A construction company is implementing a new safety policy for the use of portable electric tools. Which of the following statements correctly describes a mandatory OSHA requirement for protecting workers from electric shock when using these tools?
- AAll portable electric tools must be double-insulated, making grounding unnecessary.
- BOnly tools operating above 120 volts require either grounding or double insulation.
- CAll portable electric tools must be powered by a Ground-Fault Circuit Interrupter (GFCI) unless they are specifically approved for ungrounded use.
- DAssured Equipment Grounding Conductor Program is only required on construction sites where GFCIs are not feasible.
Show answer & explanationAnswer & explanation
Correct answer: C. All portable electric tools must be powered by a Ground-Fault Circuit Interrupter (GFCI) unless they are specifically approved for ungrounded use.
OSHA 1926.404(b)(1)(ii) requires that all 120-volt, single-phase, 15- and 20-ampere receptacle outlets on construction sites, which are not part of the permanent wiring of the building or structure and which are in use by employees, shall have approved ground-fault circuit interrupters for personnel protection. An alternative is an Assured Equipment Grounding Conductor Program (AEGCP). Therefore, GFCI protection (or AEGCP) is mandatory. Double insulation is an alternative to grounding, not a universal requirement that eliminates the need for GFCI.
Why the other options are wrong
- A. Not all tools are double-insulated, and if they are not, they must be grounded. Even double-insulated tools benefit from GFCI protection on construction sites.
- B. Grounding or double insulation is required for all portable electric tools, regardless of voltage, to protect against shock.
- D. The Assured Equipment Grounding Conductor Program is an *alternative* to using GFCIs, not a program only for when GFCIs are not feasible. One or the other is required for most portable electric tools.
Construction Site Electric Tool Shock Protection
On construction sites, portable electric tools must be protected from electric shock by either Ground-Fault Circuit Interrupters (GFCIs) or an Assured Equipment Grounding Conductor Program (AEGCP).
- GFCIs trip circuits upon detecting a ground fault.
- AEGCP involves regular inspection and testing of grounding paths.
- This protection is in addition to the tool's inherent grounding or double insulation.
Memory trick: GFCI or Grounding Program, that's the construction site's shock anthem!