After each exposure the product is to have an insulation resistance between live parts and dead metal parts not less than 50,000 ohms. The insulation resistance is to be measured 1 minute after application of the voltage obtained by using the series-voltmeter method, or equivalent means, and a DC circuit. After measurement of the insulation resistance, the complete unit is to comply with the requirements specified in the Dielectric Voltage-Withstand Test, Section 41