Alfa Network QUICK User Manual page 16

1.2 FORCED VENTILATION
Forced ventilation can be obtained with systems equipped with electric fans. The
actual flow rate must be no less than 1,72 m /h per kW.
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iThe air velocity near the installation must not disturb the operators and must have
the following characteristics:
The air velocity next to the exhaust hood must be between 0,25 m/s and 0,5 m/s.
The make-up air velocity must be less than or equal to 0,15 m/s up to 2 metres from
the walking surface.
The air flow vents in the premises, facing outwards, must have the following
characteristics:
To be conveniently located so as not to create a short circuit in the air flow.
To be protected by grilles.
For LPG installations, at least 1/5 of the natural ventilation surface with a minimum of
100 cm , must be coming from the floor as LPG is heavier than air and tends to settle
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in the ground.
2. AERATION
The required aeration may be obtained through the implementation of one of the
systems described in the following paragraphs.
2.1 FORCED AERATION SYSTEMS
The hourly flow rate of the system must be at least 1,72 m per kW referred to the
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total rated thermal output of the installation without compromising the possibility of
supplying some fresh air in the room for other purposes not exclusively related to the
safety of the appliances using gaseous fuels. The gas supply must be directed to the
equipment and must be stopped in the event that the air flow rate should fall below
the value specified above. In this case, the gas distribution should be allowed only
manually.
ATTENTION
Always contact a qualified technician.
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