Biogas Safety first!

Specific requirements
emergency power exercise. The emergency power
unit must be properly earthed in order to prevent the
tripping of residual-current-operated circuit breakers.
The labelling of the switchgear cabinet must be
easily comprehensible.
If the emergency power unit is potentially used for
more than one business/type of business:
ensure that in emergency operation each connected
user is able to draw at least the minimum
amount of energy from the emergency power
supply defined in advance;
make technical provisions to ensure that in
emergency operation each connected user
is able to draw only the maximum amount of
energy from the emergency power supply defined
in advance.
18. Requirements for lightning protection
The matter of lightning protection at biogas plants
must be managed in accordance with national regulations
and the regional risk of lightning strikes.
There is a basic distinction between external and
internal lightning protection. Internal lightning protection
serves to prevent surge damage within the
installation. External lightning protection by means
of lightning rods serves to divert lightning strikes
that would hit the protected installation directly.
Technical protective measures
Biogas plants should have at least internal lightning
protection. A surge arrester (internal lightning protection)
and consistent equipotential bonding are
therefore required for the electrical installation and
the facilities for electronic control, data processing
and telecommunications. Experience to date suggests
that external lightning protection (intercepting
devices, arrester equipment, earthing system etc.) is
not generally necessary.
Organisational protective measures
The matter of lightning protection should be taken
into consideration in the hazard assessment carried
out for the construction and operation of the biogas
plant.
Further information concerning
lightning protection can be found
within the norm DIN EN 62305.
19. Requirements for rooms with substrate-carrying and / or
gas-carrying plant parts
Rooms with substrate-carrying and/or gas-carrying
plant parts include the CHP unit installation room,
pump room, etc.
Technical protective measures
General requirements
As a general rule, maintenance and control stations
and the controls of valves, agitation, pumping and
flushing equipment should always be situated above
ground level. If this is not possible, adequate technical
ventilation must be provided with at least five air
changes per hour.
Requirements for CHP unit installation rooms
If it is not possible to ensure that all gas-carrying
plant parts in CHP unit installation rooms are permanently
technically leak-tight, sources of ignition
must be avoided and if applicable explosion protection
zones must be designated. Explosion protection
zones in installation rooms can be restricted or avoided
by taking additional measures, such as a forced
ventilation system with monitoring of the air flow or a
gas warning device coupled with ventilation.
Depending on the nature of the gas, the detecting element
of the gas warning device should be mounted
above or in the vicinity of possible sources of released
gas, taking into account the effects of the
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