NFPA 99 6040 practice set Most Recent exam COMPLETE (2026) EXAM
Questions and Answers (Verified Answers) (Latest Update 2) Graded A+
NFPA 99 Chapter 6 Practice Questions —)
1. Which gas in a hospital must have a reserve supply capacity per NFPA 99?
A) Medical air
B) Nitrous oxide
C) Oxygen
D) Nitrogen
Rationale: Oxygen systems typically require a reserve supply to maintain continuity of
patient care.
2. What is the maximum allowable pressure drop, per NFPA 99, from the source to the
farthest outlet in a medical gas pipeline?
A) 5 psig
B) 10 psig
C) 20 psig
D) 30 psig
Rationale: Keeping pressure drop within correct limits ensures adequate pressure at the
outlet.
3. According to NFPA 99, medical oxygen cylinder color (U.S. standard) is:
A) Green
B) Blue
C) White or white-green
D) Black
Rationale: NFPA references standard cylinder color coding; in the U.S., oxygen is often
white or white-green.
4. NFPA 99 requires that gas piping wall thickness be capable of withstanding:
A) Only room temperature pressure
B) Internal pressure consistent with system design (using ASME/ANSI standards)
C) No pressure test required
D) Only vacuum
1
Page
EXAMPREPMASTER
, Rationale: Piping must be rated per mechanical pressure-rating standards to ensure
safety.
5. Which of these must vacuum (suction) systems comply with, per NFPA 99?
A) Positive pressure only
B) Maintain a specified vacuum (negative) level at outlets
C) Must only serve one room
D) Require no alarms
Rationale: Vacuum systems must sustain a design vacuum (negative pressure) to
function properly in patient care.
6. What device does NFPA 99 typically require to prevent backflow in medical gas
systems?
A) Flow restrictor
B) Check valve (or back-pressure regulator)
C) One-way bleed valve only
D) None required
Rationale: Check valves or back-pressure regulators prevent backflow, preserving purity
and safety.
7. What is required after the installation of medical gas piping before being placed into
service, according to NFPA 99?
A) Visual inspection only
B) Pressure-leak test (pneumatic or hydrostatic)
C) Flow-rate testing only
D) No testing
Rationale: A pressure test confirms integrity of the piping system.
8. Under NFPA 99, how must each medical gas outlet be labeled?
A) Color only
B) Gas name and pressure class
C) Just “MED GAS”
D) Manufacturer name only
Rationale: Text labeling plus color enhances clarity and prevents misconnections.
9. Which alarm(s) are required by NFPA 99 in a medical gas central system?
A) High-pressure only
B) High- and low-pressure alarms
C) Low-pressure only
D) No alarms if there is backup
2
Page
EXAMPREPMASTER
, Rationale: Both high and low pressure alarms are necessary for safe operating range
monitoring.
10. Why does NFPA 99 require filtration on medical air compressors?
A) To warm the air
B) To remove particles, oil, and moisture
C) To color the gas
D) To reduce odor
Rationale: Filtration keeps the medical air safe and clean for patient inhalation.
11. True or False: NFPA 99 permits using non-oxygen-compatible lubricants in oxygen
system joints.
A) False
B) True
Rationale: Only oxygen-compatible lubricants may be used; incompatible ones may
cause fire or explosion.
12. How often does NFPA 99 recommend testing gas system alarms?
A) Monthly
B) Quarterly
C) Every two years
D) Only after installation
Rationale: Regular (quarterly) testing ensures alarm reliability and performance.
13. Which document is required onsite for medical gas systems as per NFPA 99?
A) Employee roster
B) Piping and Instrumentation Diagram (P&ID)
C) Marketing manual
D) Financial statements
Rationale: A P&ID provides critical layout, valve, and system information for
maintenance and emergencies.
14. In risk assessment for medical gas systems, NFPA 99 mandates consideration of:
A) Sales projections
B) Contamination, backflow, and system failure risk
C) Staffing ratios
D) Marketing strategy
Rationale: Technical and safety risks must be identified and mitigated in system design.
