Biogas Safety first!

General requirements
Hazardous areas can be divided into zones according
to the frequency and duration of the occurrence
of hazardous explosive atmospheres (see Figure 8).
The national guidelines on the classification of areas
as Ex zones must be observed. Examples of zoning
and the associated protective measures are given in
the second part of this document.
Figure 8: Classification of Ex zones
Danger !!!
Danger !!
Danger !
Zone 0 or zone 20
An area in which a hazardous explosive atmosphere consisting of a mixture of
air and combustible gases, vapours or mists is present continuously or for long
periods or frequently.
Zone 1 or zone 21
An area in which a hazardous explosive atmosphere consisting of a mixture of air and
combustible gases, vapours or mists is likely to occur occasionally in normal operation.
Zone 2 or zone 22
An area in which a hazardous explosive atmosphere consisting of a mixture of air and combustible
gases, vapours or mists does not normally occur but, if it does, does so only rarely and for a short
period.
Figure 9: Description of an ATEX label
II 2 G Ex d IIC T4 Gb
II 2
European
Conformity
Mark
Explosion
Protec>on
Mark
Equipment
Group
Equipment
Category
„G“ for Gas
„D“ for Dusts
Explosion
Protec>on*
Protec>on
Type Code*
Gas Group*
European
Conformity
Mark
Temp Code*
Explosion
Protec>on
Equipment Mark
Protec>on
Level*
Equipment
Group
Equipment
Category
„G“ for Ga
„D“ for Du
* ATEX/IECex
* ATEX/IECex
Further information
The ATEX Guidelines can be consulted on the European Union Law
website and are available in English, Spanish, French and Portuguese.
22