What is the difference between ATEX and DSEAR in the UK?
Abstract
ATEX is two EU directives. DSEAR 2002 is the GB law that put the ATEX workplace directive into force, plus the fire and explosion parts of the Chemical Agents Directive, so it is wider. Ex products in GB fall under separate 2016 regulations (UKEX), which accept CE or UKCA.
"ATEX" is the name of two EU directives; "DSEAR" is the British law that employers in Great Britain actually have to follow. The Dangerous Substances and Explosive Atmospheres Regulations 2002 implemented the ATEX workplace directive 1999/92/EC together with the safety parts of the Chemical Agents Directive 98/24/EC, so DSEAR covers fire as well as explosion and all physically dangerous substances, not only explosive atmospheres. The ATEX product directive has its own British counterpart, the 2016 equipment regulations known as UKEX.
Short answer
- ATEX = Directive 2014/34/EU (equipment) and Directive 1999/92/EC (workplaces). Directives oblige states, which turn them into national law.
- DSEAR = SI 2002/2776, made under the Health and Safety at Work etc. Act 1974, in force since 9 December 2002 (zoning and coordination duties from 30 June 2003). It applies in Great Britain; Northern Ireland has its own DSEAR (Northern Ireland) 2003.
- DSEAR goes further than 1999/92/EC: it covers fire, explosion and similar energy-releasing events such as runaway reactions, from any substance meeting a physical hazard class under CLP, any substance that is dangerous because of how it is used, and combustible dust.
- Zoning, the Ex sign and equipment categories in DSEAR (regulation 7 and Schedules 2 to 4) follow 1999/92/EC almost word for word.
- Products: Ex equipment for GB is covered by the Equipment and Protective Systems Regulations 2016 (UKEX), not by DSEAR. CE marking is recognised in GB indefinitely; UKCA is an alternative.
How the two systems map onto each other
| Subject | EU (ATEX) | Great Britain |
|---|---|---|
| Workplace duties | Directive 1999/92/EC, via each Member State's law | DSEAR 2002 (also implements the safety aspects of 98/24/EC) |
| Equipment placed on the market | Directive 2014/34/EU, CE marking, notified bodies | EPS Regulations 2016 (UKEX), CE or UKCA marking, UK approved bodies for UKCA |
| Risk assessment record | Explosion Protection Document (Article 8) | Record of significant findings (regulation 5), required with five or more employees |
| Zones | Annex I | Schedule 2, regulation 7(1) |
| Equipment categories per zone | Annex II | Schedule 3, regulation 7(2) |
| Warning sign | Annex III | Schedule 4, regulation 7(3) |
| Verification before first use | Annex II, Part A | Regulation 7(4) |
| Enforcement | National authorities | HSE or local authorities (fire and rescue authorities for general fire safety); HSE also enforces the 2016 Regulations for workplace products |
The British record of significant findings is not called an "Explosion Protection Document", but regulation 5(4) asks for the same content where an explosive atmosphere may occur: the zoned places, the equipment needed for safe operation in them, confirmation that explosion safety has been verified, and the coordination arrangements. It must be reviewed regularly and after significant changes.
Where DSEAR is wider than the ATEX workplace directive
Substances. Since 1 June 2015, a "dangerous substance" under DSEAR is any substance or mixture meeting the criteria of any physical hazard class in the CLP Regulation (whether or not it is classified), any substance that creates a fire or explosion risk because of its properties and the way it is used (a high-flash-point oil heated or sprayed, for example), and any dust that can form an explosive mixture with air. HSE gives petrol, LPG, paints, varnishes, solvents and dusts from milling and sanding as examples.
Hazards. DSEAR covers fires and other energy-releasing events, not only explosions. A flammable liquid store with no zone at all still needs a DSEAR assessment of fire risk, separation, ventilation and ignition control.
Conditions. The zoning duty in regulation 7 is limited to explosive atmospheres under atmospheric conditions (HSE guidance uses -20 to 40 °C and 0.8 to 1.1 bar for this purpose), but the rest of DSEAR still applies outside that range, for example to flammable mixtures inside a pressurised reactor.
People. Self-employed persons have the same duties as employers. Health effects of substances are not covered; they fall under COSHH.
What changed for DSEAR and Ex equipment after Brexit
DSEAR is British law from 2002 and remains in force; Brexit did not create it or replace it. What changed is the product side: the 2016 Regulations now operate as a separate GB regime with UK approved bodies and the UKCA marking. Government guidance updated in 2026 confirms that the Product Safety and Metrology etc. (Amendment) Regulations 2024 extend recognition of CE marking in Great Britain indefinitely, so ATEX-certified equipment can still be used and sold there. Future changes to EU directives do not automatically change DSEAR.
Common mistakes
- "We are DSEAR compliant because our equipment is ATEX certified." Certified equipment is one measure; DSEAR requires the assessment, zoning, controls, training, emergency arrangements and the record.
- "DSEAR is only about zones." A fire risk from stored flammable liquids is a DSEAR matter even where no zone is needed.
- "No zones, no DSEAR." The regulations apply wherever a dangerous substance is or may be present at work.
- "Brexit means UKCA-only equipment." CE-marked Ex equipment remains acceptable in Great Britain.
Related on excodex
- ATEX explained: the two EU directives 2014/34/EU and 1999/92/EC in plain language
- Ex certification in other markets: UKEX, EAC, INMETRO, CCC, PESO and others
- The Explosion Protection Document (EPD) and area classification drawings under ATEX 1999/92/EC
- What is the difference between a DSEAR risk assessment and hazardous area classification?
- Standards spaces: UKEX, Directive 1999/92/EC
Standards and further reading
- Dangerous Substances and Explosive Atmospheres Regulations 2002 (SI 2002/2776), regulation 2 (definitions, as amended), regulation 5 (risk assessment) and regulation 7 (zoning): legislation.gov.uk
- HSE L138, Dangerous substances and explosive atmospheres, Approved Code of Practice and guidance (2nd edition, 2013): hse.gov.uk
- Dangerous Substances and Explosive Atmospheres Regulations (Northern Ireland) 2003 (SR 2003/152): legislation.gov.uk
- Office for Product Safety and Standards, statutory guidance on the Equipment and Protective Systems Regulations 2016 in Great Britain: gov.uk
- Directives 1999/92/EC and 2014/34/EU.
This article is general technical information prepared by the excodex editorial team. It does not replace the applicable standards, the equipment certificates and instructions, national regulations or the assessment of a competent person.