Marking of pressure sensors and transmitters in accordance with ATEX Guideline 94/9/EC ? how to browse the ATEX label on pressure sensors

If pressure sensors, pressure transmitters and other field equipment are employed in the vicinity of flammable gases or dust, they may be subject to marking relative to the ATEX product guideline 94/9/EC. ATEX requires the type label of the sensor to add the ATEX marking, so usually this is labelled directly onto the sensor during production.
Close to the Notified Body and the approval number, the marking of pressure sensors also contains important information for an individual. For example, an ?X? after the approval number indicates that special conditions must be observed with all the device. These are either given in the approval document and in the corresponding manual. Most importantly, marking according to ATEX gives info on the possible areas of application and the sort of protection used for the pressure sensor:
Explosion group:
I Mining industry, II other areas useful Device class:
Used in zone 0/20 in the vicinity of von flammable gases (1G), dust (1D)
Used in zone 1/21 in the vicinity of flammable gases (2G), dust (2D)
Use in zone 2/22 in the vicinity of flammable gases (3G), dust (3D)
However, additionally, there are devices where only certain parts could be installed in other zones, for example, a pressure sensor marked 1/2G could be installed in a tank with flammable content. diaphragm seal is located on the outside of the tank, and thus in zone 1.
Examples for types of protection:
i intrinsic safety (Limitation of electrical ignition energy by limiting current and voltage)
ia for Zone 0 or Zone 20 (for Zone 20 also iaD)
ib for Zone 1 or Zone 21 (for Zone 21 also ibD)
ic for Zone 2 d
flameproof / explosion proof enclosure, ideal for zone 1/21 and 2/22 n
non-incendive, suitable for zone 2/22 m
encapsulation suitable for zone 1/21 and 2/22 Gas group and temperature class: i.e. IIC T1 for hydrogen
Note:
Further information about hydrogen can be found on the WIKA website. When you have any more questions, your contact will gladly assist you to.