Determine air leakage by measuring the size of a bubble formed over a specified period of time.

A 25.4 mm (1.0 in) bubble formed over 5 seconds is equivalent to 100 standard cubic centimeters per minute (sccm). A 25.4 mm (1.0 in) bubble formed over 3 seconds is equivalent to 175 sccm.

Use a soap solution in order to perform all air leakage tests. Using a soap solution allows a bubble to form at the site of the air leak, giving a visual aid for diagnosing the air loss rate.