Insulated hand tools, which were a part of OSHA's 1990 guidelines for electrical safety in the workplace, can help prevent worker fatalities when they're used near energized circuits.
Insulated tool sets are individually tested and certified by the manufacturer for specific working conditions. Generally, the maximum rated voltage for insulated tools is 1000 volts AC and 1500 volts DC. When buying insulated hand tools, look for compliance with the International Electrotechnical Commission (IEC), the American Society for Testing and Materials (ASTM) and/or the Deutsches Institute for Normung (DIN-German Standard). The ASTM, IEC and DIN do not test the tools for compliance. Manufacturers do their own testing, but these organizations set the performance requirements for the insulation. The Association of German Electro Technicians (VDE) is an independent agency that tests a sample of each tool to ensure compliance.
Use and Care of Insulated Hand Tools
Keep tools clean and dry
Inspect insulation before each use
If you doubt the integrity of the insulation, destroy the tool or have it retested
Follow the manufacturer's temperature recommendations for use
Have a qualified person inspect and recertify tools annually for safe use
Use other personal protective equipment as necessary