USCG Exam PracticeAir conditioning, ventilation, and compressed air
A positive-displacement air compressor is running and the discharge valve is inadvertently closed. Which safety device is specifically required to protect against this condition on each compressor stage?
- A. Fusible plug
- B. Bursting disc
- ✓ Relief valveCorrect
- D. Oil-pressure safety switch
Why C is correct
NAVEDTRA 14075 §7-1 and NAVEDTRA 14104 §10-3 both state that positive-displacement compressors must never run against a closed discharge, and that each stage is therefore protected by its own relief valve. Fusible plugs and bursting discs are fitted on high-pressure receivers and lines, not on each compressor stage for this purpose.