17
October 2010
AUTOMATIKPRODUKTER
AUTOMATIKPRODUKTER
ATEX – Duct Smoke Detector
7.4.2
Classification of hazardous areas
Definition of the zones in accordance with Directive 1999/92/EC
Extract:
Hazardous areas are classified in zones on the basis of frequency and duration
of the occurrence of an explosive atmosphere.
Combus-
tible sub-
stances
Frequency and
duration of oc-
currence of the
substances
Zone clas-
sification
Identification of equipment
Equipment
group
Equipment category
Dusts
Permanent,
long-term or
frequently
present
Zone 20
||
1D
Occasionally
present
Zone 21
||
2D or 1D
Short-term or
normally not
present
Zone 22
||
3D, 2D or 1D
Gasses or
vapours
Permanent,
long-term or
frequently
present
Zone 0
||
1G
Occasionally
present
Zone 1
||
2G or 1G
Short-term or
normally not
present
Zone 2
||
3G, 2G or 1G
Notes:
Layers, deposits and accumulations of combustible dusts must be considered in
the same way as is performed for every other source leading to formation of an
explosive atmosphere.
The present information is intended as a summary and does not include all
aspects that need to be considered. Further relevant laws, regulations and provi-
sions applicable in the country of application must be observed as appropriate.
