Massachusetts Plumbing Code {248 CMR} 2026-
2027 Comprehensive Frequently Tested Exam
Questions With Verified Multiple Choice and
Conceptual Actual 100% Correct Detailed Answers
Guaranteed Pass!!Current Update!!
1. What must be done to prevent contamination in a potable water supply
system? - ANSWER The system must be designed and maintained to
prevent contamination from non-potable liquids, solids, or gases.
2. What is the requirement for labeling potable and non-potable piping
systems? - ANSWER They must be labeled at least every ten feet, at all
changes of direction, and at every shut-off valve.
3. What is the role of the Massachusetts Department of Environmental
Protection (DEP) regarding cross connections? - ANSWER The DEP is
responsible for preventing contamination of drinking water and must
approve installations requiring backflow preventers.
4. What is the maximum number of tanks that can be installed in tandem
without ASME compliance? - ANSWER A maximum of four tanks may be
installed in tandem.
,5. What is the requirement for a T&P relief valve discharge outlet? - ANSWER
The discharge outlet must be full-size and piped using non-ferrous
material rated to withstand the maximum relief valve temperature.
6. What is the requirement for a mixing valve in a combination potable
water/space heating system? - ANSWER A mixing valve must be
installed for service to the plumbing fixtures.
7. What is the significance of UL-174 testing for water tanks? - ANSWER
Tanks must conform to specific pressure testing standards to ensure safety
and compliance.
8. What is the requirement for the ASME data sheet for water heaters? -
ANSWER A copy of the ASME data sheet must be provided to the owner
and displayed near the water heater.
9. What is the minimum warranty period for tanks to be exempt from ASME
compliance? - ANSWER The tank must have a minimum warranty of ten
years.
10.What is the requirement for the sizing of vacuum relief valves? - ANSWER
Vacuum relief valves must be a minimum of one pipe size smaller than
the tank drain size.
11.What type of valves are required for tankless heaters connected to low
pressure steam and hot water heating boilers? - ANSWER The pressure
relief valve must be sized according to specific CMR regulations.
,12.What is the requirement for the number of valves needed for tank drain
sizes? - ANSWER The number of valves required is specified in a sizing
chart based on the size of the tank drain.
13.What must be done if a plumbing permit is required for cross connection
installations? - ANSWER The permit application must include a letter of
approval from the Massachusetts DEP.
14.What is the primary regulation governing drinking water quality in the U.S.?
- ANSWER The Safe Drinking Water Act (SWDA), 42 U.S.C. § 300f et. seq.
15.What is required for buildings used for human occupancy regarding water
supply? - ANSWER Every building must be provided with an adequate
supply of potable water and hot water.
16.What types of water are prohibited for use in plumbing fixtures for drinking,
bathing, and food processing? - ANSWER Only potable water is allowed;
non-potable water is prohibited.
17.What factors determine the sizing of building water piping? - ANSWER
Sizing is based on total demand and procedures outlined in 248 CMR 10.14.
18.What is the minimum size of a fixture supply pipe determined by? -
ANSWER It is determined using 248 CMR 10.14(4): Table 1.
, 19.What must be included in the design of water supply systems with quick-
acting valves? - ANSWER Devices to absorb high pressures must be
included to prevent water hammer.
20.What is the purpose of pressure-absorbing devices in water supply
systems? - ANSWER They absorb high pressures resulting from the quick
closing of valves.
21.What is the minimum flow pressure required at fixture outlets according to
248 CMR? - ANSWER The minimum flow pressure is specified in 248
CMR 10.14(4): Table 4.
22.What should be installed if water pressure is insufficient to meet fixture
outlet requirements? - ANSWER A booster pump and pressure tank or
other compliant means must be installed.
23.What is the flow pressure requirement for a lavatory faucet in residential
use? - ANSWER The flow pressure required is 8 PSI.
24.What should be done if the pressure exceeds 80 PSIG at any plumbing
fixture? - ANSWER A pressure reducing valve must be installed to limit
the pressure to 80 PSIG.
25.What is the maximum distance for hot water piping before a return
circulation system is required? - ANSWER A return circulation system is
required if the developed length exceeds 75 feet.
