Insulated Hand Tools

Quick Tips #204

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.

General Requirements

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

Commonly Asked Questions

QAre there requirements for periodic retesting of insulated hand tools? A

Although there are not specific requirements for retesting insulated hand tools, in compliance with 29 CFR 1910.335(a)(1)(ii), protective equipment must be maintained in a safe, reliable condition, and should be periodically inspected or tested as required by 1910.137. Most manufacturers suggest inspecting the insulation before each use and having a qualified person perform an annual inspection and certification. To aid the inspection process, some manufacturers offer two-layer insulation that will change color when the insulation has been breached.

QCan I use insulated tools on energized circuits? A

Always follow the manufacturer's recommendations for use. Although insulated hand tools are tested and certified to 1000 volts AC, the testing agencies do not recommend using them on energized circuits. Most insulating tools are designed only for protection from accidental contact with energized circuits.

The Deutsches Institute for Normung (DIN-German Standard)
Klein Tools
American Society for Testing and Materials
International Electrotechnical Commission
Electrical Safeguards for Personnel Protection: 29 CFR 1910.335
Electrical Protective Devices: 29 CFR 1910.137

(Rev. 6/2014)

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Please Note:
The information contained in this publication is intended for general information purposes only and is based on information available as of the initial date of publication. No representation is made that the information or references are complete or remain current. This publication is not a substitute for review of the current applicable government regulations and standards specific to your location and business activity, and should not be construed as legal advice or opinion. Readers with specific questions should refer to the applicable standards or consult with an attorney.

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