HYPERBARIC STUDY EXAM – SAFETY, NFPA, ASME,
UHMS-GRADED A
1. Considering hyperbaric safety, which of the following is NOT an ignition source of
concern?
A. Static electricity
B. Electrical equipment
C. Open flame
D. Petroleum products
CORRECT ANSWER: D. Petroleum products
Explanation: Petroleum products are classified as fuel sources, not ignition sources.
Ignition sources provide the energy needed to start combustion. In a hyperbaric
environment, oxygen concentration greatly increases fire risk when ignition sources are
present. Eliminating ignition sources is critical for chamber safety.
2. Which of the following is NOT required by NFPA 99?
A. Control of ignition sources
B. Limitation of electrical equipment
C. Garments made of 100% cotton
D. Fire prevention procedures
CORRECT ANSWER: C. Garments made of 100% cotton
Explanation: NFPA 99 allows cotton-polyester blends and does not require garments to
be 100% cotton. The focus is on reducing static electricity and flammability. Clothing
must meet safety requirements but does not have to be pure cotton. Proper garment
approval is facility-specific.
3. Before 1980, most chamber fires were caused by:
A. Static discharge
B. Patient clothing
C. Electrical sources
D. Oxygen leaks
CORRECT ANSWER: C. Electrical sources
Explanation: Older hyperbaric chambers had less stringent electrical standards. Faulty
wiring and non-approved equipment contributed to fires. Modern NFPA standards
significantly reduced this risk. Electrical controls are now strictly regulated.
4. According to NFPA 99, the maximum allowable temperature of equipment or electrical
circuits in any chamber is 140°F (60°C).
A. True
B. False
CORRECT ANSWER: B. False
Explanation: Operating surface temperatures in multiplace chambers are limited to
185°F (85°C). The stated 140°F limit is incorrect. Temperature limits exist to prevent
ignition in oxygen-rich environments. These limits vary based on equipment location and
chamber class.
,5. According to NFPA 99, which of the following is a limitation on electrical equipment
inside a Class B chamber?
A. Unlimited power usage
B. No monitoring equipment allowed
C. Limited to communications and physiologic monitoring
D. Battery-powered devices only
CORRECT ANSWER: C. Limited to communications and physiologic monitoring
Explanation: Class B chambers restrict electrical equipment to essential systems. This
minimizes ignition risk. Monitoring and communication devices must meet strict
approval standards. Nonessential equipment is prohibited.
6. According to NFPA 99, what is the power limitation on a communication system inside a
hyperbaric chamber?
A. 120 volts
B. 50 volts
C. No more than 28 volts
D. No limitation
CORRECT ANSWER: C. No more than 28 volts
Explanation: NFPA 99 limits communication systems to 28 volts. In multiplace
chambers, the limit is also 0.5 watts. These limits reduce the risk of sparks or
overheating. Both monoplace and multiplace chambers must comply.
7. The UHMS guidelines address:
A. Chamber construction standards
B. Fire suppression systems
C. Clinical practice of hyperbaric medicine
D. Electrical equipment approval
CORRECT ANSWER: C. Clinical practice of hyperbaric medicine
Explanation: UHMS focuses on medical indications and patient care. It does not
regulate chamber construction or electrical systems. Clinical protocols are based on
evidence-based medicine. UHMS guidelines are widely accepted in hyperbaric practice.
8. The acronym ASME stands for:
A. American Safety of Medical Equipment
B. American Society of Mechanical Engineers
C. Association of Safety Management Engineers
D. American Standards for Medical Equipment
CORRECT ANSWER: B. American Society of Mechanical Engineers
Explanation: ASME develops codes for mechanical systems and pressure vessels.
Hyperbaric chambers fall under these standards. ASME codes ensure structural safety.
Compliance is required for chamber certification.
9. The acronym PVHO stands for:
A. Pressurized Vessel Human Operation
B. Pressure Vessel Housing Occupants
C. Pressure Vessels for Human Occupancy
D. Pressurized Volume Holding Oxygen
CORRECT ANSWER: C. Pressure Vessels for Human Occupancy
Explanation: PVHO standards apply to vessels designed for people inside. Hyperbaric
, chambers are classified as PVHOs. These standards ensure occupant safety under
pressure. They address design, materials, and testing.
