Air-Care FG0157, Руководство по установке

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So, a room that is 15 feet wide by 40 feet long with an 8-foot ceiling would require a
negative air machine with:
If that room had a common ceiling return plenum, making the ceiling deck 11 feet high,
then:
Now here is the tricky part, what if the drop is NOT at the minimum? The air should be
flowing from outside into the Clean Zone (3), then from Zone 3 to Zone 2 (slightly
Contaminated, and finally into the most contaminated Zone 1. If the containment is not
well sealed or the Door flaps between zones pull open with the airflow, you will need to
increase the CFM or reduce the airflow into the area. Remember, the recommended air
exchange rate is from 4 to 12 air changes per hour.
If this area requires a higher-pressure difference, you may need to go as high as 12
changes per hour, which means you would divide by 5, which gives us 1320 cfm for the
same area that required only 440 cfm if it were tighter.
As the filters become loaded, the effective cfm will drop slightly, so be sure you have a
little more capacity than the minimum. By the same token, if you have too much
capacity, it is possible to pull down the containment walls, with potentially disastrous
results.
15 x 40 x 8 = 320 cfm
15
Length x Width x Height = cfm
15
15 x 40 x 11 = 440 cfm
15
15 x 40 x 11 = 1320 cfm
5
Most
Contaminated
Area 1
Contents Cleanup
Area 2
Clean
Area 3
.02” W.G.
.04” W.G.
.02” W.G.
Negative
Air Mach
Air
Scrubber