This study uses
makeup air vents that have free area less than or equal to the cross-sectional area of the fire.
If anything, they had expected that the homes might be too airtight, guessing that new windows, insulation and other energy-efficiency measures would decrease the
makeup air and interfere with the natural draft.
The garage entry on the left side is the source of
makeup air. Figure 2 shows CO concentration assuming multiple ducted exhaust inlets per the CMC, while Figure 3 shows an unducted design with a single exhaust inlet on the side opposite the entry.
Due to the large amount of
makeup air in the cleanrooms and the mission-critical cleanroom processes, correct operation of these freeze stats is crucial.
The
makeup air from the main part of the house should come into the closet near the ceiling or through the ceiling (see the "second thing" above).
Another common edict of smoke control is supplying
makeup air at the floor level at very low velocities (200 fpm [1 m/s] maximum)--also typical for an open, atrium space.
In a standard HVAC system, a fixed amount of OA is taken in, either by itself (
makeup air system) or mixed with a quantity of recirculated air (mixed air system).
Unless they are provided with net free ventilation area (NFVA) equal to or greater than their CFM rating, they draw the needed
makeup air from the conditioned space: A/C in the summer and heated air in the winter if they are operated at that time of year.
The only field design required for the radiator is a source of intake or
makeup air, and a duct enclosure from the radiator discharge to the building exterior.
As a result, the amount of heat generated at the stove top is less than traditional appliances, and exhaust and
makeup air requirements can be reduced--especially when paired with proper exhaust hood design, layout, and flow control.