How to Test a Sewer Per IPC

Air Test

• 1

  Plug each of the laterals.

• 2

  Apply 3.5 pounds per square inch of air pressure to the plumbing section.

• 3

  Monitor the pressure lost after five minutes. To pass the test, no more than one half PSI should be lost at the end of five minutes. Local code may allow for a retest. You can tell how much PSI is lost by how much more psi you have to add to bring the level back up to 3.5 PSI.

Water Exfiltration Test

• 4

  Plug the lateral and riser at the clean-out.

• 5

  Surcharge the line with water until it is level with the foundation grade. The minimum water level must be at least two feet above the lateral invert at the sewer clean-out. If any fixtures are below that level, they must be plugged off for the test and a backwater valve must be installed.

• 6

  After 30 minutes, measure the amount of water that was lost. More than 4 gallons of water loss for a four-inch lateral is a code failure. The city inspector may allow more water loss for larger laterals.