Standards & ATEX certification

To protect against equipment-related explosions, we use ATEX-marked equipment.
This equipment must comply with the technical specifications for each type of zone.
ATEX standards are regulated by European directives and specific equipment marking.

ATEX Regulations

Two European directives form the ATEX regulations. They set out the minimum standards with regard to explosive atmospheres for employers and manufacturers.

Directive 99/92/EC or ATEX 137
– Employers' responsibility for the safety of workers

Employers are required to carry out an explosion risk assessment and take the necessary measures to eliminate or reduce this risk.

Risk zone classification and signage
Keeping explosion protection records
Implementation of technical and organizational preventive measures
Compliance with electrical appliance selection criteria

Directive 2014/34/EU (recast of 94/9/EC) or ATEX 95
– Responsibility of manufacturers of equipment intended for use in ATEX zones

Manufacturers are responsible for :

Requirements for protective equipment and systems intended for use in explosive atmospheres (such as gas detectors).
Requirements for safety and control devices intended for use outside potentially explosive atmospheres, but necessary for the proper operation of protective equipment and systems (e.g. control modules).
Classification of equipment groups into categories.
Essential health and safety requirements for the design and manufacture of equipment/systems.

To comply with the ATEX directive, equipment must:

CE marked
Have the necessary certifications for hazardous areas
Meet a recognized performance standard, such as EN60079-29-1:2007 for flammable gas detectors (specific to each application)

This sign authorizes the free movement of equipment within the European Union.

ATEX equipment marking

Article 137 of ATEX directive 99/92/EC sets out the responsibilities of employers concerning the use of equipment designed for explosive atmospheres:

Prevent the formation of explosive atmospheres,
Avoid the ignition of explosive atmospheres,
Mitigate the effects of explosions.

Click here to consult the directive: Click here

The employer must carry out an assessment of explosion risks:

Probability of explosive atmosphere formation: Zone classification
Probability of ignition source: Equipment categories
Nature of flammable materials: gas groups, ignition temperature (T index), gas, vapour, mist

Regulatory marking

All electrical and non-electrical equipment and protective systems used in hazardous areas must comply with the technical requirements for each type of zone. Three categories have been defined, corresponding to the safety levels required for equipment.

What's more, specific markings identify the equipment and its characteristics.

1 - Device groups & categories

ATEX marking

ATEX classification

This regulatory marking generally needs to be supplemented by a normative marking, to check that the equipment is compatible with the physicochemical characteristics of the constituents of the explosive atmosphere.

2 - Protection mode

There are a number of different modes, depending on the application, for gases/vapors, dusts, electrical or non-electrical materials.

3 - Gas/vapour group & temperature classes

Gases/vapors are classified according to their sensitivity to ignition into three families: IIC being the most dangerous.
NB: Dusts are classified according to their state of division (particle size and conductivity) into 3 families.

The surface temperature of the material is to be compared with the self-ignition temperatures of the products. For gases/vapors, the class is indicated by a numerical code.
NB: For dusts, the maximum temperature that can be reached is directly indicated.

Gases/vapours and dust class

Temperature class

ATEX zones and IEC equipment groups

CEIEx (International Electrotechnical Commission) issues standards that are widely used in countries outside Europe and North America. CEIEx standards relate to the classification of standard zones and equipment. These standards are often found on equipment data sheets, so it's worth drawing a parallel between them and ATEX standards.