🔍 Key Concepts

• 46 CFR requirements for boilers and pressure vessels • Specific Coast Guard limits on using tubular gage glasses versus more protected types (like flat glass or remote indicators) • Difference between design pressure and operating/allowable pressure for fittings on boilers

💭 Think About

• Look up the exact 46 CFR section dealing with boiler water level indicators or gage glasses, and see if it sets a specific psig limit for tubular types. • Ask yourself: at what pressures does the Coast Guard start requiring stronger or more protected types of water level indicators instead of simple tubular glass? • Compare the answer choices to typical marine boiler pressures and think: which of these seems like a regulatory safety cutoff, not just a convenient round number?

✅ Before You Answer

• Verify the exact CFR citation that governs boiler water level indicators and gage glasses (in 46 CFR, engineering/boiler equipment section). • Confirm that the section you read specifically mentions “tubular gage glass” and not some other type of water level indicator. • Double‑check that the pressure limit is given as psig (gauge pressure) and matches one of the answer options before choosing.