Use
N 810/820/840.18 EX
6
Translation of original Operating Instructions, English, KNF 309515-309518 06/17
2.4. Explanations of the explosion protection
marking
2.4.1. Device groups
Device group I applies to devices used in the underground and
above-ground operations of mines where there is a risk of methane
and/or flammable dusts.
Device group II applies to devices used in other areas where there
is a risk of explosive atmospheres.
2.4.2. Device categories for gas
The device category describes the frequency and duration of the
occurrence of an explosive atmosphere in the operations.
Device cate-
gory
Description*
1 G
Devices for areas in which it is expected that dangerous, explosive
atmospheres (gases and vapors) occur constantly, over long periods,
or frequently.
1 D
Devices for areas in which it is expected that dangerous, explosive
atmospheres (dusts) occur constantly, over long periods, or frequent-
ly.
2 G
Devices for areas in which it is expected that dangerous, explosive
atmospheres (gases and vapors) occur occasionally.
2 D
Devices for areas in which it is expected that dangerous, explosive
atmospheres (dusts) occur occasionally.
3 G
Devices for areas in which it is not expected that dangerous, explo-
sive atmospheres (gases and vapors) will occur. If, however, they do
occur, then only rarely and for short periods.
3 D
Devices for areas in which it is not expected that dangerous, explo-
sive atmospheres (dusts) will occur. If, however, they do occur, then
only rarely and for short periods.
Tab. 3
* according to DIN EN 13463-1
Device group I
Device group II
