Self-Test D-4.2 Testing Methods

Complete Self-Test D-4.2 and check your answers.

1. Which of the following test methods for DWV piping is potentially more dangerous to the personnel conducting the test in the event of component failure?
   1. Air test
   2. Water test
   3. Smoke test
   4. Ball test

    

2. When conducting a 35 kPa (5 psig) air test on a DWV system, what is the maximum setpoint of the pressure regulator used to control test pressure?
   1. 35 kPa (5 psig)
   2. 49 kPa (7 psig)
   3. 63 kPa (9 psig)
   4. 77 kPa (11 psig)

    

3. What is the main advantage of using test plugs as opposed to glue- or solder-in-place test caps?
   1. The test plugs are less expensive.
   2. The test plugs can be used repeatedly.
   3. A single test plug will fit any size pipe.
   4. Test plugs will never leak once in place.

    

4. What is the most important test component that must be employed when conducting a DWV air test using compressed gas?
   1. Reliable hand pump as a backup
   2. Properly calibrated regulator
   3. High-pressure-rated test plugs
   4. Inert gas

    

5. Which testing component is typically employed when conducting a water test on a section of DWV piping where there is not an opening provided on the top of the system to introduce the water?
   1. Saddle fitting
   2. Test hub
   3. Open centre test plug
   4. Test spigot

    

6. When the AHJ requires a smoke test to be performed, how is the smoke introduced into the DWV system?
   1. Blower
   2. Compressed smoke cylinder
   3. Gravity
   4. Smoke bomb placed in the main sewer cleanout

    

7. In which of the two available styles of smoke test blowers is it easier to adjust the output in order to meet job conditions?
   1. Squirrel cage
   2. Direct-drive propeller

    

8. Where is a smoke candle placed in relation to the test blower when introducing the smoke into the system under test?
   1. At the blower exhaust
   2. At the blower intake
   3. Inside the blower housing
   4. In the piping cleanout

    

9. Which of the two types of smoke supplies used in DWV testing is more effective in producing a visible indicator of a system leak?
   1. Smoke candle
   2. Smoke fluid

    

10. Why do cast-iron soil pipe systems sometimes experience a drop in pressure when under an air test but do not show leakage when under a water test?
    1. MJ clamps are not meant to hold against static pressure above 1 in. wc.
    2. Water molecules bind together and seal pipe perforations.
    3. Air molecules are smaller than water molecules and sometimes escape through pipe perforations.
    4. Air molecules are lighter than water molecules and sometimes escape through the top of the system.

     

11. What is the maximum drop in air pressure expected by manufacturers of cast-iron soil pipe before they consider the piping system faulty?
    1. 7 kPa (1 psig)
    2. 14 kPa (2 psig)
    3. 21 kPa (3 psig)
    4. 28 kPa (4 psig)

     

12. What is the maximum preferred gauge scale for use when air testing a DWV system?
    1. Equal to test pressure
    2. Twice the test pressure
    3. Triple the test pressure
    4. Quadruple the test pressure

     

13. When performing a smoke test on a DWV system, what must the system traps be?
    1. Not installed
    2. Installed and inlets plugged
    3. Installed and filled with water
    4. Installed and inlets vented to atmosphere to verify the presence of test smoke

     

14. What does a ball test verify?
    1. Pipe alignment
    2. Pipe grade
    3. That no concentric reducing fittings are used downstream
    4. That no eccentric reducing fittings are used downstream

     

15. Which certificate does the local building department issue to indicate that a building is safe to inhabit?
    1. Plumbing final inspection report
    2. Electrical final inspection report
    3. All trade disciplines’ final inspection reports
    4. Certificate of occupancy

     

Answer Key: Self-Test D-4.2 is on the next page.