Maryland (MD) Master Natural Gas Fitter Practice Exam
Question 1:
Which of the following materials is most commonly used for residential natural gas piping?
A) Copper
B) PVC
C) Black steel
D) Cast iron
Correct Answer: C
Explanation: Black steel is favored for its strength, durability, and compatibility with natural gas.
Question 2:
When designing a natural gas piping system, the layout should primarily aim to:
A) Maximize aesthetic appeal
B) Minimize pipe length to reduce pressure loss
C) Use the lightest material available
D) Increase the number of fittings for flexibility
Correct Answer: B
Explanation: Shorter pipe runs help reduce friction and pressure loss, ensuring efficient gas delivery.
Question 3:
Which document is essential for ensuring that a natural gas piping system meets current safety
standards?
A) The National Electrical Code
B) The International Fuel Gas Code
C) The Residential Plumbing Code
D) The Mechanical Engineering Handbook
Correct Answer: B
Explanation: The International Fuel Gas Code (IFGC) provides comprehensive guidelines for safe gas
system installation.
Question 4:
During installation, pipe joints must be:
A) Loosely connected for future adjustments
B) Sealed to prevent gas leaks
C) Painted for corrosion resistance only
D) Oversized to allow extra fittings
Correct Answer: B
Explanation: Proper sealing of joints is critical to prevent gas leaks and ensure system safety.
Question 5:
What is the primary reason for using a pressure test on a newly installed gas piping system?
A) To calibrate gas meters
B) To check for leaks and system integrity
C) To measure gas quality
,D) To adjust appliance settings
Correct Answer: B
Explanation: Pressure tests help verify that the system is leak-free and can safely operate under working
pressure.
Question 6:
Which factor is least important when selecting piping materials for natural gas?
A) Chemical compatibility
B) Mechanical strength
C) Color of the pipe
D) Corrosion resistance
Correct Answer: C
Explanation: While aesthetics can be a concern in some applications, the performance factors are
paramount.
Question 7:
What is the primary function of pipe supports and hangers in a gas piping system?
A) To enhance the visual appeal
B) To ensure proper alignment and prevent sagging
C) To increase pressure
D) To simplify future modifications
Correct Answer: B
Explanation: Supports and hangers keep the piping securely in place and prevent mechanical stress.
Question 8:
Which of the following is a common cause of failure in improperly installed gas piping systems?
A) Excessive heat exposure
B) Incorrect pipe sizing
C) Over-painting of pipes
D) Use of flexible materials
Correct Answer: B
Explanation: Incorrect sizing can lead to inadequate gas flow or excessive pressure drops.
Question 9:
In a residential gas system design, why is it important to plan for future appliance additions?
A) To reduce current installation costs
B) To avoid major system modifications later
C) To use up extra piping
D) To simplify the color-coding of pipes
Correct Answer: B
Explanation: Designing with future expansion in mind minimizes the need for extensive retrofits.
Question 10:
Which practice is recommended when routing gas pipes in a building?
A) Running pipes near electrical conduits
B) Keeping pipes accessible for inspection and maintenance
C) Concealing pipes behind permanent structures
,D) Using unsupported long pipe runs
Correct Answer: B
Explanation: Accessibility is key for periodic inspections and maintenance tasks.
Question 11:
The installation of gas piping must comply with which type of codes?
A) Electrical codes only
B) Local, state, and national gas codes
C) Automotive codes
D) General building codes only
Correct Answer: B
Explanation: Compliance with all applicable codes ensures safety and regulatory adherence.
Question 12:
A primary benefit of using rigid piping materials in gas systems is:
A) Greater flexibility for movement
B) Reduced risk of damage and deformation
C) Lower cost compared to flexible pipes
D) Easier installation around corners
Correct Answer: B
Explanation: Rigid pipes maintain their shape under pressure, reducing the risk of deformation.
Question 13:
When planning the routing of gas piping, what must be considered regarding nearby combustible
materials?
A) They should be painted the same color
B) They must be located at a safe distance
C) They must be insulated
D) They are irrelevant to gas piping safety
Correct Answer: B
Explanation: Maintaining safe clearances from combustibles prevents fire hazards.
Question 14:
Which of the following best describes “trunk and branch” system in gas piping?
