The ventilation purge worksheet shows an exhaust fan moves 140 cubic feet per minute for 16 minutes. How much air is moved?
Correct Answer
A) 2,240 cubic feet.
Air volume equals airflow times time: 140 cfm for 16 minutes equals 2,240 cubic feet.
Why This Is the Correct Answer
Air volume equals airflow times time: 140 cfm for 16 minutes equals 2,240 cubic feet.
Why the Other Options Are Wrong
Option B: 2,080 cubic feet total.
2,080 cubic feet total. is below the supported result for mechanical airflow calculation; it likely omits allowance, conversion, coverage, or final round-up.
Option C: 2,300 cubic feet total.
2,300 cubic feet total. is above the supported result for mechanical airflow calculation; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Option D: 2,520 cubic feet total.
2,520 cubic feet total. is above the supported result for mechanical airflow calculation; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Memory Technique
Measure to air, adjust for volume, then let Checking Exhaust set the finish line.
Reference Hint
Study anchor (closed-book): memorize Mechanical airflow calculation from California Mechanical Code, California Code of Regulations Title 24. / Title 24 California Mechanical Code exhaust airflow concepts; know the rule or calculation trigger without relying on exam-room lookup.
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