10. The ASME Boiler and Pressure Vessel Code addresses:
A. Medical gases only
B. Hyperbaric chambers only
C. Steam boilers, diving bells, and pressure vessels
D. Electrical safety systems
CORRECT ANSWER: C. Steam boilers, diving bells, and pressure vessels
Explanation: The ASME code covers many pressurized systems. Hyperbaric chambers
are included as pressure vessels. These codes ensure safe operation under pressure.
Compliance is mandatory for certification.
11. ASME PVHO-2 is the newer edition of ASME PVHO-1.
A. True
B. False
CORRECT ANSWER: B. False
Explanation: PVHO-1 addresses design and construction of acrylic windows. PVHO-2
is a post-construction document. It focuses on inspection, maintenance, and service life.
The two documents serve different purposes.
12. What is a viewpoint?
A. A visual inspection procedure
B. A chamber monitoring device
C. An assembly including flange, seals, and acrylic window
D. A communication port
CORRECT ANSWER: C. An assembly including flange, seals, and acrylic window
Explanation: A viewpoint includes multiple components working together. It is not just
the acrylic window. Proper assembly is essential for pressure integrity. Viewpoints must
meet ASME PVHO standards.
13. According to ASME PVHO-2, how often should acrylics be inspected for scratches and
crazing?
A. Weekly
B. Monthly
C. Daily
D. Annually
CORRECT ANSWER: C. Daily
Explanation: Daily inspection helps detect early damage. Scratches and crazing weaken
acrylics. Early identification prevents catastrophic failure. This inspection is a routine
operational requirement.
14. According to ASME PVHO-2, how often should a maintenance inspection be performed
on acrylics?
A. Annually
B. Every 2–3 years
C. Every 5 years
D. Every 10 years
CORRECT ANSWER: B. Every 2–3 years
Explanation: Maintenance inspections are more detailed than daily checks. They assess
UHMS-GRADED A
1. Considering hyperbaric safety, which of the following is NOT an ignition source of
concern?
A. Static electricity
B. Electrical equipment
C. Open flame
D. Petroleum products
CORRECT ANSWER: D. Petroleum products
Explanation: Petroleum products are classified as fuel sources, not ignition sources.
Ignition sources provide the energy needed to start combustion. In a hyperbaric
environment, oxygen concentration greatly increases fire risk when ignition sources are
present. Eliminating ignition sources is critical for chamber safety.
2. Which of the following is NOT required by NFPA 99?
A. Control of ignition sources
B. Limitation of electrical equipment
C. Garments made of 100% cotton
D. Fire prevention procedures
CORRECT ANSWER: C. Garments made of 100% cotton
Explanation: NFPA 99 allows cotton-polyester blends and does not require garments to
be 100% cotton. The focus is on reducing static electricity and flammability. Clothing
must meet safety requirements but does not have to be pure cotton. Proper garment
approval is facility-specific.
3. Before 1980, most chamber fires were caused by:
A. Static discharge
B. Patient clothing
C. Electrical sources
D. Oxygen leaks
CORRECT ANSWER: C. Electrical sources
Explanation: Older hyperbaric chambers had less stringent electrical standards. Faulty
wiring and non-approved equipment contributed to fires. Modern NFPA standards
significantly reduced this risk. Electrical controls are now strictly regulated.
4. According to NFPA 99, the maximum allowable temperature of equipment or electrical
circuits in any chamber is 140°F (60°C).
A. True
B. False
CORRECT ANSWER: B. False
Explanation: Operating surface temperatures in multiplace chambers are limited to
185°F (85°C). The stated 140°F limit is incorrect. Temperature limits exist to prevent
ignition in oxygen-rich environments. These limits vary based on equipment location and
chamber class.
,5. According to NFPA 99, which of the following is a limitation on electrical equipment
inside a Class B chamber?
