10 exam-style questions with answers and explanations, straight from our 1,030-question bank. Tap an answer to check yourself. When you're ready, take the scored version in the free practice test.
The MD-JP exam has 100 questions and runs 4 hours.
These 10 free MD-JP questions are organized by exam domain, so you can see how each part of the Maryland Journeyman Plumber License Exam blueprint is tested. Reveal the answer and explanation under each question.
Domain 1: PLUMBING FUNDAMENTALS AND SAFETY
Question 1
For an 8-foot-deep sewer trench, a competent person's visual and manual tests identify dry cohesive soil with an unconfined compressive strength of 1.8 tons per square foot. Site records identify it as backfill from an earlier utility excavation. There are no sloping soil layers, surcharge loads, or signs of distress. Under OSHA's ordinary simple-slope provisions, which classification and maximum slope apply? Ratios are horizontal to vertical.
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Correct answer: C - Type B; 1:1
Domain 2: MATERIALS, USES, AND SPECIFICATIONS
Question 2
A drawing revision calls for a thicker-walled replacement section in a 2-inch Type L copper hot-water line. The nominal size and existing solder fittings are to remain unchanged. Which copper-tube marking belongs on the purchase order?
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Correct answer: B - Green-marked Type K
Domain 4: PLUMBING FIXTURES, FIXTURE FITTINGS, AND PLUMBING APPLIANCES
Question 3
A conventional two-handle shower becomes sharply hotter whenever a nearby toilet refills. A central ASSE 1017 mixing valve already controls the hot-water distribution temperature. The shower is being replaced under the 2018 IPC. Which control provides the required protection at the shower?
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Correct answer: D - An ASSE 1016 automatic compensating shower valve field-limited to 120°F
Domain 5: WATER SUPPLY SYSTEMS
Question 4
Since a check valve was installed at a home's water service, pressure rises from 62 psi to 104 psi during water-heater recovery with every fixture closed. Opening a faucet promptly returns the pressure to 62 psi. There is no banging when fixtures shut off. Which correction addresses the cause of this pattern?
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Correct answer: B - Install a properly sized expansion tank between the check valve and the water heater.
Domain 6: BACKFLOW PREVENTION
Question 5
A chemical-processing unit needs a continuously pressurized, directly piped potable-water makeup connection. Its process fluid is toxic, and a process pump can raise downstream pressure to 95 psi while the potable supply is at 60 psi. Which assembly provides the required protection against this combination of hazard and reverse-flow mechanism?
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Correct answer: C - A reduced-pressure principle backflow-prevention assembly
Question 6
An annual test of a correctly installed pressure vacuum breaker on a lawn-irrigation supply produces these results: the check holds a 2.2-psi differential, and the air inlet opens at 1.4 psi above atmospheric pressure. Test conditions are valid and the shutoffs hold. The irrigation system has downstream zone valves, but no chemical injection or backpressure source. Using the EPA Cross-Connection Control Manual's field-test criteria, how should the assembly be assessed?
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Correct answer: B - Pass; both readings meet the applicable component acceptance criteria.
Domain 7: DRAIN, WASTE, AND VENT SYSTEMS
Question 7
Moving a lavatory leaves its 1 1/2-inch trap arm with 7 feet of developed length to the vent takeoff. The arm has a uniform slope of 1/4 inch per foot, and the trap and vent are otherwise correctly installed. The plumber must retain the 1 1/2-inch trap arm. Under the ordinary 2018 IPC trap-to-vent provisions, the needed change is to:
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Correct answer: D - Relocate the vent takeoff within the permitted trap-arm length.
Domain 8: GAS APPLIANCES AND PIPING
Question 8
A 20-foot common gas trunk supplies a furnace rated at 100,000 Btu/h input and 80,000 Btu/h output, a 45,000-Btu/h-input water heater, and a 30,000-Btu/h-input dryer. All three may operate together. The longest developed route from the point of delivery to an appliance is 73 feet. Natural gas has a heating value of 1,000 Btu/ft³.
Use the 2018 IFGC longest-length method and these Schedule 40 capacities in cubic feet per hour. Conditions: inlet pressure below 2 psi, 0.3-inch-water-column pressure drop, and gas specific gravity 0.60.
Nominal size: 3/4 inch | 1 inch | 1 1/4 inches | 1 1/2 inches
20-foot row: 188 | 353 | 726 | 1,090
80-foot row: 89 | 167 | 343 | 514
What is the smallest listed size for the common trunk?
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Correct answer: C - 1 1/4 inches
Question 9
On arrival for a gas-water-heater service call, a plumber hears a carbon-monoxide alarm. Two occupants report headache and dizziness, but neither notices a fuel-gas odor. What takes priority over examining the appliance?
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Correct answer: A - Get everyone outside and call emergency services from a safe location.
Question 10
A replacement furnace operates with positive static pressure in its vent, and its flue gases produce condensate during normal operation. The previous furnace used Type B gas vent. Which classification and venting approach fit the replacement appliance?
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Correct answer: A - Category IV; use a listed pressure-tight vent system suitable for condensate.