[China Aluminum Network] 1. The bottle body must be tested for airtightness after the hydrostatic test. The test pressure is the nominal working pressure of the cylinder. 2. Bottles are parked in submerged water for one minute under nominal working pressure. No leakage is acceptable. 3. Leakage due to poor assembly quality can be re-tested after rework. 4. The inner surface of the finished bottle should be dry.