VENTILATION AIR
VENTILATION AIR FROM INSIDE BUILDING
This fresh air would come from an adjoining unconfined space. When venting to an adjoining space, you must provide two permanent openings: one within 12" of the ceiling and one within 12" of the floor on the wall connecting the two spaces (see Options 1 and 2, Figure 7). You can also remove door into adjoining room (see Option 3, Figure 7).
NOTE: Each opening shall have a minimum free area of 1 square inch per 1000 BTU’s per hour of the total input ratings of all gas utilization equipment in the confined space, but not less than 100 square inches.
Figure 7 Ventilation Air From Inside Building
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