All silencers that require air leak tests will be tested as follows

  1. The silencer will have all openings closed & leak tight.
  2. Air pressure in the silencer will be stabilized at 10 psig and the silencer will hold this pressure for 2 hours.
  3. A thin film Bubble Test Solution #372E manufactured by American Gas & Chemicals Co., 220 Pegasus Ave., Northvale NJ, 07647 will be applied to all weld areas including the nameplate area. The presence of air bubbles in the thin film solution indicates an air leak.
  4. Any leak detection will immediately be repaired and that area re-tested for leaks.