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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Modal acoustic emission (MAE) Examination Standard for Periodic Inspection and Testing (Requalification) of Composite Overwrapped Pressure Vessels (COPVs)

This document (standard) describes the use of modal acoustic emission (MAE) examination that use during periodic inspection and testing (Requalification) of hoop wrapped and fully wrapped composite transportable gas cylinders and tubes. This standard covers type II, III and IV COPVs, with metallic and non-metallic liners or of lineless construction, intended for compressed and liquefied gases under pressure.

This standard addresses the requalification of composite overwrapped pressure vessels (COPVs) that are designed and constructed in accordance with ISO standards (11119-1, 11119- 2, 11119-3, 11515 and 17519) and COPVs (composite cylinders/tubes) that are listed in DOT special permits (e.g. DOT-SP 14951, DOT-SP 20391).

This standard authorizes requalification of COPVs by using MAE examination in lieu of hydraulic proof pressure testing and internal visual inspection.

For technical question, contact Mr. Mark Toughiry, 202-366-4545.

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Last updated: Wednesday, August 25, 2021