This free plumbing practice test will give you an idea of the types of questions that appear on actual plumbing licensing exams. Plumbing exams vary by state but most all states and local plumbing jurisdictions have adopted either the IPC or the UPC plumbing codes. Typical exam sections include: fixtures, sanitary drainage systems, administrative policies, venting, indirect and special wastes, etc.

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1.	A plumbing permit is required for the replacement of which of the following?
		a. Water closet
		b. Water heater
		c. Bathing unit
		d. Faucet

2.	The provisions for licensing are determined by which of the following:
		a. State Board of Plumbing
		b. Authority having jurisdiction
		c. Plumbing inspector
		d. The responsible master plumber

3.	Which of the following is suitable for testing a DWV system for leaks?
		a. Air
		b. Water
		c. Smoke
		d. All of the above

4.	All pipe used in plumbing applications will have all of the following markings except:
		a. Pressure rating in psi
		b. Nominal pipe size
		c. Length of pipe
		d. Manufacturer's brand name

5.	What is the likely height of a handicap toilet?
		a. 13 inches
		b. 15 inches
		c. 18 inches
		d. 22 inches

6.	What is the minimum unobstructed opening of egress when a shower door is installed for a typical shower?
		a. 22 inches
		b. 24 inches
		c. 28 inches
		d. 30 inches

7.	Which of the following is considered to be the best method for connecting an indirect waste to a sanitary drainage system?
		a. Air gap
		b. Air break
		c. Both a and b are equal
		d. None of the above

8.	The minimum vertical distance from the bottom of an indirect drain line to its receptor's flood rim is _____________________________.
		a. 1"
		b. ¾"
		c. ½"
		d. 2"

9.	Which of the following types of fixtures can be served by a combination-waste-and-vent system?
		a. Urinals
		b. Toilets
		c. Sinks
		d. Bidets

10.	You are connecting two back to back lavatories, two urinals and two water closets to one horizontal branch. What are the maximum number fixtures that can be connected to a horizontal branch?
		a. 3
		b. 4
		c. 6
		d. 8

11.	Piping for building drains and horizontal drainage branches require the installation of cleanouts. Spacing for these cleanouts is determined by the diameter of the drain and other factors. In this scenario the drain pipe diameter is three inches. This drain has a running length of 40 feet. During this run the pipe takes one 90-degree turn and on one 45-degree turn. How many cleanouts are required for this installation?
		a. 2
		b. 3
		c. 4
		d. 6

12.	One trap arm may serve a total of how many P-traps?
		a. 3
		b. 1
		c. 2
		d. 4

13.	Flexible water connections are required to be _________.
		a. Readily accessible
		b. Accessible
		c. Limited to first-floor installations
		d. Supported

14.	Water heaters, hose bibs and sill cocks are normally protected from backflow with ________.
		a. An air gap
		b. An air break
		c. A vacuum breaker
		d. A reduced-pressure backflow preventer

15.	What is the typical amount of grade required per liner foot on a household drainage pipe?
		a. 1/8 inch
		b. 1/4 inch
		c. 3/4 inch
		d. 1 inch

16.	What will result when a 4 inch pipe is reduced in size in the direction of the flow?
		a. The waste will travel faster which will allow for better cleaning of the pipe.
		b. This could cause blockage to build up at the reduction point.
		c. This could cause slugging in the waste system.
		d. This will have no affect on the drainage system.

17.	In Med Gas systems, the exhaust from vacuum pumps must be discharged into the following:
		a. Designated receptor
		b. Indirect drain
		c. Outdoors
		d. Relief vent

18.	Flux can only be used in the brazing process when:
		a. Brazing copper to brass
		b. Brazing copper to copper
		c. Not allowed
		d. Both a and b

19.	Where is the maximum allowable working pressure of a storage tank and water heater required to be shown?
		a. In the installation guide
		b. Stamped in the metal
		c. On a permanently attached plate
		d. Either b or c

20.	The minimum depth thickness for a water heater drip pan is __________________________.
		a. 1"
		b. 1.5"
		c. 3/4"
		d. 2"

21.	Gray water that enters a collection reservoir must be ________.
		a. Measured
		b. Flow controlled
		c. Filtered
		d. Monitored

22.	What is the maximum amount of time that gray water is allowed to be retained for use to flush a toilet or urinal?
		a. 24 hours
		b. 48 hours
		c. 72 hours
		d. 96 hours

23.	Gas piping installed in a laundry chute ____________.
		a. Must be secured at maximum intervals of 6 feet
		b. Must be protected from damage in the normal course of use of the chute
		c. Is required to be installed with only vertical pipe sections
		d. Is a code violation

24.	When flow controls are installed on gas piping, they _____________.
		a. Must be accessible
		b. Must not contain sediment traps
		c. Must be equipped with a leak-limiting device
		d. Are used to keep operating pressure lower than the supply pressure

25.	What is the angle made when you offset a sewer with a 1/8 bend?
		a. 45°
		b. 60°
		c. 72°
		d. 90°

26.	What is the total pressure in pound per square inch (psi) on a 6 inch diameter test plug with a water head of 15 feet?
		a. 3.00 psi
		b. 4.25 psi
		c. 6.51 psi
		d. 7.20 psi

Administrative Policies and Procedures

1.	A plumbing permit is required for the replacement of which of the following?
		a. Water closet
		b. Water heater
		c. Bathing unit
		d. Faucet
A plumbing permit is not needed for the direct replacement of any plumbing fixture, except for a water heater. However, if a fixture location is changed, a permit is required. In other words, you can remove a toilet and replace it with a new one without the need for a permit. But, if you move the closest flange in any way, a permit is required. This is true for all plumbing fixtures. Incorrect answer. Please choose another answer.