A. Unlimited power usage
B. No monitoring equipment allowed
C. Limited to communications and physiologic monitoring
D. Battery-powered devices only
CORRECT ANSWER: C. Limited to communications and physiologic monitoring
Explanation: Class B chambers restrict electrical equipment to essential systems. This
minimizes ignition risk. Monitoring and communication devices must meet strict
approval standards. Nonessential equipment is prohibited.
6. According to NFPA 99, what is the power limitation on a communication system inside a
hyperbaric chamber?
A. 120 volts
B. 50 volts
C. No more than 28 volts
D. No limitation
CORRECT ANSWER: C. No more than 28 volts
Explanation: NFPA 99 limits communication systems to 28 volts. In multiplace
chambers, the limit is also 0.5 watts. These limits reduce the risk of sparks or
overheating. Both monoplace and multiplace chambers must comply.
7. The UHMS guidelines address:
A. Chamber construction standards
B. Fire suppression systems
C. Clinical practice of hyperbaric medicine
D. Electrical equipment approval
CORRECT ANSWER: C. Clinical practice of hyperbaric medicine
Explanation: UHMS focuses on medical indications and patient care. It does not
regulate chamber construction or electrical systems. Clinical protocols are based on
evidence-based medicine. UHMS guidelines are widely accepted in hyperbaric practice.
8. The acronym ASME stands for:
A. American Safety of Medical Equipment
B. American Society of Mechanical Engineers
C. Association of Safety Management Engineers
D. American Standards for Medical Equipment
CORRECT ANSWER: B. American Society of Mechanical Engineers
Explanation: ASME develops codes for mechanical systems and pressure vessels.
Hyperbaric chambers fall under these standards. ASME codes ensure structural safety.
Compliance is required for chamber certification.
9. The acronym PVHO stands for:
A. Pressurized Vessel Human Operation
B. Pressure Vessel Housing Occupants
C. Pressure Vessels for Human Occupancy
D. Pressurized Volume Holding Oxygen
CORRECT ANSWER: C. Pressure Vessels for Human Occupancy
Explanation: PVHO standards apply to vessels designed for people inside. Hyperbaric
, chambers are classified as PVHOs. These standards ensure occupant safety under
pressure. They address design, materials, and testing.
10. The ASME Boiler and Pressure Vessel Code addresses:
A. Medical gases only
B. Hyperbaric chambers only
C. Steam boilers, diving bells, and pressure vessels
D. Electrical safety systems
CORRECT ANSWER: C. Steam boilers, diving bells, and pressure vessels
Explanation: The ASME code covers many pressurized systems. Hyperbaric chambers
are included as pressure vessels. These codes ensure safe operation under pressure.
Compliance is mandatory for certification.
11. ASME PVHO-2 is the newer edition of ASME PVHO-1.
A. True
B. False
CORRECT ANSWER: B. False
Explanation: PVHO-1 addresses design and construction of acrylic windows. PVHO-2
is a post-construction document. It focuses on inspection, maintenance, and service life.
The two documents serve different purposes.
12. What is a viewpoint?
A. A visual inspection procedure
B. A chamber monitoring device
C. An assembly including flange, seals, and acrylic window
D. A communication port
CORRECT ANSWER: C. An assembly including flange, seals, and acrylic window
Explanation: A viewpoint includes multiple components working together. It is not just
the acrylic window. Proper assembly is essential for pressure integrity. Viewpoints must
meet ASME PVHO standards.
13. According to ASME PVHO-2, how often should acrylics be inspected for scratches and
crazing?
A. Weekly
B. Monthly
C. Daily
D. Annually
CORRECT ANSWER: C. Daily
Explanation: Daily inspection helps detect early damage. Scratches and crazing weaken
acrylics. Early identification prevents catastrophic failure. This inspection is a routine
operational requirement.
14. According to ASME PVHO-2, how often should a maintenance inspection be performed
on acrylics?
A. Annually
B. Every 2–3 years
C. Every 5 years
D. Every 10 years
CORRECT ANSWER: B. Every 2–3 years
Explanation: Maintenance inspections are more detailed than daily checks. They assess
