What is the minimum test duration for the water retention test of a shower liner installation?

The minimum test duration for the water retention test of a shower liner installation is established as 15 minutes. This time frame is designed to ensure that the shower liner is properly sealed and capable of effectively holding water without leaks. During this test, the water level must remain constant for the entire duration, indicating that the installation is watertight. If the test were to be shorter, it might not definitively prove the integrity of the liner, as a leak could develop over a longer period of use. Therefore, setting the test duration at 15 minutes strikes a balance between practicality and thoroughness, ensuring that any potential issues can be detected before the installation is finalized.