An office air handler supplies 2,000 cfm, of which 20% is measured outdoor air. What outdoor-air flow does that represent?
- A100 cfm
- 400 cfm
- C1,600 cfm
- D10,000 cfm
Where to look it up
Explicit exercise assumptions; not a universal code requirement.
Why B is correct
2,000 × 0.20 = 400 cfm. Occupant count alone is not used to invent a minimum rate; actual ventilation compliance is a separate check.