Free Practice Questions for MD Plumber

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Exam Review

Key Facts: MD Plumber Exam

70%

Passing Score

Maryland Board of Plumbing

100

Exam Questions

PSI bulletin

240 min

Time Limit

PSI bulletin

IPC

Code Base

Maryland adoption

Maryland's Journey Plumber/Gas Fitter exam, given by PSI for the State Board of Plumbing, has 100 questions, 240 minutes and a 70% passing score. It is open book: the 2018 IPC and 2018 IFGC are allowed references. The exam fee is $65.

Sample MD Plumber Practice Questions

Try these sample questions to review concepts for the MD Plumber exam. Each question includes a detailed explanation. Start the interactive quiz above for the full 355+ question experience with AI tutoring.

1Per the IPC as adopted by Maryland, what is the minimum slope for a 4-inch horizontal drain pipe?

A.1/16 inch per foot

B.1/8 inch per foot

C.1/4 inch per foot

D.1/2 inch per foot

Explanation: Under 2018 IPC Table 704.1, 3-inch through 6-inch horizontal drainage piping requires a minimum slope of 1/8 inch per foot. A 4-inch drain falls in that range.

2A propane leak develops in a basement mechanical room. Where will the propane tend to collect?

A.Near the floor and in low spots because propane vapor is heavier than air

B.Near the ceiling because propane vapor is lighter than air

C.Evenly at all elevations because propane has the same density as air

D.Only next to the appliance because propane does not migrate

Explanation: Propane vapor has a specific gravity greater than 1 relative to air, so an escaping cloud tends to settle and accumulate near the floor and in low areas.

3A natural-gas water heater is rated at 125,000 Btu/h. Using a nominal heating value of 1,000 Btu per cubic foot, what gas flow must the piping supply?

A.50 cubic feet per hour

B.125 cubic feet per hour

C.250 cubic feet per hour

D.500 cubic feet per hour

Explanation: Divide the appliance input by the gas heating value: 125,000 Btu/h ÷ 1,000 Btu/ft³ = 125 cubic feet per hour.

4Per the IPC, cleanouts in horizontal drains must be installed at intervals not exceeding what distance?

A.50 feet

B.75 feet

C.100 feet

D.125 feet

Explanation: Per the International Plumbing Code (IPC), cleanouts must be installed at maximum 100-foot intervals in horizontal drainage lines. They are also required at changes of direction and at the upper terminal of the building drain.

5Under 2018 IPC Table 709.1, what is the minimum fixture-drain size for a floor-outlet water closet?

A.1-1/2 inches

B.2 inches

C.3 inches

D.4 inches

Explanation: Under 2018 IPC Table 709.1, a floor-outlet water closet requires a fixture drain at least 3 inches in diameter.

6Under the 2018 IFGC, copper tubing may not convey fuel gas containing more than what average hydrogen-sulfide concentration?

A.0.3 grain per 100 standard cubic feet

B.0.3 grain per standard cubic foot

C.3 grains per 100 standard cubic feet

D.30 grains per 100 standard cubic feet

Explanation: IFGC Section 403.5.2 prohibits copper and copper-alloy tubing where the gas contains more than an average of 0.3 grain of hydrogen sulfide per 100 standard cubic feet.

7Under the 2018 IFGC, where may polyethylene fuel-gas piping be installed?

A.Outdoors underground, with above-grade transition through an approved riser

B.Concealed inside building walls

C.Exposed inside a mechanical room

D.Under a building slab without conduit or venting

Explanation: IFGC Section 404.17 limits plastic fuel-gas piping to outdoor underground installation. The transition above grade is made through an approved riser.

8Per the IPC, what fitting is required for a horizontal-to-horizontal direction change in drainage piping?

A.Short-sweep quarter bend

B.Long-sweep quarter bend or equivalent

C.Standard tee fitting

D.Any available fitting

Explanation: Per the International Plumbing Code (IPC), horizontal-to-horizontal changes of direction must use long-sweep fittings. Short-sweep fittings are restricted to horizontal-to-vertical transitions.

9Per the IPC, indirect waste from a commercial dishwasher must discharge through what?

A.A direct connection to the building drain

B.An air gap to an approved receptor

C.A check valve

D.A backwater valve

Explanation: Per the International Plumbing Code (IPC), indirect waste from commercial food equipment must discharge through an air gap into an approved floor sink or receptor to prevent contamination.

