ISO 8659:2020 specifies the endurance test necessary to confirm the ability of hand-operated plastics valves to withstand prolonged use, with repeated opening and closure. It does not specify the ability of valves to withstand adverse conditions, in particular those of chemically aggressive fluid media and/or environments, or excessive fluid velocities and cavitation.
NOTE Concerning the chemical aggression of the materials, a classification table is reported in ISO/TR 10358 [1] .
This document includes values of the parameters necessary for the proper performance of the endurance test, with the reservation that the parameters are different in particular product standards (see 5.1).