Massachusetts (MA) Master Gas Fitter
Practice Exam Questions And Answers
Rated A+ New Update Assured
Satisfaction
1. A gas piping system in a commercial building in Massachusetts must be tested with
air or inert gas at a minimum pressure of:
a) 3 psi for 30 minutes
b) 10 psi for 60 minutes
c) 15 psi for 60 minutes
d) 100 psi for 24 hours
Answer: b) 10 psi for 60 minutes
Explanation: According to 248 CMR 5.00 and NFPA 54, the MA amendment requires a
pressure test of at least 10 psi (69 kPa) for 60 minutes with no measurable drop when
using air or an inert gas. The test must be performed before the system is covered or
concealed.
2. When sizing a natural gas line from a 2 psig service to a building, the allowable
pressure drop from the meter to the furthest appliance is typically:
a) 0.3 in. w.c.
b) 0.5 in. w.c.
c) 1.0 in. w.c.
d) 2.0 in. w.c.
Answer: c) 1.0 in. w.c.
Explanation: For systems operating at 2 psig with a line pressure regulator at each
,appliance, NFPA 54 allows a 1 psi drop on the high side, but the low-pressure side after
the regulator is limited to 1.0 in. w.c. drop for design purposes in MA.
3. A manual shutoff valve for a gas appliance installed in a residential garage in MA
must be located:
a) Inside the garage within 6 ft of the appliance
b) Outside the garage or within 6 ft of the appliance but not less than 3 ft above the
floor
c) At the meter only
d) Anywhere as long as it is accessible
Answer: b) Outside the garage or within 6 ft of the appliance but not less than 3 ft
above the floor
Explanation: MA amendments to NFPA 54 require garage appliance shutoffs to be
placed where they are not subject to physical damage and at least 3 ft above the garage
floor to avoid ignition of gasoline vapors.
4. A gas fitter in MA is required to have a license classification that allows work on
systems up to:
a) 250,000 Btu/hr without inspection
b) Any size if working under a master
c) Unlimited size only with a Master Gas Fitter license
d) 2 million Btu/hr with a Journeyman license
Answer: c) Unlimited size only with a Master Gas Fitter license
Explanation: Only a Master Gas Fitter license holder in MA may design, install, and
contract for gas piping and appliances of any size without supervision. Journeyman
must work under a Master.
5. The minimum burial depth for a plastic natural gas service line under a driveway in
MA is:
a) 12 in.
b) 18 in.
,c) 24 in.
d) 36 in.
Answer: c) 24 in.
Explanation: 248 CMR specifies 24 inches for plastic pipe under driveways and parking
areas, 18 inches under roads, and 12 inches under non-traffic areas, but the stricter
depth for driveways is 24 inches.
6. A CSST (corrugated stainless steel tubing) bonding requirement in MA mandates that
the CSST be bonded to the:
a) Neutral bus in the main panel
b) Grounding electrode system with a minimum 6 AWG copper conductor
c) Gas meter housing only
d) Water pipe within 5 ft of entry
Answer: b) Grounding electrode system with a minimum 6 AWG copper conductor
Explanation: MA has adopted the bonding requirements from NFPA 70 and NFPA 54,
requiring CSST to be bonded to the grounding electrode system using a 6 AWG or
larger copper conductor to prevent arcing from lightning strikes.
7. A gas appliance flue vent connector that passes through a combustible wall must
have a clearance of at least:
a) 1 inch
b) 3 inches
c) 6 inches
d) 9 inches
Answer: c) 6 inches
Explanation: NFPA 54 requires a 6-inch clearance for single-wall metal vent connectors
passing through combustible walls, unless a firestop or thimble listed for reduced
clearance is used.
, 8. When testing a low-pressure natural gas system (less than 14 in. w.c.), the test
pressure must be held for at least:
a) 10 minutes
b) 30 minutes
c) 1 hour
d) 4 hours
Answer: a) 10 minutes
Explanation: For low-pressure systems, NFPA 54 and MA code allow a 10-minute test
duration at a pressure of not less than 3 in. w.c. and not more than 14 in. w.c., with no
perceptible drop.
9. A gas meter installed inside a building in MA must be located:
a) In any utility room without restriction
b) Within 3 ft of a window for ventilation
c) In a well-ventilated area not less than 3 ft from any source of ignition
d) Directly above the water heater
Answer: c) In a well-ventilated area not less than 3 ft from any source of ignition
Explanation: MA gas code prohibits indoor meters within 3 ft of ignition sources (boilers,
water heaters, furnaces, electrical panels with arcing parts) to prevent explosion hazards.
10. The maximum allowable gas pressure inside a residential building in MA (after the
service regulator) is:
a) 0.5 psig
b) 2 psig
c) 5 psig
d) 10 psig
Answer: a) 0.5 psig
Explanation: Unless special permission is granted, MA limits residential interior gas
pressure to ½ psig (14 in. w.c.) for safety. Higher pressures (2 psig) are allowed only if
approved and with line regulators at each appliance.
