During an air test on a new construction, which condition could cause the test to fail?

During an air test on a new construction, which condition could cause the test to fail?

• A. Sagging pipe
• B. Pipe too short
• C. Rubber ends blocking pipes failed
• D. Could cause the air test to fail

Answer: (B)

The test checks how well a sealed pipe section holds air under pressure. It relies on having a properly sized, continuous length of pipe with end plugs that seal well so any leak would cause a measurable drop in pressure. If the pipe is too short, you don’t have enough length to properly install and seal the test ends, and the small amount of air can be lost or misread more easily. The result is an unstable or invalid reading, making the test fail even if longer sections might have passed. In other words, a shorter-than-required length compromises the integrity of the pressure test by giving a too-small, improperly sealed volume to work with. The other scenarios could cause issues, but they don’t inherently render the test invalid in the same way a too-short run does: sagging pipe might create stress on joints but isn’t an automatic cause of pressure loss; rubber end plugs failing would be a different failure mode; and saying the test could cause failure is not a specific cause.

The test checks how well a sealed pipe section holds air under pressure. It relies on having a properly sized, continuous length of pipe with end plugs that seal well so any leak would cause a measurable drop in pressure.

If the pipe is too short, you don’t have enough length to properly install and seal the test ends, and the small amount of air can be lost or misread more easily. The result is an unstable or invalid reading, making the test fail even if longer sections might have passed. In other words, a shorter-than-required length compromises the integrity of the pressure test by giving a too-small, improperly sealed volume to work with.

The other scenarios could cause issues, but they don’t inherently render the test invalid in the same way a too-short run does: sagging pipe might create stress on joints but isn’t an automatic cause of pressure loss; rubber end plugs failing would be a different failure mode; and saying the test could cause failure is not a specific cause.