2027 Comprehensive Frequently Tested Exam
Questions With Verified Multiple Choice and
Conceptual Actual 100% Correct Detailed Answers
Guaranteed Pass!!Current Update!!
1. What must be done to prevent contamination in a potable water supply
system? - ANSWER The system must be designed and maintained to
prevent contamination from non-potable liquids, solids, or gases.
2. What is the requirement for labeling potable and non-potable piping
systems? - ANSWER They must be labeled at least every ten feet, at all
changes of direction, and at every shut-off valve.
3. What is the role of the Massachusetts Department of Environmental
Protection (DEP) regarding cross connections? - ANSWER The DEP is
responsible for preventing contamination of drinking water and must
approve installations requiring backflow preventers.
4. What is the maximum number of tanks that can be installed in tandem
without ASME compliance? - ANSWER A maximum of four tanks may be
installed in tandem.
,5. What is the requirement for a T&P relief valve discharge outlet? - ANSWER
The discharge outlet must be full-size and piped using non-ferrous
material rated to withstand the maximum relief valve temperature.
6. What is the requirement for a mixing valve in a combination potable
water/space heating system? - ANSWER A mixing valve must be
installed for service to the plumbing fixtures.
7. What is the significance of UL-174 testing for water tanks? - ANSWER
Tanks must conform to specific pressure testing standards to ensure safety
and compliance.
8. What is the requirement for the ASME data sheet for water heaters? -
ANSWER A copy of the ASME data sheet must be provided to the owner
and displayed near the water heater.
9. What is the minimum warranty period for tanks to be exempt from ASME
compliance? - ANSWER The tank must have a minimum warranty of ten
years.
10.What is the requirement for the sizing of vacuum relief valves? - ANSWER
Vacuum relief valves must be a minimum of one pipe size smaller than
the tank drain size.
11.What type of valves are required for tankless heaters connected to low
pressure steam and hot water heating boilers? - ANSWER The pressure
relief valve must be sized according to specific CMR regulations.
,12.What is the requirement for the number of valves needed for tank drain
sizes? - ANSWER The number of valves required is specified in a sizing
chart based on the size of the tank drain.
13.What must be done if a plumbing permit is required for cross connection
installations? - ANSWER The permit application must include a letter of
approval from the Massachusetts DEP.
14.What is the primary regulation governing drinking water quality in the U.S.?
- ANSWER The Safe Drinking Water Act (SWDA), 42 U.S.C. § 300f et. seq.
15.What is required for buildings used for human occupancy regarding water
supply? - ANSWER Every building must be provided with an adequate
supply of potable water and hot water.
16.What types of water are prohibited for use in plumbing fixtures for drinking,
bathing, and food processing? - ANSWER Only potable water is allowed;
non-potable water is prohibited.
17.What factors determine the sizing of building water piping? - ANSWER
Sizing is based on total demand and procedures outlined in 248 CMR 10.14.
18.What is the minimum size of a fixture supply pipe determined by? -
ANSWER It is determined using 248 CMR 10.14(4): Table 1.
, 19.What must be included in the design of water supply systems with quick-
acting valves? - ANSWER Devices to absorb high pressures must be
included to prevent water hammer.
20.What is the purpose of pressure-absorbing devices in water supply
systems? - ANSWER They absorb high pressures resulting from the quick
closing of valves.
21.What is the minimum flow pressure required at fixture outlets according to
248 CMR? - ANSWER The minimum flow pressure is specified in 248
CMR 10.14(4): Table 4.
22.What should be installed if water pressure is insufficient to meet fixture
outlet requirements? - ANSWER A booster pump and pressure tank or
other compliant means must be installed.
23.What is the flow pressure requirement for a lavatory faucet in residential
use? - ANSWER The flow pressure required is 8 PSI.
24.What should be done if the pressure exceeds 80 PSIG at any plumbing
fixture? - ANSWER A pressure reducing valve must be installed to limit
the pressure to 80 PSIG.
25.What is the maximum distance for hot water piping before a return
circulation system is required? - ANSWER A return circulation system is
required if the developed length exceeds 75 feet.
