This standard specifies the method for determining the insulation resistivity of vulcanized rubber, applicable to vulcanized rubber with a resistance greater than 10⁸ Ω. The method involves applying a direct current voltage to a rubber specimen under specified temperature and humidity conditions and measuring its resistance to calculate the resistivity, which characterizes its insulation performance. The core instrument for conducting this test is a high-insulation resistance meter. Such instruments (typically professional volume and surface resistivity testers) provide a stable test voltage and accurately measure the weak current passing through the specimen to calculate the resistance and final resistivity. The standard imposes strict requirements on the control of environmental factors, as laboratory temperature and humidity can significantly influence the test results.