USCG Exam PracticeAuxiliary machinery and mechanical systems
Under 46 CFR §56.50-80, sight-flow glasses may be used in lubricating-oil systems provided they meet a specific fire-resistance standard. Which of the following correctly states that standard?
- ✓ They must withstand exposure to a flame at 927 °C (1,700 °F) for one hour without appreciable leakage.Correct
- B. They must withstand exposure to a flame at 760 °C (1,400 °F) for 30 minutes without appreciable leakage.
- C. They must withstand exposure to a flame at 927 °C (1,700 °F) for 30 minutes without appreciable leakage.
- D. They must withstand exposure to a flame at 1,093 °C (2,000 °F) for one hour without appreciable leakage.
Why A is correct
46 CFR §56.50-80(h) specifies that sight-flow glasses used in lubricating-oil systems must withstand exposure to a flame at a temperature of 927 °C (1,700 °F) for one hour without appreciable leakage. The duration is one hour, not 30 minutes, and the temperature is 927 °C, not 760 °C or 1,093 °C.
Cited:46 CFR §56.50-80