Smoke Exhaust Fan Sizing Calculator

Calculate smoke exhaust fan capacity based on fire size, ceiling height, and desired smoke layer height.

Total floor area of the smoke zone or atrium.
m²
Height from floor to ceiling or roof deck.
m
Design fire heat release rate. Typical: 1000-5000 kW for sprinklered spaces.
kW
Minimum clear height above floor. Must be above highest occupied level, typically 1.8-3 m above floor.
m

Results

Mass Flow Rate-kg/s
Exhaust Volume Flow-m³/s
Fan Capacity Required-CFM
Number of Fans (at 30,000 CFM each)-
Smoke Layer Temperature-°C
References: NFPA 92 — Smoke Control Systems, ASHRAE Smoke Management Handbook.