Biogas Safety first!

General requirements
5.6. Requirements for work equipment
in hazardous areas
To enable work equipment to be used in hazardous
areas (potentially explosive atmospheres, PEA), it
must be approved for use in the respective Ex zone.
European Directive 2014/34/EU (ATEX, 2014)
(ATEX Product Directive, referred to in the following
simply as ATEX), has become established as the basis
for the use of equipment and protective systems
in Ex zones (see Figure 9).
According to this directive, only equipment that is
approved for zone 0 and is correspondingly marked
may be used in zone 0. Only equipment and protective
systems of equipment group II category 1 G according
to Annex 1 of ATEX may be used.
In zone 1 only equipment that is approved for zone
0 or 1 and is correspondingly marked may be used.
Only equipment and protective systems of equipment
group II category 1 G or 2 G according to Annex
1 of ATEX may be used.
In zone 2 only equipment that is approved for zone 0,
1 or 2 and is correspondingly marked may be used.
Only equipment and protective systems of equipment
group II category 1 G, 2 G or 3 G according to
Annex 1 of ATEX may be used.
Details of the zoning must be recorded in an Ex
zone plan (see Figure 10). This must be regularly
checked to ensure that it is up-to-date, and adapted
as necessary.
Figure 10: Example of a Ex-zone plan for a biogas
plant (red = zone 1, orange = zone 2)
➀ Overpressure and underpressure protection
➁ Wall duct for submersible mixer
➂ Outlet of the membrane gas storage tank
➃ Blower of the membrane gas storage tank
➄ Space in between the membranes of the gas storage
Source: Inreetec GmbH
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