A) A decorative design approach
B) A method where a main line (trunk) feeds multiple secondary lines (branches)
C) A technique for mixing gas types
D) A method for temporary installations
Correct Answer: B
Explanation: This system design efficiently distributes gas from a main supply line to various appliances.
Question 15:
In natural gas piping systems, what is the role of a regulator?
A) To increase gas pressure for high-demand appliances
B) To decrease and stabilize gas pressure
C) To filter impurities from the gas
D) To automatically shut off gas during a leak
, Correct Answer: B
Explanation: Regulators adjust the incoming pressure to a safe, usable level for appliances.
Question 16:
Which of the following is a key consideration during the installation of gas piping systems in new
construction?
A) Scheduling painting of the pipes
B) Coordinating with other trades to avoid conflicts
C) Installing pipes after drywall is complete
D) Using the most expensive fittings available
Correct Answer: B
Explanation: Coordination ensures that piping is installed safely and does not interfere with other
systems.
Question 17:
How does proper pipe sizing contribute to system performance?
A) It increases the overall gas consumption
B) It minimizes pressure drop and ensures efficient gas flow
C) It makes the installation more complicated
D) It allows for the use of thinner insulation
Correct Answer: B
Explanation: Correct sizing ensures that gas reaches appliances at the proper pressure.
Question 18:
What is one of the main benefits of using flexible gas piping (when approved) in certain installations?
A) Increased durability
B) Easier installation in tight or irregular spaces
C) Higher resistance to corrosion
D) Lower risk of gas leaks
Correct Answer: B
Explanation: Flexibility can simplify installation where rigid piping would be difficult to run.
Question 19:
Which inspection is most critical immediately after the installation of a gas piping system?
A) Visual inspection only
B) A pressure (leak) test
C) Thermal imaging inspection
D) Vibration analysis
Correct Answer: B
Explanation: Pressure tests are vital to confirm the integrity of the system and detect leaks.
Question 20:
What should be verified before beginning the installation of gas piping?
A) The building’s interior design plan
B) The proper permits and code requirements
C) The availability of decorative finishes
D) The number of windows in the area
Question 1:
Which of the following materials is most commonly used for residential natural gas piping?
A) Copper
B) PVC
C) Black steel
D) Cast iron
Correct Answer: C
Explanation: Black steel is favored for its strength, durability, and compatibility with natural gas.
Question 2:
When designing a natural gas piping system, the layout should primarily aim to:
A) Maximize aesthetic appeal
B) Minimize pipe length to reduce pressure loss
C) Use the lightest material available
D) Increase the number of fittings for flexibility
Correct Answer: B
Explanation: Shorter pipe runs help reduce friction and pressure loss, ensuring efficient gas delivery.
Question 3:
Which document is essential for ensuring that a natural gas piping system meets current safety
standards?
A) The National Electrical Code
B) The International Fuel Gas Code
C) The Residential Plumbing Code
D) The Mechanical Engineering Handbook
Correct Answer: B
Explanation: The International Fuel Gas Code (IFGC) provides comprehensive guidelines for safe gas
system installation.
Question 4:
During installation, pipe joints must be:
A) Loosely connected for future adjustments
B) Sealed to prevent gas leaks
C) Painted for corrosion resistance only
D) Oversized to allow extra fittings
Correct Answer: B
Explanation: Proper sealing of joints is critical to prevent gas leaks and ensure system safety.
Question 5:
What is the primary reason for using a pressure test on a newly installed gas piping system?
A) To calibrate gas meters
B) To check for leaks and system integrity
C) To measure gas quality
,D) To adjust appliance settings
Correct Answer: B
Explanation: Pressure tests help verify that the system is leak-free and can safely operate under working
pressure.
Question 6:
Which factor is least important when selecting piping materials for natural gas?
A) Chemical compatibility
B) Mechanical strength
C) Color of the pipe
D) Corrosion resistance
Correct Answer: C
Explanation: While aesthetics can be a concern in some applications, the performance factors are
paramount.
Question 7:
What is the primary function of pipe supports and hangers in a gas piping system?