Practice Exam Questions And Answers
Rated A+ New Update Assured
Satisfaction
1. A gas piping system in a commercial building in Massachusetts must be tested with
air or inert gas at a minimum pressure of:
a) 3 psi for 30 minutes
b) 10 psi for 60 minutes
c) 15 psi for 60 minutes
d) 100 psi for 24 hours
Answer: b) 10 psi for 60 minutes
Explanation: According to 248 CMR 5.00 and NFPA 54, the MA amendment requires a
pressure test of at least 10 psi (69 kPa) for 60 minutes with no measurable drop when
using air or an inert gas. The test must be performed before the system is covered or
concealed.
2. When sizing a natural gas line from a 2 psig service to a building, the allowable
pressure drop from the meter to the furthest appliance is typically:
a) 0.3 in. w.c.
b) 0.5 in. w.c.
c) 1.0 in. w.c.
d) 2.0 in. w.c.
Answer: c) 1.0 in. w.c.
Explanation: For systems operating at 2 psig with a line pressure regulator at each
,appliance, NFPA 54 allows a 1 psi drop on the high side, but the low-pressure side after
the regulator is limited to 1.0 in. w.c. drop for design purposes in MA.
3. A manual shutoff valve for a gas appliance installed in a residential garage in MA
must be located:
a) Inside the garage within 6 ft of the appliance
b) Outside the garage or within 6 ft of the appliance but not less than 3 ft above the
floor
c) At the meter only
d) Anywhere as long as it is accessible
Answer: b) Outside the garage or within 6 ft of the appliance but not less than 3 ft
above the floor
Explanation: MA amendments to NFPA 54 require garage appliance shutoffs to be
placed where they are not subject to physical damage and at least 3 ft above the garage
floor to avoid ignition of gasoline vapors.
4. A gas fitter in MA is required to have a license classification that allows work on
systems up to:
a) 250,000 Btu/hr without inspection
b) Any size if working under a master
c) Unlimited size only with a Master Gas Fitter license
d) 2 million Btu/hr with a Journeyman license
Answer: c) Unlimited size only with a Master Gas Fitter license
Explanation: Only a Master Gas Fitter license holder in MA may design, install, and
contract for gas piping and appliances of any size without supervision. Journeyman
must work under a Master.
5. The minimum burial depth for a plastic natural gas service line under a driveway in
MA is:
a) 12 in.
b) 18 in.
,c) 24 in.
d) 36 in.
Answer: c) 24 in.
Explanation: 248 CMR specifies 24 inches for plastic pipe under driveways and parking
areas, 18 inches under roads, and 12 inches under non-traffic areas, but the stricter
depth for driveways is 24 inches.
6. A CSST (corrugated stainless steel tubing) bonding requirement in MA mandates that
the CSST be bonded to the:
a) Neutral bus in the main panel
b) Grounding electrode system with a minimum 6 AWG copper conductor
c) Gas meter housing only
d) Water pipe within 5 ft of entry
Answer: b) Grounding electrode system with a minimum 6 AWG copper conductor
Explanation: MA has adopted the bonding requirements from NFPA 70 and NFPA 54,
requiring CSST to be bonded to the grounding electrode system using a 6 AWG or
larger copper conductor to prevent arcing from lightning strikes.
7. A gas appliance flue vent connector that passes through a combustible wall must
have a clearance of at least:
a) 1 inch
b) 3 inches
c) 6 inches
d) 9 inches
Answer: c) 6 inches
Explanation: NFPA 54 requires a 6-inch clearance for single-wall metal vent connectors
passing through combustible walls, unless a firestop or thimble listed for reduced
clearance is used.
, 8. When testing a low-pressure natural gas system (less than 14 in. w.c.), the test
pressure must be held for at least:
a) 10 minutes
b) 30 minutes
c) 1 hour
d) 4 hours
Answer: a) 10 minutes
Explanation: For low-pressure systems, NFPA 54 and MA code allow a 10-minute test
duration at a pressure of not less than 3 in. w.c. and not more than 14 in. w.c., with no
perceptible drop.
9. A gas meter installed inside a building in MA must be located:
a) In any utility room without restriction
b) Within 3 ft of a window for ventilation
c) In a well-ventilated area not less than 3 ft from any source of ignition
d) Directly above the water heater
Answer: c) In a well-ventilated area not less than 3 ft from any source of ignition
Explanation: MA gas code prohibits indoor meters within 3 ft of ignition sources (boilers,
water heaters, furnaces, electrical panels with arcing parts) to prevent explosion hazards.
10. The maximum allowable gas pressure inside a residential building in MA (after the
service regulator) is:
a) 0.5 psig
b) 2 psig
c) 5 psig
d) 10 psig
Answer: a) 0.5 psig
Explanation: Unless special permission is granted, MA limits residential interior gas
pressure to ½ psig (14 in. w.c.) for safety. Higher pressures (2 psig) are allowed only if
approved and with line regulators at each appliance.
