What is the required ventilation for a 15,000 square foot auditorium?

What is the required ventilation for a 15,000 square foot auditorium?

• A. 33,750 CFM
• B. 6,000 CFM
• C. 15,000 CFM
• D. 50,000 CFM

Answer: (A)

Ventilation for a large assembly space is often set using a rate per square foot to ensure enough fresh outdoor air for many people. A common design target for auditoriums is about 2.25 CFM per square foot. Multiplying by the floor area gives 15,000 ft^2 × 2.25 CFM/ft^2 = 33,750 CFM. That supply rate helps dilute contaminants and maintain comfort for peak occupancy. If you assume a typical ceiling height around 10 ft, the volume would be about 150,000 ft^3, which yields roughly 13.5 air changes per hour with this ventilation rate—reasonable for an auditorium during active use. The other stated rates are either too low to provide adequate outdoor air or unnecessarily high; the 33,750 CFM figure aligns with common practice for this size of space. In real design, exact values come from building codes and ASHRAE standards, but this rule-of-thumb explains why 33,750 CFM is the appropriate choice here.

Ventilation for a large assembly space is often set using a rate per square foot to ensure enough fresh outdoor air for many people. A common design target for auditoriums is about 2.25 CFM per square foot. Multiplying by the floor area gives 15,000 ft^2 × 2.25 CFM/ft^2 = 33,750 CFM. That supply rate helps dilute contaminants and maintain comfort for peak occupancy. If you assume a typical ceiling height around 10 ft, the volume would be about 150,000 ft^3, which yields roughly 13.5 air changes per hour with this ventilation rate—reasonable for an auditorium during active use. The other stated rates are either too low to provide adequate outdoor air or unnecessarily high; the 33,750 CFM figure aligns with common practice for this size of space. In real design, exact values come from building codes and ASHRAE standards, but this rule-of-thumb explains why 33,750 CFM is the appropriate choice here.