This document specifies fire type-testing requirements and a fire type-test method for valves with one or more obturators. It is not applicable to the testing requirements for valve actuators other than manually operated gearboxes or similar mechanisms when these form part of the normal valve assembly. Other types of valve actuators (e.g. electrical, pneumatic or hydraulic) can need special protection to operate in the environment considered in this valve test, and the fire testing of such actuators is outside the scope of this document. This document specifies the measurement and assessment criteria for: a) through-seat leakage; b) external leakage; c) cavity overpressure relief of double seated valves; d) operability. This document specifies the rules whereby the fire-type testing qualification for a valve can be extended to untested sizes, pressure ratings, and materials of construction of the same basic design type. Fire test reports of valves tested according to previous editions of ISO 10497 are acceptable when submitted together with the full and compliant fire test report as per 6.7 of the edition under which it was tested. Additional testing is specified for double seated valves where the body cavity relief valve setting was not recorded in the original fire test report. NOTE For the purposes of this document, the terms fire type-test and fire test are synonymous.