General Regulations

3.	Which of the following is suitable for testing a DWV system for leaks?
		a. Air
		b. Water
		c. Smoke
		d. All of the above
It is common for modern DWV systems to be tested with air. In the old days water was the most common means of testing. When there is a leak that cannot be found easily, smoke can be used to expose the leak location. Smoke is not used as a primary test method. Air is the test medium of choice. The testing of a DWV system is to be conducted for a minimum of 15 minutes. The minimum test pressure is required to be 10 pounds per square inch (PSI). If only underground plumbing is being tested there must be one riser that is at least ten feet above the main plumbing system. Incorrect answer. Please choose another answer.

Fixtures

5.	What is the likely height of a handicap toilet?
		a. 13 inches
		b. 15 inches
		c. 18 inches
		d. 22 inches
Handicap toilets are available with heights that include 16 inches, 18 inches and 20 inches. Eighteen inches is the most common height of a standard handicap toilet. Incorrect answer. Please choose another answer.

Indirect and Special Wastes

7.	Which of the following is considered to be the best method for connecting an indirect waste to a sanitary drainage system?
		a. Air gap
		b. Air break
		c. Both a and b are equal
		d. None of the above
An air gap is believed to be superior to an air break for the protection of an indirect wastepipe from back siphonage. Due to the nature of installation there is more risk of a backflow occurring with an air break. Since air breaks have discharge piping entering a receptor it is feasible to have the sanitary drain become clogged and back up, which could result in contaminated waste traveling back to the indirect waste fixture. This is not possible when an air gap is used. Incorrect answer. Please choose another answer.

Vents and Venting

9.	Which of the following types of fixtures can be served by a combination-waste-and-vent system?
		a. Urinals
		b. Toilets
		c. Sinks
		d. Bidets
Combination-waste-and vent (CWV) systems do not require independent vents on all fixtures. Instead of a vertical vent the fixtures approved for a CWV installation are installed with oversized drains. Due to the larger drain diameter the fixture obtains the needed air for drainage in the top section of the oversized piping. Urinals, toilets and bidets are not allowed to be installed on CWV systems. Incorrect answer. Please choose another answer.

Traps and Cleanouts

12.	One trap arm may serve a total of how many P-traps?
		a. 3
		b. 1
		c. 2
		d. 4
Not more than one trap is permitted on a trap arm. Incorrect answer. Please choose another answer.

Water Supply and Distribution

14.	Water heaters, hose bibs and sill cocks are normally protected from backflow with ________.
		a. An air gap
		b. An air break
		c. A vacuum breaker
		d. A reduced-pressure backflow preventer
Vacuum breakers are normally used to protect water heaters, sill cocks and hose bibs from backflow dangers. Incorrect answer. Please choose another answer.

Sanitary Drainage Systems

15.	What is the typical amount of grade required per liner foot on a household drainage pipe?
		a. 1/8 inch
		b. 1/4 inch
		c. 3/4 inch
		d. 1 inch
The amount of grade, also referred to as pitch or fall, for a drain pipe is determined by the size of the drain pipe. Master plumbers and other design professional establish these elements of a plumbing system based on the minimum standards required by local code requirements. As a general rule-of thumb, the proper amount of grade for a drain up to 4-inches in diameter is .25 inch per liner foot. Incorrect answer. Please choose another answer.

Special Piping and Storage Systems

17.	In Med Gas systems, the exhaust from vacuum pumps must be discharged into the following:
		a. Designated receptor
		b. Indirect drain
		c. Outdoors
		d. Relief vent
Exhaust must be discharged outdoors in a way which will minimize the hazard of noise and contamination to the environment. Incorrect answer. Please choose another answer.

Water Heaters

19.	Where is the maximum allowable working pressure of a storage tank and water heater required to be shown?
		a. In the installation guide
		b. Stamped in the metal
		c. On a permanently attached plate
		d. Either b or c
Such markings shall be in an accessible position outside of the tank, permanently affixed. Incorrect answer. Please choose another answer.

Recycling Gray Water

21.	Gray water that enters a collection reservoir must be ________.
		a. Measured
		b. Flow controlled
		c. Filtered
		d. Monitored
Any gray water going into a gray-water collection reservoir is required to be filtered. This is required as a means of blocking solids from entering the collection reservoir. While the fixtures allowed for the recycling of gray water should not be transporting solids there is always a possibility the some type of solid could find its way into the drainage water. The filters stop these impurities from reaching the collection of gray water that will be recycled. Incorrect answer. Please choose another answer.

Fuel Gas

23.	Gas piping installed in a laundry chute ____________.
		a. Must be secured at maximum intervals of 6 feet
		b. Must be protected from damage in the normal course of use of the chute
		c. Is required to be installed with only vertical pipe sections
		d. Is a code violation
Gas piping in not allowed to be installed in laundry chutes, dumbwaiters, air-circulating ducts or elevators. The chutes, shafts and ducts can transport gas to various locations in a building if a leak should occur. Therefore, it is inappropriate to install gas piping in a location that could distribute gas beyond the location of the leak. Incorrect answer. Please choose another answer.

Math

25.	What is the angle made when you offset a sewer with a 1/8 bend?
		a. 45°
		b. 60°
		c. 72°
		d. 90°
Degree of Angle = Fitting x 360 Degrees Degree of Angle = 0.125 x 360 Degrees Degree of Angle = 45 degrees Incorrect answer. Please choose another answer.

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