FE FE Recharging & Hydrostatic Testing 2 — Questions and Answers
Question 1: What is the correct hydrostatic test pressure for a stored-pressure dry chemical extinguisher rated at a 195 psi service pressure?
- 195 psi
- 250 psi
- 300 psi
- The test pressure is stamped on the cylinder and typically 1.5–2× service pressure (Correct answer)
Correct answer: The test pressure is stamped on the cylinder and typically 1.5–2× service pressure
The hydrostatic test pressure is stamped on the cylinder by the manufacturer and is typically 1.5 to 2 times the service pressure.
Question 2: What information must be recorded on a fire extinguisher after hydrostatic testing?
- Inspector name only
- Test date, test pressure, and tester identity stamped or labeled on the cylinder (Correct answer)
- Only the next test due date
- Manufacturer part number
Correct answer: Test date, test pressure, and tester identity stamped or labeled on the cylinder
After hydrostatic testing, the test date, pressure used, and the identity of the testing facility must be permanently marked on the cylinder.
Question 3: During hydrostatic testing, what condition in the test water indicates a cylinder must be condemned?
- Slight bubbling during pressurization
- Leakage, deformation, or failure to hold test pressure (Correct answer)
- Change in water temperature
- Water turning slightly cloudy
Correct answer: Leakage, deformation, or failure to hold test pressure
Any leakage, permanent deformation, or inability to hold the test pressure means the cylinder must be condemned and removed from service.
Question 4: Which regulatory authority governs the hydrostatic testing of fire extinguisher cylinders in the United States?
- EPA
- DOT (Department of Transportation) (Correct answer)
- OSHA
- CPSC
Correct answer: DOT (Department of Transportation)
The DOT regulates the design, manufacture, testing, and marking of pressure vessels including fire extinguisher cylinders.
Question 5: What type of hydrostatic test method involves filling the cylinder with water, pressurizing it, and measuring permanent expansion?
- Proof pressure test
- Water jacket test (Correct answer)
- Pneumatic test
- Burst test
Correct answer: Water jacket test
The water jacket test measures total and permanent expansion by immersing the pressurized cylinder in a water-filled jacket and recording displaced water.
Question 6: What maximum permanent expansion percentage typically requires a cylinder to be condemned during hydrostatic testing?
- 2%
- 5%
- 10% (Correct answer)
- 15%
Correct answer: 10%
A cylinder exhibiting permanent expansion exceeding 10% of total expansion is typically condemned as structurally compromised.
FE FE Recharging & Hydrostatic Testing 2
What is the correct hydrostatic test pressure for a stored-pressure dry chemical extinguisher rated at a 195 psi service pressure?