New Mexico (NM) JG Journeyman
Natural Gas Fitter Practice Exam |
Questions and Answers | 2026 Update |
100% Correct
1. A Journeyman Natural Gas Fitter in New Mexico is required to ensure that a natural
gas piping system operating at 5 psi inside a commercial kitchen is installed in
accordance with which primary code set?
A) International Fuel Gas Code (IFGC) as adopted by NM with state amendments
B) International Residential Code (IRC) only
C) Uniform Plumbing Code (UPC) without amendments
D) National Fuel Gas Code (NFPA 54) without local amendments
Answer: A
*Explanation: New Mexico adopts the International Fuel Gas Code (IFGC) with state-
specific amendments for commercial and residential gas fitting work. The IRC is limited
to residential, UPC is not the primary gas code, and NFPA 54 is largely harmonized with
IFGC but NM specifically adopts IFGC as its base code with amendments.*
2. When testing a new natural gas service line from the main to the meter set for
leakage, the minimum test pressure for a plastic service line operating below 10 psi is:
,A) 3 psi for 15 minutes
B) 10 psi for 30 minutes
C) 60 psi for 30 minutes
D) 100 psi for 60 minutes
Answer: C
*Explanation: For plastic pipe (typically polyethylene) used in natural gas distribution,
the code requires a pressure test of at least 60 psi for a minimum of 30 minutes, with no
pressure drop. Lower pressures are insufficient for detecting leaks in plastic joints; 100
psi is for higher-pressure systems or specific conditions.*
3. In New Mexico, a natural gas appliance connector (flexible connector) used for a
movable appliance such as a commercial range must not exceed what maximum length?
A) 3 feet
B) 4 feet
C) 6 feet
D) 8 feet
Answer: C
Explanation: IFGC and NM amendments limit an appliance connector for a movable
appliance to 6 feet. For stationary appliances, shorter lengths (3 ft) are typical, but
movable appliances may use up to 6 ft. Lengths beyond that require rigid piping.
4. The minimum burial depth for a natural gas polyethylene (PE) pipe installed under a
residential driveway in New Mexico, not subject to heavy truck loading, is:
A) 12 inches
B) 18 inches
,C) 24 inches
D) 30 inches
Answer: B
*Explanation: Under driveways and parking areas (residential), the minimum cover for PE
gas pipe is 18 inches. In non-trafficked areas it can be 12 inches, and under roads or
heavy truck loading it increases to 24-30 inches.*
5. A Journeyman Gas Fitter installs a gas line inside a concealed wall cavity. The line
must be protected from physical damage. Which of the following is an acceptable
method?
A) Wrapping the pipe with electrical tape
B) Installing a 16-gauge steel protective plate over the pipe
C) Using Schedule 10 black iron pipe without additional protection
D) Burying the pipe in spray foam insulation
Answer: B
*Explanation: Concealed gas piping requires protection from nails or screws. A steel
plate at least 1/16 inch thick (16 gauge) is an accepted method. Schedule 10 pipe is too
thin; electrical tape and spray foam provide no mechanical protection.*
6. When using a manometer to measure gas pressure at an appliance’s manifold, what is
the correct procedure if the appliance’s rated manifold pressure is 3.5 inches water
column (WC) for natural gas?
A) Adjust the appliance’s pressure regulator to 4.0 inches WC to compensate for
elevation in NM
B) Read pressure with appliance off and main gas cock open
, C) Measure with the appliance running and all other gas appliances in the building at
maximum demand
D) Measure with the appliance off and all other appliances off
Answer: C
Explanation: Manifold pressure must be checked with the appliance operating at full fire
and all other gas appliances on the system operating simultaneously to ensure proper
supply under load. This verifies the regulator can maintain rated pressure under maximum
demand.
7. In a New Mexico home, a natural gas fireplace with an input rating of 40,000 Btu/h is
installed. The existing gas line supplies 80,000 Btu/h total capacity. What minimum free
area of combustion air opening (from indoors) is required if using indoor air only?
A) 40 sq in
B) 80 sq in
C) 100 sq in
D) 200 sq in
Answer: A
*Explanation: For appliances drawing combustion air from indoors, the code requires 1
square inch per 1,000 Btu/h of appliance input. 40,000 Btu/h ÷ 1,000 = 40 sq in free
area.*
8. A gas fitter must install a sediment trap (drip leg) ahead of an appliance. Where is the
correct location?
