RMGA System Testing 4 — Questions and Answers
Question 1: What type of gas must NOT be used to perform a pressure leak test on an oxidizer (oxygen or nitrous oxide) medical gas pipeline?
- Dry nitrogen
- Oil-free dry air
- Compressed oxygen (Correct answer)
- Helium
Correct answer: Compressed oxygen
Oxygen itself must not be used for pressure testing because high-pressure oxygen in contact with system contaminants or lubricants creates a serious fire and explosion hazard.
Question 2: An RMGA notices that a medical gas outlet station label reads 'O₂' but the outlet body is color-coded green and has a DISS connector for oxygen. What additional verification should be performed?
- Visual inspection is sufficient; no further testing is needed
- Cross-connection test and gas purity analysis at that outlet (Correct answer)
- Replace the label and retest pressure only
- Confirm the zone valve is closed
Correct answer: Cross-connection test and gas purity analysis at that outlet
Visual labeling and physical connector verification alone are insufficient; a cross-connection test and gas analysis must confirm the correct gas is actually being supplied to that outlet.
Question 3: During medical gas system testing, which of the following alarm conditions must be tested and verified to function correctly?
- Master alarm panel only
- Area alarm panels only
- Both master alarm panels and area alarm panels (Correct answer)
- Emergency shutoff valves only
Correct answer: Both master alarm panels and area alarm panels
NFPA 99 requires that both master alarm panels (at the source) and area alarm panels (at each zone) be tested and verified to annunciate correctly during system testing.
Question 4: What is the significance of the 'blow-down' test performed on WAGD (Waste Anesthetic Gas Disposal) systems?
- It measures the oxygen content of waste gas
- It verifies the system can achieve adequate flow and negative pressure to capture waste anesthetic gas (Correct answer)
- It tests the pressure relief valve setting
- It confirms cross-connections between WAGD and medical air
Correct answer: It verifies the system can achieve adequate flow and negative pressure to capture waste anesthetic gas
The blow-down test confirms that the WAGD system can generate sufficient negative pressure and flow to effectively capture and remove waste anesthetic gases from operating room equipment.
Question 5: According to NFPA 99, after a repair is made to a medical gas pipeline, which tests must be repeated before returning the system to service?
- Only a visual inspection of the repair
- Leak test and cross-connection test for the affected section (Correct answer)
- Full system re-testing including all 24-hour standing pressure tests
- Only a purity test at the nearest outlet
Correct answer: Leak test and cross-connection test for the affected section
After any repair, NFPA 99 requires at minimum a pressure leak test and a cross-connection test on the affected portion of the system before returning it to service.
Question 6: When conducting a source equipment test on a bulk liquid oxygen system, what condition triggers the activation of the reserve supply alarm?
- When the liquid oxygen temperature exceeds safe limits
- When the primary supply reaches a predetermined low-level setpoint (Correct answer)
- When the pipeline pressure exceeds 60 psig
- When the vaporizer malfunctions
Correct answer: When the primary supply reaches a predetermined low-level setpoint
The reserve supply alarm activates when the primary liquid oxygen supply drops to a pre-set low level, alerting staff to arrange resupply before the reserve is needed.
Question 7: A verifier finds that a zone valve for the oxygen system is labeled 'Medical Air' during final verification walk-through. What is the correct action?
- Accept the minor discrepancy and note it in the report
- Immediately stop all testing and require correction before proceeding (Correct answer)
- Relabel the valve without retesting
- Notify the facility only after the verification report is complete
Correct answer: Immediately stop all testing and require correction before proceeding
Incorrect zone valve labeling is a safety-critical finding that must be corrected before testing continues, as mislabeled valves can result in shutting off the wrong gas during an emergency.
RMGA System Testing 4
What type of gas must NOT be used to perform a pressure leak test on an oxidizer (oxygen or nitrous oxide) medical gas pipeline?