ATEX & Explosion Proof Products

General Information

According to 94/9/EC, a device that is to be used in an environment at risk of explosion may only be brought into the market if it satisfies the standards specified in the norm.

Compared with the previous directives, it must be noted that the specification refers not only to electrical but also to mechanical equipment (e.g. cylinders).

Devices are divided into categories and groups to accurately define the conditions of use. This definition is marked on the device and may appear as follows:

There are 2 groups of devices.
Devices of Group I, Category M are for use in underground mines and their above ground equipment, which are at risk from firedamp and/or inflammable dusts. (This is not given further coverage in this document).
All other areas at risk of explosion are combined in Device Group II.

EEx defines that this is an electrical device.

This defines which measures are used to ensure explosion protection.
The following ignition protection classes are used by AIRTEC:
m = Encapsulation, ia = Intrinsic safety, c = Safe by design
Other ignition protection classes are defined in EN 50014: 1997. The abbreviations are currently under review discussion.
It should be noted that devices in ignition protection class ia may only be supplied from circuits that are certified to be intrinsically safe.

Device group II is sub-divided into Explosion Groups A, B or C.
This classification is dependent on the typical material properties of the gases and vapors that occur.
The hazard level of materials increases from Explosion Group IIA to IIC. The requirements for the devices increase accordingly. If a device is approved for IIC, it can be used for all other explosion groups. Alternatively, the chemical formula or the name of the material can be stated here.

It must be ensured that the ignition temperature of an inflammable material is not reached during operation. For this purpose, the maximum surface temperature of a device must be less than the minimum ignition temperature. For this reason, the maximum surface temperature of equipment for use with inflammable gases, vapors or mists is specified in temperature classes. For dusty environments, the maximum surface temperature is specified in °C.