G2 EXAM PREP QUESTIONS AND
ANSWERS WITH COMPLETE
SOLUTIONS 100% CORRECT RATED A+
||UPDATED 2026
The best tool for adjusting and setting the pressure on an appliance regulator:
a. Manometer ✔✔ b. Velometer c. Psychrometer d. An analyzer
Answer: a. Manometer ✔✔
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A 3/8-inch NPS black iron pipe shall:
a. Not be used for propane b. Not be used in a concealed location ✔✔ c. Not be
used for natural gas d. Not be used indoors
Answer: b. Not be used in a concealed location ✔✔
═════════════════════════════════════════════
A corrugated metal flexible gas connector attached to a range cannot exceed
what length?
a. 6 ft ✔✔ b. 5 ft c. 3 ft d. 4 ft
Answer: a. 6 ft ✔✔
═════════════════════════════════════════════
Where must an individual manual gas shut-off valve be located?
a. Only on natural gas appliances b. In either the drop or riser supplying a
residential appliance ✔✔ c. Downstream of the piping union d. Directly at the drip
pocket
Answer: b. In either the drop or riser supplying a residential appliance ✔✔
Black iron pipe 2 1/2 NPS at 150' long shall be pressure tested to?
a. The greater of 50psig or 1.5 times the maximum operation pressure for 180
minutes
b. 50 psig for 180 minutes
c. 1.5 times the maximum operation pressure for 180 minutes
d. 50 psig for 60 minutes -ANSWER ✔✔50 psig for 60 minutes (Table 6.3)
Buried piping or tubing shall be?
a. only copper type L coated, type G coated, type K uncoated
,b. only copper type K, L or type G
c. schedule 50 ASTM A-53
d. only copper type L or G coated -ANSWER ✔✔Only copper type L coated, type
G coated, type K uncoated (6.2.7)
What is pressure drop?
a. The difference in the static pressure at the meter, and the working pressure at the
appliance regulator
b. The difference between the U tube manometer is the end that is open to the
atmosphere and the pressurized side when the appliance regulator is working
c. The difference between supply pressure and appliance manifold pressure when
the appliance calls for heat
d. The difference in the working pressure at the gas meter, and the working
pressure at the appliance regulator -ANSWER ✔✔The difference in the working
pressure at the gas meter, and the working pressure at the appliance regulator
Fittings used for steel piping may be made from?
a. brass or iron
b. copper to malleable iron
c. steel and plastic
d. malleable iron and steel -ANSWER ✔✔Malleable iron and steel (6.2.2)
Posts protecting piping and tubing entering a building from vehicular damage shall
be?
a. clearly marked and identified with yellow paint
b. Be spaced not more than 48" apart
c. Buried not less than 36" below grade
d. Made from 6x6 pressure treated wood -ANSWER ✔✔Buried not less than 36"
below grade
(6.16.15)
The equivalent length of a 2 1/2 NPS forged tee is?
a. 9.25'
b. 12.4'
c. 15.3'
,d. 10.3' -ANSWER ✔✔9.25' (Table A 16)
What is the maximum horizontal spacing of supports for N.P.S. 1 1/4 inch gas
pipe?
a. 8'
b. 15'
c. 6'
d. 10' -ANSWER ✔✔10' (3m) (Table 6.2)
When gas piping enters a building, it must?
a. Enter above grade
b. Be taped, painted, and sleeved
c. Have a tracer wire
d. Enter below grade -ANSWER ✔✔Enter above grade (6.15.8)
When sizing a branch line, what is the minimum size of job fabricated welding
fittings that can be used on a NPS 6 gas supply header?
a. 2" NPS
b. 3/4" NPS
c. 3" NPS
d. 1/2" NPS -ANSWER ✔✔3/4" NPS (6.8.8)
A dirt pockets shall be installed at the bottom of any piping or tubing, on the final
drop serving an appliance other than a(n)
a. Unit Heater
b. Furnace
c. Clothes dryer
d. Boiler -ANSWER ✔✔Clothes dryer (6.13.1)
Direct-vent wall furnace shall use what maximum length of corrugated metal gas
connector?
a. 6 ft.
b. 4 ft.
c. 8 ft.
, d. 2 ft. -ANSWER ✔✔2 ft. (6.21.3(c))
Every gas hose and gas fitting shall have a minimum working pressure of what.
a. 275 PSIG minimum or the setting of the hydrostatic relief valves.
b. 350 PSIG for piping and tubing operating at a container.
c. 350 PSIG
d. 250 PSIG when connected to the outlet of a pump or compressor. -ANSWER
✔✔350 PSIG (6.2.9)
What are the requirements for back filling underground piping or tubing?
a. It shall not have stones larger than 38 mm
b. The fill material shall contain no sharp objects.
c. A trench must be dug 15 inches deep
d. All of the choices -ANSWER ✔✔The fill material shall contain no sharp objects
(6.15.6)
Question 17
What is the approximate purging time for NPS 1 that is 40 feet in length?
a. 7 Seconds
b. 28 Seconds
c. 14 Seconds
d. 43 Seconds -ANSWER ✔✔28 seconds (Annex H Table H.1)
What is the maximum distance a readily accessible manual shut-off valve may be
installed from an appliance?
a. 2 ft. and identified
b. 10 ft. and identified
c. 25 ft. and identified
d. 50 ft. and identified -ANSWER ✔✔50 ft. and identified (6.18.2(d))
What is the minimum unthreaded portion of a piping outlet required when
installing a gas piping through a floor for a range?
