Overview
EN ISO 20484:2017 - Non‑destructive testing - Leak testing - Vocabulary (ISO 20484:2017) is a harmonized CEN/ISO vocabulary that defines the terms and definitions used in leak testing. Its scope is explicitly to provide clear, standardized terminology for leak testing methods, phenomena and measurement quantities so that specifications, test reports and procurement documents are unambiguous across industries and countries.
Key topics and technical content
The standard organizes and defines terminology across several technical areas:
- Atomic/molecular structure (e.g., concentration, ionization potential)
- Pressure and vacuum (e.g., atmospheric pressure, partial pressure)
- Gas–solid interaction (e.g., gettering, permeation, permeability coefficient)
- Properties and flow of gases (e.g., ideal gas, conductance, flow rate, pV‑throughput)
- Gas leakage types and measures (e.g., leak, orifice leak, capillary leak, molecular leak, viscous leak, leakage rate, total leakage rate, standard leakage rate, virtual leak)
- Test techniques, equipment and procedures (vocabulary covering methods, instruments, calibration and performance limits)
Important, well-defined measurement concepts such as pV‑throughput (a common way to express leakage rate) and conductance are included, enabling consistent reporting of leak performance and test outcomes.
Practical applications and users
EN ISO 20484:2017 is primarily a vocabulary resource but delivers practical value by:
- Ensuring consistent language in test specifications, acceptance criteria and certification documents.
- Reducing ambiguity when selecting leak test methods or when communicating results between labs, manufacturers and clients.
- Supporting training materials, test procedures and software where correct terminology is essential.
Typical users:
- NDT and leak‑testing engineers and technicians
- Quality assurance and compliance managers
- Test laboratories and calibration services
- Design and manufacturing teams in aerospace, automotive, medical devices, refrigeration, vacuum systems, packaging, petrochemical and energy sectors
- Standards writers and procurement specialists
Related standards
- EN ISO 20484:2017 supersedes EN 1330-8:1998 and is part of the broader EN 1330 / NDT terminology family (EN 1330-1, EN 1330-2, etc.).
- It was prepared in collaboration between ISO TC 135 (NDT) and CEN/TC 138 (Leak testing) and is published as EN ISO 20484:2017 in the CEN catalogue.
Using EN ISO 20484:2017 helps organizations adopt consistent, internationally recognized terminology for leak testing, improving clarity in testing programs, contractual documents and regulatory submissions.