A) To enhance the visual appeal
B) To ensure proper alignment and prevent sagging
C) To increase pressure
D) To simplify future modifications
Correct Answer: B
Explanation: Supports and hangers keep the piping securely in place and prevent mechanical stress.
Question 8:
Which of the following is a common cause of failure in improperly installed gas piping systems?
A) Excessive heat exposure
B) Incorrect pipe sizing
C) Over-painting of pipes
D) Use of flexible materials
Correct Answer: B
Explanation: Incorrect sizing can lead to inadequate gas flow or excessive pressure drops.
Question 9:
In a residential gas system design, why is it important to plan for future appliance additions?
A) To reduce current installation costs
B) To avoid major system modifications later
C) To use up extra piping
D) To simplify the color-coding of pipes
Correct Answer: B
Explanation: Designing with future expansion in mind minimizes the need for extensive retrofits.
Question 10:
Which practice is recommended when routing gas pipes in a building?
A) Running pipes near electrical conduits
B) Keeping pipes accessible for inspection and maintenance
C) Concealing pipes behind permanent structures
,D) Using unsupported long pipe runs
Correct Answer: B
Explanation: Accessibility is key for periodic inspections and maintenance tasks.
Question 11:
The installation of gas piping must comply with which type of codes?
A) Electrical codes only
B) Local, state, and national gas codes
C) Automotive codes
D) General building codes only
Correct Answer: B
Explanation: Compliance with all applicable codes ensures safety and regulatory adherence.
Question 12:
A primary benefit of using rigid piping materials in gas systems is:
A) Greater flexibility for movement
B) Reduced risk of damage and deformation
C) Lower cost compared to flexible pipes
D) Easier installation around corners
Correct Answer: B
Explanation: Rigid pipes maintain their shape under pressure, reducing the risk of deformation.
Question 13:
When planning the routing of gas piping, what must be considered regarding nearby combustible
materials?
A) They should be painted the same color
B) They must be located at a safe distance
C) They must be insulated
D) They are irrelevant to gas piping safety
Correct Answer: B
Explanation: Maintaining safe clearances from combustibles prevents fire hazards.
Question 14:
Which of the following best describes “trunk and branch” system in gas piping?
A) A decorative design approach
B) A method where a main line (trunk) feeds multiple secondary lines (branches)
C) A technique for mixing gas types
D) A method for temporary installations
Correct Answer: B
Explanation: This system design efficiently distributes gas from a main supply line to various appliances.
Question 15:
In natural gas piping systems, what is the role of a regulator?
A) To increase gas pressure for high-demand appliances
B) To decrease and stabilize gas pressure
C) To filter impurities from the gas
D) To automatically shut off gas during a leak
, Correct Answer: B
Explanation: Regulators adjust the incoming pressure to a safe, usable level for appliances.
Question 16:
Which of the following is a key consideration during the installation of gas piping systems in new
construction?
A) Scheduling painting of the pipes
B) Coordinating with other trades to avoid conflicts
C) Installing pipes after drywall is complete
D) Using the most expensive fittings available
Correct Answer: B
Explanation: Coordination ensures that piping is installed safely and does not interfere with other
systems.
Question 17:
How does proper pipe sizing contribute to system performance?
A) It increases the overall gas consumption
B) It minimizes pressure drop and ensures efficient gas flow
C) It makes the installation more complicated
D) It allows for the use of thinner insulation
Correct Answer: B
Explanation: Correct sizing ensures that gas reaches appliances at the proper pressure.
Question 18:
What is one of the main benefits of using flexible gas piping (when approved) in certain installations?
A) Increased durability
B) Easier installation in tight or irregular spaces
C) Higher resistance to corrosion
D) Lower risk of gas leaks
Correct Answer: B
Explanation: Flexibility can simplify installation where rigid piping would be difficult to run.
Question 19:
Which inspection is most critical immediately after the installation of a gas piping system?
A) Visual inspection only
B) A pressure (leak) test
C) Thermal imaging inspection
D) Vibration analysis
Correct Answer: B
Explanation: Pressure tests are vital to confirm the integrity of the system and detect leaks.
Question 20:
What should be verified before beginning the installation of gas piping?
A) The building’s interior design plan
B) The proper permits and code requirements
C) The availability of decorative finishes
D) The number of windows in the area
