Q. According to the 2008 NEC, one of the reasons why flame resistant clothing and equipment is required is to protect qualified persons from the hazard of ______________?

  1. A gas discharge from an interrupting device.
  2. A non-insulated tool being dropped onto energized parts.
  3. The additional hazard of circuits operating at over 600 volts.
  4. Older equipment that is not properly maintained.

Answer: A

As per 490.39, "gas discharged during operating of interrupting devices shall be directed so as not to endanger personnel." One can also see why NFPA 70E, Standard for Electrical Safety in the Workplace, may require flame resistant clothing and equipment when operating power disconnect switches and circuit breakers operating at more than 600V.

Owen is the owner and president of National Code Seminars and the holder of master electrician certifications in 46 states. He can be reached at necexpert@aol.com.