Where should exhaust fans terminate?

• A. Inside the building
• B. In a ceiling void
• C. In a mechanical room
• D. Outside the building

Answer: (D)

Exhaust must be discharged to the outside to actually remove heat, moisture, and any contaminants from the space. Venting to the exterior prevents the air from being pushed into another indoor area, which would raise humidity and odors and could spread grease or smoke. If the air were released into a ceiling void or a mechanical room, it would just circulate or accumulate in those spaces, creating moisture, mold, and potential fire hazards, and it wouldn’t achieve true exhaust of the indoor air. By terminating outside the building, the contaminated air exits the building entirely and won’t compromise indoor air quality, and it aligns with typical safety and building codes for ventilation.