Overview
EN ISO 23368:2022 - Anaesthetic and respiratory equipment: Low‑flow nasal cannulae for oxygen therapy - specifies design, safety and performance requirements for low‑flow nasal cannulae used in home care and hospital settings. The standard defines low‑flow cannulae as patient interfaces designed for use with flows ≤ 6 L/min and requires devices to operate normally up to 15 L/min. It does not set requirements to prevent fire propagation in tubing, but it requires a user‑detachable connection to allow fitting of a fire‑activated oxygen shut‑off device.
Key topics and technical requirements
- Scope and definitions
- Applies to low‑flow nasal cannulae (adult, paediatric, neonatal) used for oxygen therapy.
- Defines inlet connector, integral vs user‑detachable cannulae, and oxygen therapy terms.
- Materials and biological safety
- Gas pathways must be assessed for biocompatibility per ISO 18562‑1.
- Design requirements
- Cannulae may be integral with therapy tubing (min. length 1.8 m) or user‑detachable with inlet connector located close to the bifurcation.
- Operation specified for flows ≤15 L/min.
- Flow and resistance
- Therapy tubing resistance: ≤ 0.9 kPa/m at 4 L/min (adult), 3 L/min (paediatric), 2 L/min (neonatal).
- Headset resistance: ≤ 10 kPa at the same respective flows.
- Bending test: flow reduction must not exceed 25% when tubing is bent into a semicircle with diameter three times its smallest outside diameter.
- Connectors and mechanical tests
- Inlet connectors for integral cannulae must be compatible with specified nipple profile and resist detachment under a static internal pressure of (200 ± 10) kPa. Specified engagement forces and torques are used in testing.
- Sterility, packaging and information
- Requirements cover sterility claims, packaging and mandatory manufacturer information supplied with the device.
Applications and who uses this standard
- Manufacturers and product designers of nasal cannulae and oxygen therapy tubing - for design, testing and technical documentation.
- Medical device testing laboratories - to verify resistance‑to‑flow, connector security and bending performance per normative test methods (Annex A/B).
- Procurement and clinical engineering in hospitals and home‑care services - to specify compliant equipment.
- Regulatory bodies and conformity assessors - to assess conformity with European and international requirements for respiratory patient interfaces.
Related standards
Keywords: EN ISO 23368:2022, low‑flow nasal cannulae, oxygen therapy, nasal cannula, resistance to flow, user‑detachable connection, home care, hospital.