Biogas Safety first!

Specific requirements
7. Requirements for installation rooms for gas storages
Technical protective measures
Installation rooms for gas storages must have nonclosable
air inlets and outlets that allow cross-ventilation.
Where natural ventilation is used, the air inlet
must be positioned near the floor and the air outlet in
the opposite wall near the ceiling.
Doors must open outwards and must be lockable.
The safety distances as defined in the section on the
fire protection concept must be taken into account.
Organisational protective measures
Clearance measurement is essential prior to work in
hazardous areas. Written permission is required for
work involving the use of an open flame.
Classification of Ex zones
The gas bag lies on the ground and is protected from
the weather by a fixed housing. The housing is accessible
all-round even when the bag is full.
Gas storage facility
If a technical ventilation system is installed it must
be ensured that the exhaust air is extracted from the
ceiling area. The exhaust air must be expelled directly
into the atmosphere. The forced ventilation system
must be dimensioned such that a maximum possible
gas volume is diluted to a maximum gas concentration
of 20 % LEL in the installation room.
The air inlets and outlets must each have the following
minimum cross-sections:
Gas storage volume
up to 100 m³
Cross-section
700 cm²
In inside spaces
Constant ventilation of the space between the
gas bag and the housing; flow monitoring and
concentration monitoring; installation of a gas
overpressure protection device and installation
of a gas low pressure switch.
Zone 2: Inside the housing and within 3 m of all
openings to other rooms, and in the vicinity of
openings to the open air with the exception of
the gas overpressure protection devices. In the
interior, the same zone as the connected gas
system.
Natural ventilation of the space between the
gas bag and the housing; installation of a gas
overpressure protection device and installation
of a gas low pressure switch.
Zone 1: inside the housing
Zone 2: within 3 m of all openings. In the interior,
the same zone as the connected gas system.
Outdoors
Zoning outdoors is essentially the same as in inside
spaces. However, the effects of weather outdoors
generally make it possible to define a zone with lower
requirements than those for comparable situations
indoors, or to reduce the extent of the zone.
up to 200 m³
over 200 m³
1000 cm²
2000 cm²
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