3
15. A hospital is installing a new central vacuum system. According to NFPA 99, the
Page
design should include:
EXAMPREPMASTER
Questions and Answers (Verified Answers) (Latest Update 2) Graded A+
NFPA 99 Chapter 6 Practice Questions —)
1. Which gas in a hospital must have a reserve supply capacity per NFPA 99?
A) Medical air
B) Nitrous oxide
C) Oxygen
D) Nitrogen
Rationale: Oxygen systems typically require a reserve supply to maintain continuity of
patient care.
2. What is the maximum allowable pressure drop, per NFPA 99, from the source to the
farthest outlet in a medical gas pipeline?
A) 5 psig
B) 10 psig
C) 20 psig
D) 30 psig
Rationale: Keeping pressure drop within correct limits ensures adequate pressure at the
outlet.
3. According to NFPA 99, medical oxygen cylinder color (U.S. standard) is:
A) Green
B) Blue
C) White or white-green
D) Black
Rationale: NFPA references standard cylinder color coding; in the U.S., oxygen is often
white or white-green.
4. NFPA 99 requires that gas piping wall thickness be capable of withstanding:
A) Only room temperature pressure
B) Internal pressure consistent with system design (using ASME/ANSI standards)
C) No pressure test required
D) Only vacuum
1
Page
EXAMPREPMASTER
, Rationale: Piping must be rated per mechanical pressure-rating standards to ensure
safety.
5. Which of these must vacuum (suction) systems comply with, per NFPA 99?
A) Positive pressure only
B) Maintain a specified vacuum (negative) level at outlets
C) Must only serve one room
D) Require no alarms
Rationale: Vacuum systems must sustain a design vacuum (negative pressure) to
function properly in patient care.
6. What device does NFPA 99 typically require to prevent backflow in medical gas
systems?
A) Flow restrictor
B) Check valve (or back-pressure regulator)
C) One-way bleed valve only
D) None required
Rationale: Check valves or back-pressure regulators prevent backflow, preserving purity
and safety.
7. What is required after the installation of medical gas piping before being placed into
service, according to NFPA 99?
A) Visual inspection only
B) Pressure-leak test (pneumatic or hydrostatic)
C) Flow-rate testing only
D) No testing
Rationale: A pressure test confirms integrity of the piping system.
8. Under NFPA 99, how must each medical gas outlet be labeled?
A) Color only
B) Gas name and pressure class
C) Just “MED GAS”
D) Manufacturer name only
Rationale: Text labeling plus color enhances clarity and prevents misconnections.
9. Which alarm(s) are required by NFPA 99 in a medical gas central system?
A) High-pressure only
B) High- and low-pressure alarms
C) Low-pressure only
D) No alarms if there is backup
2
Page
EXAMPREPMASTER
, Rationale: Both high and low pressure alarms are necessary for safe operating range
monitoring.
10. Why does NFPA 99 require filtration on medical air compressors?
A) To warm the air
B) To remove particles, oil, and moisture
C) To color the gas
D) To reduce odor
Rationale: Filtration keeps the medical air safe and clean for patient inhalation.
11. True or False: NFPA 99 permits using non-oxygen-compatible lubricants in oxygen
system joints.
A) False
B) True
Rationale: Only oxygen-compatible lubricants may be used; incompatible ones may
cause fire or explosion.
12. How often does NFPA 99 recommend testing gas system alarms?
A) Monthly
B) Quarterly
C) Every two years
D) Only after installation
Rationale: Regular (quarterly) testing ensures alarm reliability and performance.
13. Which document is required onsite for medical gas systems as per NFPA 99?
A) Employee roster
B) Piping and Instrumentation Diagram (P&ID)
C) Marketing manual
D) Financial statements
Rationale: A P&ID provides critical layout, valve, and system information for
maintenance and emergencies.
14. In risk assessment for medical gas systems, NFPA 99 mandates consideration of:
A) Sales projections
B) Contamination, backflow, and system failure risk
C) Staffing ratios
D) Marketing strategy
Rationale: Technical and safety risks must be identified and mitigated in system design.
3
15. A hospital is installing a new central vacuum system. According to NFPA 99, the
Page
design should include:
EXAMPREPMASTER
