This document specifies five methods for determining the ozone resistance of the outer layer of hoses: Method 1: for inner diameters up to and including 25 mm, carried out on the hose itself; Method 2: for inner diameters over 25 mm, which is carried out on a test specimen from the hose wall; Method 3: for inner diameter over 25 mm, which is carried out on a test specimen from the outer layer; Method 4: for all inner diameters, which is carried out on the hose itself; Method 5: for all inner diameters, performed on expandable hoses, e.g. B. on textile-reinforced hoses. NOTE For hoses with built-in hose fittings from which it is not possible to remove test specimens, the determination of ozone resistance may be carried out using test sheets made of the appropriate polymer mixture and the same degree of vulcanization on plates in accordance with ISO 1431-1.
EN ISO 7326:2016 Referenced Document
ISO 1431-1:2012 Rubber, vulcanized or thermoplastic - Resistance to ozone cracking - Part 1: Static and dynamic strain testing
ISO 23529:2010 Rubber - General procedures for preparing and conditioning test pieces for physical test methods
ISO 8330:2014 Rubber and plastics hoses and hose assemblies - Vocabulary
EN ISO 7326:2016 history
2016EN ISO 7326:2016 Rubber and plastics hoses - Assessment of ozone resistance under static conditions
2008EN ISO 7326:2008 Rubber and plastics hoses - Assessment of ozone resistance under static conditions [Superseded: CEN EN 27326]