A) At the appliance’s vent connection
B) At the lowest point of the gas piping system before the appliance connector
Natural Gas Fitter Practice Exam |
Questions and Answers | 2026 Update |
100% Correct
1. A Journeyman Natural Gas Fitter in New Mexico is required to ensure that a natural
gas piping system operating at 5 psi inside a commercial kitchen is installed in
accordance with which primary code set?
A) International Fuel Gas Code (IFGC) as adopted by NM with state amendments
B) International Residential Code (IRC) only
C) Uniform Plumbing Code (UPC) without amendments
D) National Fuel Gas Code (NFPA 54) without local amendments
Answer: A
*Explanation: New Mexico adopts the International Fuel Gas Code (IFGC) with state-
specific amendments for commercial and residential gas fitting work. The IRC is limited
to residential, UPC is not the primary gas code, and NFPA 54 is largely harmonized with
IFGC but NM specifically adopts IFGC as its base code with amendments.*
2. When testing a new natural gas service line from the main to the meter set for
leakage, the minimum test pressure for a plastic service line operating below 10 psi is:
,A) 3 psi for 15 minutes
B) 10 psi for 30 minutes
C) 60 psi for 30 minutes
D) 100 psi for 60 minutes
Answer: C
*Explanation: For plastic pipe (typically polyethylene) used in natural gas distribution,
the code requires a pressure test of at least 60 psi for a minimum of 30 minutes, with no
pressure drop. Lower pressures are insufficient for detecting leaks in plastic joints; 100
psi is for higher-pressure systems or specific conditions.*
3. In New Mexico, a natural gas appliance connector (flexible connector) used for a
movable appliance such as a commercial range must not exceed what maximum length?
A) 3 feet
B) 4 feet
C) 6 feet
D) 8 feet
Answer: C
Explanation: IFGC and NM amendments limit an appliance connector for a movable
appliance to 6 feet. For stationary appliances, shorter lengths (3 ft) are typical, but
movable appliances may use up to 6 ft. Lengths beyond that require rigid piping.
4. The minimum burial depth for a natural gas polyethylene (PE) pipe installed under a
residential driveway in New Mexico, not subject to heavy truck loading, is:
A) 12 inches
B) 18 inches
,C) 24 inches
D) 30 inches
Answer: B
*Explanation: Under driveways and parking areas (residential), the minimum cover for PE
gas pipe is 18 inches. In non-trafficked areas it can be 12 inches, and under roads or
heavy truck loading it increases to 24-30 inches.*
5. A Journeyman Gas Fitter installs a gas line inside a concealed wall cavity. The line
must be protected from physical damage. Which of the following is an acceptable
method?
A) Wrapping the pipe with electrical tape
B) Installing a 16-gauge steel protective plate over the pipe
C) Using Schedule 10 black iron pipe without additional protection
D) Burying the pipe in spray foam insulation
Answer: B
*Explanation: Concealed gas piping requires protection from nails or screws. A steel
plate at least 1/16 inch thick (16 gauge) is an accepted method. Schedule 10 pipe is too
thin; electrical tape and spray foam provide no mechanical protection.*
6. When using a manometer to measure gas pressure at an appliance’s manifold, what is
the correct procedure if the appliance’s rated manifold pressure is 3.5 inches water
column (WC) for natural gas?
A) Adjust the appliance’s pressure regulator to 4.0 inches WC to compensate for
elevation in NM
B) Read pressure with appliance off and main gas cock open
, C) Measure with the appliance running and all other gas appliances in the building at
maximum demand
D) Measure with the appliance off and all other appliances off
Answer: C
Explanation: Manifold pressure must be checked with the appliance operating at full fire
and all other gas appliances on the system operating simultaneously to ensure proper
supply under load. This verifies the regulator can maintain rated pressure under maximum
demand.
7. In a New Mexico home, a natural gas fireplace with an input rating of 40,000 Btu/h is
installed. The existing gas line supplies 80,000 Btu/h total capacity. What minimum free
area of combustion air opening (from indoors) is required if using indoor air only?
A) 40 sq in
B) 80 sq in
C) 100 sq in
D) 200 sq in
Answer: A
*Explanation: For appliances drawing combustion air from indoors, the code requires 1
square inch per 1,000 Btu/h of appliance input. 40,000 Btu/h ÷ 1,000 = 40 sq in free
area.*
8. A gas fitter must install a sediment trap (drip leg) ahead of an appliance. Where is the
correct location?
A) At the appliance’s vent connection
B) At the lowest point of the gas piping system before the appliance connector
