Leakage Current Testing of Portable Cord Connected Electrical Tools in the Construction Industry.

[TVH]

Under what conditions should cord connected electrical tools be tested for Current Leakage?
OSHA does not require such testes but NFPA 70B (Recommended Practice for Electrical Equipment Maintenance) states "Portable and cord connected equipment should be periodically tested for the amount of leakage current present to help ensure against shock hazards." ( RE: Par. 17-7 Leakage Current Testing).
Also does a GFCI protected circuit eliminate the need for such testing?
Should such testing be part of an assured grounding conductor program?
Perform the test as part of an incident investigation?
Comments from electrical professional appreciated.

 

[oshaprofessor]

While I’m not a big fan of the latest edition of 70B where major revisions were made and also I’m seeing what I would characterize an overreaction to this new and significantly revised edition.

I’ve conducted forensic electrical fatality and accident investigations for decades and have never had to use my megger (I have one).

According to the latest edition of 70B (2023)

New section “29.3.5* Electrical Testing. When a GFCI or an assured equipment grounding conductor program is not implemented, electrical testing of portable electrical tools and equipment shall be conducted to verify the following, at a minimum:

• Equipment ground from the tool or equipment to the plug ground pin
• Insulation resistance
• Correct polarity”

There are more critically important safety requirements/concerns requiring attention and audits including GFCI’s, the correct type of GFCI (as in weatherproof if exposed to the elements, equipment grounding, etc.

I would suggest not getting caught up in such esoteric electrical tests. I don’t believe very many qualified electrical workers/wiremen/electricians typically have such instruments as meggers, hi-pot testers and the like.

I hope this has helped.