ATEX refers to the European Union directives that bear the ATEX name. They cover two areas: products and operations. The name is derived from the French title of the directives, ATmosphères EXplosibles (explosive atmospheres). The directives, in other words, are about explosion protection. Being EU directives, they have to be transposed into national law and enforced accordingly by all member states.
The rules specifically govern the marketing and operation of products in potentially explosive atmospheres and establish health and safety requirements to protect people working in such environments. The directive was originally published in 1994 by the European Community, the EU’s predecessor. It was recast in 2014.
The ATEX product directive (2014/34/EU) pertains to equipment and protective systems intended for use in potentially explosive atmospheres. The ATEX workplace directive (1992/92/EC) establishes minimum requirements for improving the safety and health protection of workers potentially at risk from explosive atmospheres.
ATEX marking
The device marking/labeling in accordance with ATEX Directive 2014/34/EU specifies the Ex zones in which a device (e.g., a pump) may be used. The ATEX marking consists of:
- Device group
- I = Mining
- II = other Industries
- Device category and area of application
- 1 = Zone 0 / 20 (permanent hazard)
- 2 = Zone 1 / 21 (occasional hazard)
- 3 = Zone 2 / 22 (rare, short-term hazard)
- G = Gases/vapors/mists
- D = Dusts
- Marking for explosion protection
- Protection type
- h = Design safety
- d = Flameproof enclosure
- e = Increased safety
- Explosion group
- IIA = Highly flammable (e.g., propane)
- IIB = highly flammable (e.g., ethylene)
- IIC = extremely flammable (e.g., hydrogen, acetylene)
- Temperature class
- T1 = ≤ 450 °C
- T2 = ≤ 300 °C
- T3 = ≤ 200 °C
- T4 = ≤ 135 °C
- T5 = ≤ 100 °C
- T6 = ≤ 85 °C
- Equipment protection level
- Ga / Gb / Gc = for gases (very high / high / normal)
- Da / Db / Dc = for dusts (very high / high / normal)
For example, the marking II 2G Ex h IIB T4 Gb means:
Equipment group II (used in other industries) in category 2 (= zone 1, occasional hazard) for gases/vapors,
explosion-proof with regard to structural safety for Ex group IIB (= highly flammable) with temperatures up to max. 135 °C, gas protection level “high.”
