Overview
EN ISO 10960:2018 (ISO 10960:2017) specifies a standardized method to assess the resistance of rubber and plastics hoses to the deleterious effects of atmospheric ozone under dynamic conditions. The method is applicable to hoses with bore diameters up to and including 25 mm and is intended to support durability evaluation, quality control and compliance with regulatory or procurement requirements.
Key Topics
- Scope and applicability: method applies to rubber and plastic hoses with bore ≤ 25 mm and assesses cover cracking during reverse bending under ozone exposure.
- Principle: the hose cover in a crescent position during reverse bending is exposed to controlled ozone and periodically examined for cracking.
- Apparatus:
- Ozone cabinet with generation and monitoring per ISO 1431-1.
- Test piece holder enabling flexing at the required frequency (see ISO 1431-1, clause 5.6).
- All apparatus within the cabinet must be made from materials that do not absorb or decompose ozone.
- Test piece dimensions:
- Free length L calculated as L = 20 × d (where d = outside diameter).
- Mounting geometry: key distances A = 10d and B = 5d; piston curvature R per figure in the standard.
- Conditioning:
- No test within 24 h of manufacture; for comparability follow ISO 23529 for conditioning time.
- Mounted test pieces are conditioned 48 h in an ozone-free atmosphere at standard temperature in darkness or subdued light.
- Test conditions and procedure:
- Ozone concentration: (50 ± 5) pphm by volume.
- Temperature: 40 °C ± 2 °C.
- Exposure period: 72 h (with intermediate examinations at 2 h, 4 h, 24 h, 48 h and 72 h).
- Flexing frequency: 0.3 Hz ± 0.03 Hz. Piston travel and return position specified to ensure complete unloading on return stroke.
- Observation: examine samples under ×2 magnification while mounted; record crack nature and first-observed time.
Applications
- Product development: compare formulations or cover compounds for ozone resistance under realistic dynamic strain.
- Quality control: batch verification to confirm consistent ozone resistance across production runs.
- Procurement and compliance: provide objective test evidence for specifications requiring ozone resistance for hoses used in automotive, industrial or fluid-transfer applications.
Related Standards
- ISO 1431-1 - Resistance to ozone cracking: static and dynamic strain testing (referenced for ozone cabinet, monitoring and apparatus details).
- ISO 23529 - Conditioning and preparation of test pieces prior to physical testing.
- ISO 8330 - Vocabulary for rubber and plastics hoses and hose assemblies (terms and definitions used).
Test Report Essentials
Per EN ISO 10960:2018, the test report shall include:
- Reference to ISO 10960:2017/EN ISO 10960:2018;
- Identification details of the hose tested;
- Test conditions (ozone concentration, temperature, exposure period);
- Whether cracks were observed, their nature and time of first observation;
- Date of test.
This standard provides a repeatable, documented approach to assess ozone resistance of small-bore hoses and to support product selection, development and conformity assessment.
