Practice Test Geeks(STSC) Safety Trained Supervisor Construction Practice Test
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Electrical Safety in Construction Flashcards

7 cards from real STSC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Electrical Safety in Construction flashcards as text

  1. Under OSHA 29 CFR 1926.404, what is the maximum allowable ground fault current before a GFCI must trip?

    Answer: 5 milliamps

    GFCIs are designed to trip at 4–6 milliamps, with 5 milliamps being the standard threshold cited by OSHA for construction site protection.

  2. Which condition makes an assured equipment grounding conductor program (AEGCP) an acceptable alternative to GFCIs on a construction site?

    Answer: When a written program with required inspections and records is maintained

    OSHA allows an AEGCP as a GFCI alternative only when the employer maintains a written program that includes required visual inspections and records of testing.

  3. A supervisor notices extension cords are being routed through doorways where doors pinch the cord. What is the primary hazard?

    Answer: Insulation damage that can cause shock or fire

    Pinching or crushing extension cord insulation can expose conductors, creating shock and fire hazards from arcing or direct contact.

  4. What is the minimum safe approach distance for unqualified workers near unguarded energized parts operating at 50 kV?

    Answer: 10 feet

    OSHA 1926.416 requires unqualified workers to stay at least 10 feet away from unguarded energized lines or parts up to 50 kV.

  5. When must a construction supervisor verify overhead power line voltages before allowing equipment to operate nearby?

    Answer: Always, before any work begins on site

    OSHA requires determining line voltage before work begins so the correct safe approach distance can be established and maintained.

  6. Which type of fire extinguisher must be used on an energized electrical fire?

    Answer: Class C (CO2, dry chemical, or halon)

    Class C extinguishers use non-conductive agents such as CO2, dry chemical, or halon, which are safe for energized electrical equipment.

  7. A 120-volt temporary lighting string has a broken lamp socket exposing bare wires. What is the correct immediate action?

    Answer: Replace the string before returning it to service

    Damaged temporary lighting must be removed from service and replaced; tape repairs do not restore the original insulation integrity required by OSHA.

Electrical Safety in Construction Flashcards — STSC Study Cards with Answers