Which deck should exhaust fans be located on to facilitate proper duct pressure?

Which deck should exhaust fans be located on to facilitate proper duct pressure?

• A. Weather deck
• B. Main deck
• C. Upper deck
• D. Lower deck

Answer: (A)

Exhaust ventilation works best when air is removed directly to the outside atmosphere with minimal resistance, so the duct system can establish a clear flow path from inside spaces to the exterior. Placing exhaust fans on the weather deck—the deck exposed to the outside environment—gives the air a direct, unobstructed route to the atmosphere. This setup leverages the outside air path and any wind aid to push contaminated air out efficiently, helping maintain a predictable pressure relationship in the ducts and reducing the chance of air being drawn back into the ship through other openings. If exhaust were placed on lower or interior decks, air could recirculate or be pulled through doors and vents, making it harder to control duct pressure and the spread of smoke or fumes.

Exhaust ventilation works best when air is removed directly to the outside atmosphere with minimal resistance, so the duct system can establish a clear flow path from inside spaces to the exterior. Placing exhaust fans on the weather deck—the deck exposed to the outside environment—gives the air a direct, unobstructed route to the atmosphere. This setup leverages the outside air path and any wind aid to push contaminated air out efficiently, helping maintain a predictable pressure relationship in the ducts and reducing the chance of air being drawn back into the ship through other openings. If exhaust were placed on lower or interior decks, air could recirculate or be pulled through doors and vents, making it harder to control duct pressure and the spread of smoke or fumes.