CSLB C-46 Solar ContractorSafetyMedium
A solar technician is about to use a portable electric drill on a job site. Which of the following is the most critical safety feature or practice to ensure protection against electric shock?
- AWearing safety glasses while operating the drill.
- BUsing a drill with a keyless chuck.
- CVerifying the drill is double-insulated or properly grounded.
- DEnsuring the drill has a variable speed trigger.
Show answer & explanationAnswer & explanation
Correct answer: C. Verifying the drill is double-insulated or properly grounded.
Double insulation or proper grounding (via a three-prong plug and grounded outlet) are critical safety features that protect against electric shock by providing a path for fault current to safely dissipate, preventing the tool's casing from becoming energized.
Why the other options are wrong
- A. Wearing safety glasses protects against eye injuries from debris, not electric shock.
- B. A keyless chuck is a convenience feature for changing bits, unrelated to electric shock protection.
- D. A variable speed trigger is a operational feature, not primarily a shock protection feature.
Portable Electric Tool Shock Protection
Protection against electric shock from portable electric tools is primarily achieved through double insulation or proper grounding (using a three-prong plug with a grounded outlet or GFCI).
- Double insulation provides two layers of insulating material.
- Grounding creates a low-resistance path for fault currents.
- Ground Fault Circuit Interrupters (GFCIs) also provide shock protection.
- Regular inspection for damaged cords/housing is crucial.
Memory trick: Double or ground, shock won't be found.