display a prominent sign at or near each entry point to a hazardous place. Schedule 10 supplies the detail:

Schedule 10 also says flammable or combustible substances are treated as capable of forming an explosive atmosphere unless testing shows they cannot propagate an explosion when mixed with air, and that dust layers, deposits and heaps must be treated as potential sources of explosive atmospheres. The warning sign is triangular, with black lettering and edging on a yellow background, and yellow must cover at least 50% of the sign's area.

Before a workplace containing a hazardous place is first used, Regulation 170(2) requires the employer to ensure that a competent person verifies the overall explosion safety of the workplace. The HSA guide says the person verifying must be competent to consider the particular risks at the workplace, and that the installer of new equipment, the final user or an independent person may carry out the verification.

Step 3: Prepare the explosion protection document

Regulation 169(2) requires the employer to prepare an explosion protection document "as soon as practicable and before the commencement of work". The employer must also revise it after significant changes, include it in or reference it from the safety statement, and make it available to employees. Under Regulation 169(3) the document must show, among other things:

• that the explosion risks have been determined and assessed;
• that adequate measures will be taken;
• which places are classified into zones under Regulation 170 and Schedule 10;
• that workplaces and equipment, including warning devices, are designed, operated and maintained safely; and
• the purpose of any coordination under Regulation 175.

On review, the HSA guide says the risk assessment should be reviewed at least annually, and also when developments suggest it is no longer valid or after an accident or dangerous occurrence. Regulation 171 separately requires explosion-prevention measures to be reviewed regularly and whenever significant changes occur.

Prevention, equipment and people

Regulation 171 sets a priority order for measures: prevent explosive atmospheres from forming; where that is not possible, avoid ignition, including electrostatic discharge; and limit the harmful effects of an explosion. It also requires supervision where explosive atmospheres may arise, and for leaks or releases of flammable gases, vapours, mists or dusts to be diverted, removed, contained or otherwise made safe.

Regulation 172 deals with plant and equipment. It requires that equipment is brought into service only if the explosion protection document indicates it can be safely used in an explosive atmosphere, and that, if the document does not state otherwise, equipment is selected by category for each zone:

• zone 0 or 20: category 1 equipment;
• zone 1 or 21: category 1 or 2 equipment; and
• zone 2 or 22: category 1, 2 or 3 equipment.

Where the risk assessment shows it is necessary, equipment must also be able to stay safe during a power failure, allow a competent employee to override automatic processes manually, and dissipate or isolate stored energy on emergency shutdown. Electrical installations are an obvious ignition source, so read this alongside our guide to electrical safety at work under the General Application Regulations.

Regulation 173 requires training in explosion protection that is sufficient and appropriate for people working where explosive atmospheres may arise. Where the explosion protection document requires it, work in hazardous places must follow written instructions, and a permit-to-work system must cover hazardous activities, with permits issued by a competent person before the activity begins.

Regulation 174 covers protection of employees: work clothing that does not cause electrostatic discharge for employees working in hazardous places, optical or acoustic warnings and withdrawal of workers before explosion conditions develop where necessary, and escape facilities where the explosion protection document requires them.

Shared workplaces and contractors

Regulation 175 says that where employees of different employers are at the same workplace, each employer must ensure that matters under its control comply with Part 8. Where two or more employers share a workplace with a possible explosive atmosphere, the employer responsible for the workplace must coordinate all the measures Part 8 requires. A practical approach for Dublin businesses that use contractors on site is to put the zone drawings and permit-to-work rules in front of contractors before they start. That is our suggestion, not a stated legal requirement.

Check the current text

The Revised Acts front page for the General Application Regulations 2007 says "Updated to 24 May 2023". We have not stated penalties for breach in this guide. Before acting, check the current text of Part 8 and the HSA's current guidance.

Learnsignal's offices are off Baggot Street in Dublin, and we offer in-person training from there. For current details, see our CPD pages.

Frequently asked questions

Is ATEX part of Irish law?

The Irish duties for explosive atmospheres are in Part 8 of the General Application Regulations 2007, which, according to the HSA's guide, re-transposes the EU ATEX workplace directive (1999/92/EC).

What is an explosion protection document?

It is the record required by Regulation 169. It shows that the risks have been assessed, that measures are adequate, which places are zoned, that equipment is safe and the purpose of any coordination under Regulation 175. It must be prepared as soon as practicable and before the commencement of work.

Do I need zoning if I only use small quantities?

Regulation 170 applies where explosive atmospheres may occur. The HSA guide says a risk assessment is required regardless of the quantity of flammable substances present, and that non-routine activities such as maintenance and repair should also be assessed. If you are unsure whether Part 8 applies to you, record your reasoning in the risk assessment.

Who can verify explosion safety before a workplace is first used?

Regulation 170(2) requires a competent person. The HSA guide says the installer of new equipment, the final user or an independent person may carry out the verification, provided they are competent for the particular risks.

Does Part 8 cover hospitals and clinics?

Areas used directly during the medical treatment of patients are excluded by Regulation 168, but the HSA guide says other hospital areas, such as corridors and laundries, are covered.

Explosive atmosphere duties are specific, but they follow the same logic as the rest of your safety management: assess, control, record and review.