Weekly Safety and NEC Industry Standards Training Thank God It’s Friday “Yes Good Friday”
Today its grounding and bonding, electrical shock hazards, and Osha Portable power tool safety.
The difference between an “effective ground-fault current path” and a “ground-fault current path” is the effective ground-fault current path is “intentionally” constructed to provide a low-impedance fault current path to the electrical supply source for the purpose of clearing a ground fault. A ground-fault current path is all of the available conductive paths over which fault current flows on its return to the electrical supply source during a ground fault. Mike Holt
To quickly remove dangerous touch voltage on metal parts from a ground fault, the fault current path must have sufficiently low impedance to the source so that fault current will quickly rise to a level that will open the branch-circuit over current device. Mike Holt
All hand-held powered drills, tappers, fastener drivers, horizontal, vertical, and angle grinders with wheels greater than 2 inches in diameter, disc sanders with discs greater than 2 inches in diameter, belt sanders, reciprocating saws, saber, scroll, and jig saws with blade shanks greater than a nominal one-fourth inch, and other similarly operating powered tools shall be equipped with a constant pressure switch or control, and may have a lock-on control provided that turnoff can be accomplished by a single motion of the same finger or fingers that turn it on. www.osha.gov