Determination air when general ventilation
We now turn to the definition of air in the general ventilation.
If you can not determine accurately the amount of emitted pollutant, but are known for their quality indicators, the only method for determining air is empirical: the designated multiplicity of knowing pomescheinya cubic content is calculated in air, using the computational formula
L = Vn [DOE / h], (29;
where V  the inner space cubic kilometers;
iiair exchange in 1 hour, adopted on the basis of experience and, by analogy with existing shops.
When determining the air on the multiplicity need a critical approach to the available literature data. First, we should pay attention to unhealthy conditions for the allocation parameters n correctly identify a scheme to remove them (or general exchange zonal hood, place intake of polluted air, a way to feed flow). Then you should take into account the height of the room, on which the value of V (if the height is normal for the premises, over or under). Only after a comprehensive analysis is possible to find the correct value of n.
If given in the literature, the value of n found for the general exchange of experience drawing, applying the zonal ventilation appropriate to reduce n to 1.5 times or more, which is very essential for large cubic shop.
If you know the amount of pollutant emitted, then the definition of the required air for general ventilation amenable to calculation.
The calculation formula for this case
L =  [m * / h], (30)
where G  the number of emitted pollutant (gas, vapor, aerosols) in g / h; extra  maximum permissible concentration of harmful substances in the working area of the premises in mg / m \ g  coefficient accounting for uneven allocation of pollutant by their distribution on the premises, we call this coefficient of inequality. It is understood that the input air does not contain any gas hazards and, consequently, Apache = 0.
