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AIR FOR COMBUSTION AND VENTILATION
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 ceiling and one within 12" of floor on
wall connecting two spaces (see Options 1 and 2, Figure 6). You can also remove door into adjoining
room (see Option 3, Figure 6).
WARNING
REWORK WORKSHEET, ADDING THE SPACE OF ADJOINING UNCONFINED SPACE.
THE COMBINED SPACES MUST HAVE ADEQUATE AMOUNT OF AIR TO SUPPLY ALL
APPLIANCES IN BOTH SPACES.
NOTE:
Each opening shall have a minimum free area of 1 square inch per 1000 BTU’s per hour
of total input ratings of all gas utilization equipment in confined space, but not less than 100
square inches.
Figure 6
Ventilation Air From Inside Building
Summary of Contents for 42ZCBB
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