Name one common testing standard for insulating materials.

ASTM D149 is indeed a widely recognized testing standard specifically designed to assess the dielectric strength of insulating materials. This standard outlines the method for determining the dielectric breakdown voltage, which is a critical property for insulators. By evaluating the maximum voltage an insulating material can withstand before failure, ASTM D149 helps in ensuring that materials meet safety and performance requirements in electrical applications. This testing is essential for manufacturers and engineers to select appropriate insulators for various environments and applications, ensuring reliability and safety in electrical systems. The focus of ASTM D149 on dielectric breakdown makes it particularly relevant for anyone working with insulators in electrical engineering.