What is the minimum temperature required in diesel pump rooms?

• A. 32°F
• B. 20°F
• C. 40°F
• D. 50°F

Answer: (C)

Maintaining a prudent ambient temperature in a diesel pump room helps ensure the engine and fuel system operate reliably. Diesel fuel can gel and become more viscous at lower temperatures, which can lead to clogged filters, restricted fuel flow, and hard starting. Keeping the room at a minimum of 40°F provides a buffer so the fuel remains liquid and the engine can start and run when needed, which is essential for dependable fire pump operation.

Choosing 32°F or 20°F would risk fuel waxing or freezing, making starting or operation unreliable. A higher minimum like 50°F is acceptable but not the required lower limit, since the question asks for the minimum temperature.