ASTM F1417 Low Pressure Air Testing of Sewer Lines - Choice of Methods

[CivilizedPE]

Looking to specify leakage testing of 4" to 12" PVC sanitary sewer lines using low pressure air in accord with ASTM F1417. This standard allows two methods - Constant Pressure Method and Time-Pressure Drop Method.

Which method is more common?
Do contractors have a preference?
Pros and cons of each method?

The jurisdication does not specify one method over the other. Thanks.

 

[bimr]

The time pressure test is more common.

The low pressure test is used to detect leaks in sewers in lieu of using an exfiltration or infiltration test.

The air test is intended to detect defects in the sewer line and establish the integrity of the sewer line under sewer conditions.

Safety procedures should be followed. The pipe plugs will need to be braced during the testing and the bracing should not be removed until the pressure has been reduced to atmospheric. No one shall be allowed to be near the sewer during the testing. A relief valve should be installed with the compressor to prevent over pressurizing the sewer.