🔍 Key Concepts

• 46 CFR requirements for pressure vessel inspections and testing on inspected vessels • Differences between boilers, air receivers, and hydraulic accumulators in terms of construction and risk • Which pressure vessels typically require periodic hydrostatic tests versus those monitored or tested by other means

💭 Think About

• Think about which of these items operates with stored elastic energy and may be designed/maintained differently from standard pressure vessels. • Consider which equipment is most critical to propulsion and safety, and therefore more likely to require periodic hydrostatic testing. • Ask yourself which of these, when properly designed and maintained, might rely more on frequent operational checks and pressure settings rather than a 4‑year hydrostatic test.

✅ Before You Answer

• Identify which items are classified as boilers under 46 CFR and normally subject to periodic hydrostatic tests. • Determine whether a repair by a certified welder affects the basic requirement for hydrostatic testing at the 4‑year inspection. • Verify which type of vessel (boiler, air receiver, accumulator) may have different inspection and testing intervals or may be exempt from hydrostatic test at the regular 4‑year inspection.