a. 2 Inches
b. 6 Inches
ANSWERS WITH COMPLETE
SOLUTIONS 100% CORRECT RATED A+
||UPDATED 2026
The best tool for adjusting and setting the pressure on an appliance regulator:
a. Manometer ✔✔ b. Velometer c. Psychrometer d. An analyzer
Answer: a. Manometer ✔✔
═════════════════════════════════════════════
A 3/8-inch NPS black iron pipe shall:
a. Not be used for propane b. Not be used in a concealed location ✔✔ c. Not be
used for natural gas d. Not be used indoors
Answer: b. Not be used in a concealed location ✔✔
═════════════════════════════════════════════
A corrugated metal flexible gas connector attached to a range cannot exceed
what length?
a. 6 ft ✔✔ b. 5 ft c. 3 ft d. 4 ft
Answer: a. 6 ft ✔✔
═════════════════════════════════════════════
Where must an individual manual gas shut-off valve be located?
a. Only on natural gas appliances b. In either the drop or riser supplying a
residential appliance ✔✔ c. Downstream of the piping union d. Directly at the drip
Answer: b. In either the drop or riser supplying a residential appliance ✔✔
Black iron pipe 2 1/2 NPS at 150' long shall be pressure tested to?
a. The greater of 50psig or 1.5 times the maximum operation pressure for 180
minutes
b. 50 psig for 180 minutes
c. 1.5 times the maximum operation pressure for 180 minutes
d. 50 psig for 60 minutes -ANSWER ✔✔50 psig for 60 minutes (Table 6.3)
Buried piping or tubing shall be?
a. only copper type L coated, type G coated, type K uncoated
,b. only copper type K, L or type G
c. schedule 50 ASTM A-53
d. only copper type L or G coated -ANSWER ✔✔Only copper type L coated, type
G coated, type K uncoated (6.2.7)
What is pressure drop?
a. The difference in the static pressure at the meter, and the working pressure at the
appliance regulator
b. The difference between the U tube manometer is the end that is open to the
atmosphere and the pressurized side when the appliance regulator is working
c. The difference between supply pressure and appliance manifold pressure when
the appliance calls for heat
d. The difference in the working pressure at the gas meter, and the working
pressure at the appliance regulator -ANSWER ✔✔The difference in the working
pressure at the gas meter, and the working pressure at the appliance regulator
Fittings used for steel piping may be made from?
a. brass or iron
b. copper to malleable iron
c. steel and plastic
d. malleable iron and steel -ANSWER ✔✔Malleable iron and steel (6.2.2)
Posts protecting piping and tubing entering a building from vehicular damage shall
be?
a. clearly marked and identified with yellow paint
b. Be spaced not more than 48" apart
c. Buried not less than 36" below grade
d. Made from 6x6 pressure treated wood -ANSWER ✔✔Buried not less than 36"
below grade
(6.16.15)
The equivalent length of a 2 1/2 NPS forged tee is?
a. 9.25'
b. 12.4'
c. 15.3'
,d. 10.3' -ANSWER ✔✔9.25' (Table A 16)
What is the maximum horizontal spacing of supports for N.P.S. 1 1/4 inch gas
pipe?
a. 8'
b. 15'
c. 6'
d. 10' -ANSWER ✔✔10' (3m) (Table 6.2)
When gas piping enters a building, it must?
a. Enter above grade
b. Be taped, painted, and sleeved
c. Have a tracer wire
d. Enter below grade -ANSWER ✔✔Enter above grade (6.15.8)
When sizing a branch line, what is the minimum size of job fabricated welding
fittings that can be used on a NPS 6 gas supply header?
a. 2" NPS
b. 3/4" NPS
c. 3" NPS
d. 1/2" NPS -ANSWER ✔✔3/4" NPS (6.8.8)
A dirt pockets shall be installed at the bottom of any piping or tubing, on the final
drop serving an appliance other than a(n)
a. Unit Heater
b. Furnace
c. Clothes dryer
d. Boiler -ANSWER ✔✔Clothes dryer (6.13.1)
Direct-vent wall furnace shall use what maximum length of corrugated metal gas
connector?
a. 6 ft.
b. 4 ft.
c. 8 ft.
, d. 2 ft. -ANSWER ✔✔2 ft. (6.21.3(c))
Every gas hose and gas fitting shall have a minimum working pressure of what.
a. 275 PSIG minimum or the setting of the hydrostatic relief valves.
b. 350 PSIG for piping and tubing operating at a container.
c. 350 PSIG
d. 250 PSIG when connected to the outlet of a pump or compressor. -ANSWER
✔✔350 PSIG (6.2.9)
What are the requirements for back filling underground piping or tubing?
a. It shall not have stones larger than 38 mm
b. The fill material shall contain no sharp objects.
c. A trench must be dug 15 inches deep
d. All of the choices -ANSWER ✔✔The fill material shall contain no sharp objects
(6.15.6)
Question 17
What is the approximate purging time for NPS 1 that is 40 feet in length?
a. 7 Seconds
b. 28 Seconds
c. 14 Seconds
d. 43 Seconds -ANSWER ✔✔28 seconds (Annex H Table H.1)
What is the maximum distance a readily accessible manual shut-off valve may be
installed from an appliance?
a. 2 ft. and identified
b. 10 ft. and identified
c. 25 ft. and identified
d. 50 ft. and identified -ANSWER ✔✔50 ft. and identified (6.18.2(d))
What is the minimum unthreaded portion of a piping outlet required when
installing a gas piping through a floor for a range?
a. 2 Inches
b. 6 Inches
