Testing and Commissioning of PVC Non-Pressure Pipes
Either water, air or vacuum testing may be performed on non-pressure PVC pipelines, depending on the availability of test water, or the ability to drain the test water away from the pipeline alignment after the testing is completed.
This section refers to the field test procedures for PVC non-pressure pipes detailed in AS/NZS 2032 and should be read in conjunction with that Standard. Where appropriate the test methods in AS/NZS 2566.2 may also be used. Sanitary plumbing installations shall be tested in accordance with the requirements of AS/NZS 3500.2
All sections of the installation should be sealed off and water introduced through a stand pipe to provide a static head of 3 metres above the top point in the PVC pipeline. All openings in the pipeline must be sealed, or plugged, before starting testing.
A riser pipe should be fitted at the top point in the pipeline to allow a minimum water head of 1 metre at this point and a maximum of 5 metres at the lowest point to be applied.
The test water should be introduced evenly into the pipeline and brought up to pressure after allowing all entrapped air to be purged out of the line.
The test pressure should be maintained for a minimum period of 15 minutes and all joints and connections should be inspected for leakage. Any defects detected should be repaired and the pipeline retested
Where water is unavailable, or undesirable, for testing then air testing may be performed.
All openings must be sealed prior to testing, and air pumped slowly into the pipeline until a test pressure of 50KPa is reached.
This test pressure should be maintained for a minimum time of 3 minutes, and if no leaks are detected, or pressure loss observed on the gauge, the air supply control valve should be turned off and the test pressure held for a minimum time of 1 minute.
If the test gauge pressure reading has not fallen below 35KPa after this time, then the test should be discontinued.
Should the test pressure drop below 35KPa after 1 minute, then the pressure should be returned to 50KPa and maintained until a full inspection of the pipeline has been completed. All joints and connections need to be individually inspected for leakage using a solution of water and detergent poured over any suspect joint. If a leak is present, it will cause the detergent solution to bubble, and foam.
All openings must be sealed prior to testing.
An initial vacuum pressure of approximately 27 kPa should be applied and then the vacuum line closed off and the pipe allowed to stabilise for at least 3 minutes. The gauge pressure should be allowed to drop to 23.6kPa and then time recording should be started. The pipeline is deemed to have passed the test if the test vacuum loss is ≤ 7kPa over the period of time specified in the table below.
|Test length (m)|
|Minimum test duration (minutes)|
PVC drainage pipelines are designed to support external loading within the acceptable limits of diameter deflection for structural reasons.
Where this is a critical feature of the installation, then a plug, or proving tool, can be pulled along the pipeline between manholes, or other entry points.
For joints without any protrusions into the pipe bore, the proving plug can be sized to the minimum internal dimension allowed in the design.
Refer to AS/NZS 2566.2 for details of allowable vertical deflections, time factors and calculating the prover plug size.