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4) The calculation volumetric flow rate of air, when there is the excess
moisture vapor

1000 W
L  ,
  (d  d 1 )
2
where W – the intensity of emissions vapor moisture, kg/h;
3
ρ - density of air, kg/m ;
d1 and d2 - moisture content in the removed (exhausted) and incoming
(makeup) air, g/kg.

With the simultaneous emissions in industrial areas: harmful substances, heat,
and moisture, we should take the largest amounts of air (L), which is obtained by
calculations for each of the industrial discharge.

5) The method for determining the required amount of air by the multiplicity
of air exchange.
It is used for rough calculations when unknown species and quantity of
hazardous substances that are released in the premise
L=K·V,
K - the multiplicity of air exchange (shows how many times per hour air
changes in the premise, usually K = 1....10), 1/h,
V – the volume of the premise.

8.4 Natural Ventilation

Natural ventilation is the process of supplying air to and removing air from an
indoor space without using mechanical systems.
It refers to the flow of external air to an indoor space as a result of pressure
differences arising from natural forces. There are two types of natural ventilation
occurring in buildings: wind driven ventilation and buoyancy-driven ventilation.

Wind driven ventilation arises from the different pressures created by wind
around a building or structure, and openings being formed on the perimeter which
then permits flow through the building.
Buoyancy-driven ventilation occurs as a result of the directional buoyancy
force that results from temperature differences between the interior and exterior.
Since the internal heat gains which create temperature differences between the
interior and exterior are created by natural processes, including the heat from people,
and wind effects are variable, naturally ventilated buildings are sometimes called
"breathing buildings".

The impact of wind on the building form creates areas of positive pressure on
the windward side of a building and negative pressure on the leeward and sides of
the building. Thus, the building shape and local wind patterns are crucial in creating
the wind pressures that will drive air flow through its apertures. In practical terms

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