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 NM-JP exam has 70 questions and runs 3 hours 5 minutes.
These 10 free NM-JP questions are organized by exam domain, so you can see how each part of the New Mexico Journeyman Plumber (JP) Certificate of Competence Exam blueprint is tested. Reveal the answer and explanation under each question.
A remodel adds a basement bathroom on a floor at elevation 94.0 ft. The existing first-floor fixtures are on a floor at 106.0 ft, and the cover of the next upstream public-sewer manhole is at 100.0 ft. Both floors can drain to the sewer by gravity. How should sewage-backup protection be arranged?
Correct answer: D - Protect only the basement branch with an accessible backwater valve.
A new 3-inch horizontal sanitary drain must run 28 feet from an upstream invert of 100.00 ft to a proposed downstream invert of 99.50 ft. No engineered alternative has been approved, and the upstream elevation must stay fixed. Which proposal meets the minimum-grade requirement throughout the run?
Correct answer: D - Lower the downstream invert to 99.30 ft and maintain a uniform fall.
Since a water meter with an integral check valve was installed, a home's pressure rises from 62 psi to 116 psi during water-heater recovery when no fixtures are running. Pressure upstream of the meter stays near 62 psi. Opening a faucet promptly brings the house pressure back down. What best explains this pattern?
Correct answer: C - Thermal expansion is pressurizing the closed water system.
A potable-water makeup connection serves a chemical process containing a toxic additive. A downstream pump can raise process pressure above the supply pressure, and the connection must remain continuously pressurized. The design calls for a mechanical backflow assembly rather than an air-gapped break tank. Which assembly fits these conditions?
Correct answer: A - Reduced-pressure-principle assembly
A fixed potable-water outlet with a 3/4-inch effective opening fills an open tank. The outlet is unobstructed, nearby walls do not affect the air gap, and its lowest point is 1-3/4 inches above the tank's flood-level rim. The operating water level is lower still. Does this arrangement meet the supply air-gap requirement?
Correct answer: A - Yes; the present separation above the flood-level rim is adequate.
For a parapet-enclosed roof, the design-storm runoff is 160 gpm. The primary drainage system is sized for that flow. A separate, independent secondary system is proposed at 64 gpm on the assumption that the primary system will still carry the balance during an emergency. What is wrong with the proposal?
Correct answer: C - It must carry the entire 160-gpm demand with the primary blocked.
A residential washer-box rough-in will use a 2-inch trap and drain with a compliant vent. Standpipe height is measured from the trap weir to the open top. Which pair of elevations meets the 2021 UPC requirements?
Correct answer: D - Trap weir 10 inches above the floor; standpipe 24 inches above the weir.
After rain, the competent person finds fresh tension cracks along a 4-1/2-foot-deep sewer trench where employees are laying pipe. The excavation is in soil, not stable rock, and has no cave-in protective system. The foreman argues that protection starts at 5 feet. What should happen now?
Correct answer: B - Remove the workers until adequate cave-in protection is provided.
A restaurant reports grease carryover from a hydromechanical interceptor rated for 50 gpm and 100 lb of grease retention. Recorded peak inflow is 32 gpm, the flow-control device is functioning, and the internal baffles are intact. The last cleaning recovered 120 lb of accumulated grease. Which change is most likely to prevent recurrence?
Correct answer: C - Shorten the cleaning interval to stay within the grease-retention capacity.
An isometric shows two parallel copper runs with their centerlines 24 inches apart in the same plane. The offset is made with two 45-degree elbows. Each elbow requires a 2-inch deduction from the center-to-center travel; these deductions already account for socket engagement. To the nearest 1/16 inch, how long should the straight tube between the elbows be cut?
Correct answer: B - 29 15/16 inches
The NM-JP exam also covers these domains. Drill them in the full free practice test:
The full bank has 1,020 more NM-JP questions with explanations.
Continue in the free practice test →
View plans