Overview
ISO/TS 19016:2019 - Modal acoustic emission (MAE) testing for periodic inspection of composite gas cylinders - defines a technical specification for using modal acoustic emission (MAE) as a non‑destructive examination (NDE) method during periodic inspection and testing of hoop‑wrapped and fully wrapped composite cylinders and tubes. It applies to composite constructions with aluminium‑alloy, steel or non‑metallic liners, or linerless designs, intended for compressed and liquefied gases under pressure. Unless otherwise stated, “cylinder” covers both cylinders and tubes.
MAE captures broadband acoustic waveforms generated by damage mechanisms (fibre tow breakage, delamination, rubbing, cracking) and uses waveform modal analysis to identify damage that can compromise burst strength. MAE testing is intended for in‑service periodic inspection - not for new production qualification.
Key Topics
- MAE operational principles: detection, capture and modal analysis of acoustic events to characterise damage type.
- Personnel qualification: references ISO 9712 for NDT personnel competence requirements.
- Equipment & calibration: requirements for broadband piezoelectric sensors, preamplifiers, rolling‑ball impact and absolute sensor calibration, and MAE data acquisition system calibration.
- Testing procedure: sensor coupling and positioning, attenuation measurement, system settings and sampling rates, pressurisation methods (hydraulic or pneumatic) to the cylinder’s design test pressure, and repeating tests for validity.
- Data interpretation: noise filtering (EMI, mechanical rubbing, flow noise, leakage), waveform analysis, background energy and background energy oscillation (BEO) indicators.
- Acceptance/rejection: evaluation criteria and analysis procedures to determine when a cylinder is unserviceable; guidance on test reporting and rendering cylinders unserviceable.
Applications
- Periodic inspection of composite gas cylinders and tubes used in transportation, industrial gas supply, SCBA (self‑contained breathing apparatus), and specialty gas systems.
- Test laboratories and NDT service providers performing regulatory inspections or fleet maintenance.
- Cylinder manufacturers and OEMs incorporating MAE into maintenance programs when authorized by competent authorities.
- Regulators and competent authorities evaluating alternative NDE methods for periodic testing regimes.
Who uses it: NDT technicians, inspection engineers, maintenance managers, test laboratories, competent authorities and standards compliance teams.
Related Standards
ISO/TS 19016:2019 provides a practical, physics‑based MAE framework to improve detection of structural damage in in‑service composite cylinders and to support safe, standards‑based inspection decisions.