10Using the longest-length method, the most remote gas outlet is 88 feet from the meter after fitting allowances. Which table row is used to size every section?

A.The 90-foot row for every section of the system

B.The 30-foot row for each short branch

C.The 80-foot row because it is closest

D.The 100-foot row because all lengths are rounded to 100 feet

Explanation: The longest-length method uses the longest run for every section and rounds upward to the next listed table length. An 88-foot run therefore uses the 90-foot row.

About the MD Plumber Exam

Maryland's Journey Plumber/Gas Fitter exam is a 100-question, open-book PSI exam with 240 minutes and a 70% passing score. Gas appliances and piping make up 40 questions; the rest cover plumbing fundamentals, materials, traps, fixtures, water supply, backflow, drain, waste and vent systems, and plumbing math.

Exam sponsor: Maryland Board of Plumbing. The requirements and fees below concern the certification or admission exam, separate from our free practice resources.

Questions

100 questions

Time Limit

240 minutes

Passing Score

70%

Exam / Certification Fees

$65

Exam sponsor website

Reported exam pass rate: ~55-65%. This describes exam candidates, not OpenExamPrep users or results from using our resources. Exam sponsor website

Fees, eligibility, and exam policies can change. Confirm them with the exam sponsor before applying or paying.

Official sources

Our practice resources: topics covered

We aim to reflect publicly available exam outlines and topic information in our study resources. Coverage, format, and difficulty may differ from the actual exam, and we cannot guarantee that every detail is accurate or current. Confirm exam requirements, fees, and policies with the official exam sponsor.

8 questions

Plumbing Fundamentals and Safety

Plumbing terms, general regulations and jobsite safety (29 CFR 1926 is an allowed reference)

6 questions

Materials, Uses, and Specifications

Pipe, fitting and joint materials and their approved uses

4 questions

Traps, Interceptors, and Backwater Valves

Trap seals, interceptors and separators, backwater valves

4 questions

Plumbing Fixtures, Fixture Fittings, and Plumbing Appliances

Fixture requirements, fittings and water heaters

8 questions

Water Supply Systems

Water distribution, sizing and protection of potable water

10 questions

Backflow Prevention

Cross-connections, air gaps and backflow devices

13 questions

Drain, Waste, and Vent Systems

Drainage fixture units, pipe sizing, slope and venting

40 questions

Gas Appliances and Piping

Fuel gas piping, sizing, appliances, venting and purging under the 2018 IFGC

7 questions

Plumbing Mathematics

Plumbing and pipefitting calculations

Preparing for the MD Plumber Exam

What You Need to Know

Passing score: 70%
Exam length: 100 questions
Time limit: 240 minutes
Exam / certification fees: $65 Official sources

Using Our Practice Resources

Work through all 355 available questions
Review every answer and explanation
Track weak areas and revisit them
Use our AI tutor for tough concepts

MD Plumber: Suggested Study Strategy

1Study the IPC thoroughly — learn to navigate the index and tables quickly for the open-book PSI exam

2Master DFU calculations and drain pipe sizing using IPC fixture unit tables

3Practice vent sizing and understand when wet venting, circuit venting, and air admittance valves are permitted

4Memorize minimum pipe sizes for common fixtures and trap arm distances

5Review backflow prevention device selection based on hazard level

6Study water heater installation requirements including T&P relief valve discharge

7Practice gas pipe sizing calculations using BTU input ratings and pipe length tables

8Review Maryland-specific plumbing regulations and any state amendments to the IPC

Frequently Asked Questions

How hard is the Maryland journeyman plumber exam?

It has 100 questions in 240 minutes and needs 70% to pass. Gas appliances and piping is the largest area (40 questions), followed by drain, waste and vent systems (13) and backflow prevention (10).

What plumbing code does Maryland use?

PSI's bulletin (updated 9/1/2024) allows the 2018 International Plumbing Code and 2018 International Fuel Gas Code in the open-book exam. By regulation (COMAR 09.20.01.01), the Board adopts the most recent IPC and IFGC, with Maryland modifications.

How much does the Maryland plumber exam cost?

The Journey Plumber/Gas Fitter exam fee is $65, paid to PSI. Registration fees are not refundable or transferable.

What are the experience requirements for Maryland journeyman plumber?

Applicants with Maryland experience need four years as a licensed apprentice plumber, totaling at least 7,500 hours under a licensed Maryland master plumber. Every applicant also needs an approved 32-hour backflow prevention device testing course.

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