Overview
EN ISO 18082:2014 (ISO 18082:2014) defines the dimensions, allocation and marking of non‑interchangeable screw‑threaded (NIST) low‑pressure connectors used in anaesthetic and respiratory equipment for medical gases. Adopted by CEN as a European standard, it applies to NIST connectors intended for operating pressures up to 1 400 kPa and to vacuum systems at pressures not greater than 60 kPa absolute. The standard helps maintain gas specificity and reduce the risk of dangerous cross‑connections in medical gas systems.
Key topics
- Connector scope and allocation
- Specifies gas‑specific allocation of NIST connector types (e.g., oxygen, nitrous oxide, medical air, helium, carbon dioxide, xenon, mixtures, oxygen‑enriched air, surgical tool drive gases, vacuum).
- Provides an allocation table mapping connector references (A1–C24) to gas services.
- Dimensional requirements and tolerances
- Precise dimensional drawings and tabulated tolerances for body, nipple and nut components (indexing diameters, thread form, depths).
- Dimensions for compatible “O” rings including internal and section diameters and recommended hardness.
- Marking and durability
- Requirements for gas identification marking positions and tests for marking durability (visual inspection and measurement to verify compliance).
- Verification and testing
- Compliance to be verified by measurement and visual inspection; surface finish and critical faces are defined to ensure gas tightness and correct engagement.
- Scope exclusions
- Does not cover DISS (Diameter Index Safety System), SIS (Sleeve Indexed System) or quick connectors specified in other standards.
Applications
- Manufacturers of anaesthetic machines, ventilators, pressure regulators, hose assemblies and flow‑meters use this standard when designing or producing NIST low‑pressure connectors.
- Medical device designers and product development teams ensure connector compatibility and patient safety by following the dimensional allocation.
- Biomedical engineers, hospital procurement and maintenance teams rely on the standard to select and verify gas‑specific connectors and to prevent cross‑connection errors.
- Test laboratories and conformity assessors use the dimensional and marking requirements for inspection and certification.
Related standards
- ISO 5359 - low‑pressure hose assemblies for medical gases (referenced)
- ISO 9170‑1 - terminal units and quick connectors (excluded from scope)
- ISO 4135 - terminology for medical gases
- BS 4518 - referenced for “O” ring identification
- Supersedes EN 15908:2010 (European adoption)
EN ISO 18082:2014 is essential for anyone involved in the design, manufacture, testing or maintenance of medical gas connectors seeking to ensure safety, traceability and regulatory compliance.
