What is Atex?
Explosion danger exists in all types of industrial production. There is a risk of explosion in many industrial production processes, from mining to grain milling, from all kinds of chemical manufacturing to food production. Explosive atmospheres in production areas can be caused by gases, steam or dust. DSEAR (Dangerous Substances and Explosive Environments Regulations 2002) defines an explosive atmosphere as “a mixture of hazardous substances with air in the form of gases, vapors or dusts, under atmospheric conditions, in which combustion propagates after ignition has occurred.”
What Does ATEX Mean?
ATEX takes its name from the French phrase “ATmosphères EXplosibles” (explosive atmospheres). It describes the set of EU rules governing equipment and workplaces where a hazardous mixture like the one DSEAR defines above could form. Two directives sit at the core of ATEX: one governs the equipment manufacturers place on the market, and the other governs how employers protect workers in the areas where that equipment operates.
The Two ATEX Directives
ATEX 2014/34/EU sets the design, testing, and certification requirements for equipment and protective systems intended for use in potentially explosive atmospheres. Manufacturers must meet this directive before a piece of equipment can carry the Ex mark and be sold into the EU market.
ATEX 1999/92/EC — implemented in the UK primarily through DSEAR — sets the minimum requirements for protecting workers in workplaces where an explosive atmosphere may occur. It obligates employers to classify hazardous areas into zones, assess risk, and select equipment appropriate to those zones.
ATEX Zone Classification
Zone classification is the starting point for almost every ATEX decision that follows, since it determines which equipment category is legally usable in a given area.
Gas atmospheres:
- Zone 0: An explosive gas/air mixture is present continuously or for long periods
- Zone 1: Likely to occur occasionally during normal operation
- Zone 2: Not expected during normal operation, and if it occurs, only briefly
Dust atmospheres:
- Zone 20: A combustible dust cloud is present continuously or for long periods
- Zone 21: Likely to occur occasionally during normal operation
- Zone 22: Not expected to occur, but dust accumulations may still ignite if disturbed
How to Read ATEX Equipment Marking
Equipment approved for use in explosive atmospheres carries a standardized marking, such as Ex II 2G IIB T4 Gb. Each element carries specific meaning:
| Code | Meaning |
|---|---|
| Ex | Explosion protection applied |
| II | Equipment Group 2 (surface industries, not mining) |
| 2G | Category 2, gas atmosphere |
| IIB | Gas group (e.g. propane, ethylene) |
| T4 | Maximum surface temperature of 135°C |
Reading this code correctly at the procurement stage prevents a facility from installing equipment rated for a lower-risk zone than the one it’s actually going into.
Why ATEX Compliance Matters
Skipping ATEX compliance isn’t just a paperwork risk. Standard, non-certified equipment can spark or overheat during ordinary operation, and in a zone where an explosive atmosphere can form, that spark is enough to trigger a catastrophic incident. Beyond the direct safety exposure, non-compliance discovered during an inspection or after an accident routinely voids insurance coverage and exposes the facility operator to legal liability. Regulators in most jurisdictions treat this as strict liability territory — ignorance of a zone’s classification is rarely accepted as a defense once an incident investigation begins.
ELVA and ATEX-Compliant Solutions
ELVA Engineering supplies ATEX-certified fire detection, gas detection, spark extinguishing, and explosion protection systems for industrial facilities across Türkiye. Our product portfolio is certified for use across the full range of risk zones, from Zone 0 to Zone 2. Contact our team for an ATEX compliance assessment of your facility.
You may also find our article on dust explosion risk useful.
Frequently Asked Questions
What is the difference between ATEX and DSEAR?
ATEX is the umbrella term for the EU directives governing explosive atmospheres, covering both equipment design (2014/34/EU) and workplace safety (1999/92/EC). DSEAR is the UK regulation that implements the workplace safety directive domestically, setting out how employers in the UK must assess and control explosion risk.
How is an ATEX zone determined?
Zone classification depends on how often and how long an explosive atmosphere is present. Continuous or long-duration presence corresponds to Zone 0 (gas) or Zone 20 (dust); occasional presence during normal operation corresponds to Zone 1 or Zone 21; and rare, short-duration presence corresponds to Zone 2 or Zone 22.
What happens if I install the wrong ATEX category of equipment?
Installing equipment rated for a lower-risk zone than it’s actually placed in leaves a real ignition risk in an explosive atmosphere. It also typically breaches DSEAR or the equivalent local regulation, which can void insurance coverage and expose the operator to legal penalties.
Who needs to comply with ATEX?
Any facility that manufactures, stores, processes, or handles substances capable of forming an explosive gas, vapor, or dust atmosphere needs to comply — this spans mining, grain milling, chemical manufacturing, food production, and many other industrial sectors.
