test and inspections

Overview of Tests and Inspections of Plumbing Systems

This segment covers the various methods used for testing and inspecting plumbing systems, specifically focusing on sewer systems, Drain Waste and Vent (DWV) piping systems, and water supply systems. At the end of this lesson, the procedures, parameters, and tools required for effective inspection and testing will be summarized.

Sewer Systems Testing

The sewer systems in plumbing require rigorous testing to ensure their integrity and functionality. Here are the steps to test a building sewer system:

  1. Initial Setup: Insert a test plug at the connection point with the public sewer to seal the system temporarily.

  2. Filling the System: The next step involves filling the sewer system with water. It is critical to maintain at least 10 feet of head pressure. This hydrodynamic pressure simulates the conditions under which the sewer is expected to operate.

  3. Duration of Test: Maintain this pressure for a minimum of fifteen minutes. This duration allows for the detection of any potential leaks in the system under normal operating conditions.

Drain Waste and Vent (DWV) Piping Systems Testing

DWV systems must undergo testing and inspection immediately upon the completion of their rough-in installation. The following methods can be utilized:

Water Test

  • Procedure: Fill each section of the DWV system with water until it reaches the highest point within the section.

  • Inspection Duration: Hold the water in each section for at least fifteen minutes.

  • Visual Inspection: Conduct a thorough visual inspection during this time to check for leaks.

Air Test

  • Pressurization: For the air test, the system needs to be pressurized to a gauge pressure of 5 pounds per square inch (psi) or 10 inches of mercury (Hg).

  • Duration of Pressure Maintenance: Maintain this pressure for fifteen minutes. This test verifies the integrity of joints and seals in the system without the use of water.

Testing Plumbing Fixtures

Once the plumbing fixtures have been installed, testing must be completed to ensure both water tightness and gas tightness:

  1. Water Tightness: Fill the traps of each installed fixture with water. Perform the following actions:

    • Drain each fixture and its trap and conduct a visual inspection to confirm that water tightness is maintained.

  2. Gas Tightness: This can be tested using two approaches:

    • Theatrical Smoke Generator: Introduce smoke into the DWV system; leaks will manifest where smoke escapes.

    • Peppermint Oil Method: Peppermint oil can be introduced, producing an odor if leaks are present, indicating the system is not gas tight.

Water Supply System Testing

Once the water supply system is completed, it must be tested for integrity:

  1. Water Pressure Test: The system should be tested and shown to be tight under a water pressure no less than the system's working pressure.

  2. Air Pressure Test: If conducting an air pressure test, it must not be less than 50 psi.

  3. Pressure Maintenance Duration: This pressure also needs to be maintained for at least fifteen minutes.

Test Gauge Specifications

It’s crucial when using test gauges to ensure their accuracy as follows:

  • For pressures of 10 psi or less: Utilize a gauge with increments of 0.1 psi or less.

  • For pressures between 10 psi and 100 psi: Use a gauge with increments of 1 psi or less.

  • For pressures exceeding 100 psi: Choose a gauge with increments of 2 psi or less.

Conclusion

In conclusion, proper testing and inspection of plumbing systems, including sewer systems, DWV piping systems, and water supply systems, are essential to ensure functionality and compliance with safety standards. The methods highlighted provide reliable ways to verify the integrity of plumbing installations, enhancing their efficiency and safety.