CSLB C-20 HVAC ContractorControls, Electrical and SafetyMedium

A technician must perform diagnostic work on an energized 480-volt panel where de-energization is not feasible due to critical operations. Per Cal/OSHA electrical safety requirements, what must be used to protect the technician?

  1. AAppropriate arc-rated PPE and insulated tools rated for the voltage and incident energy level
  2. BA second technician standing by with a fire extinguisher
  3. CA rubber floor mat with no other protective equipment
  4. DStandard leather work gloves and safety glasses only
Show answer & explanation

Correct answer: A. Appropriate arc-rated PPE and insulated tools rated for the voltage and incident energy level

Cal/OSHA requires that when work on energized equipment cannot be avoided, technicians must use arc-rated PPE and insulated tools rated for the specific voltage and calculated incident energy exposure, following an established energized work permit process. Leather gloves alone, a mat by itself, or a bystander with an extinguisher do not meet the required protective standard for live electrical work.

Why the other options are wrong

  • B. A standby person with an extinguisher doesn't prevent electrical injury.
  • C. A floor mat alone doesn't protect against arc flash or direct contact.
  • D. Standard gloves and glasses provide no arc-flash or shock protection.

Energized Work PPE

Cal/OSHA requires arc-rated PPE and insulated tools rated for the specific voltage and incident energy when work on energized equipment cannot be de-energized.

  • Energized work requires a documented justification/permit
  • PPE rating must match calculated incident energy
  • Insulated tools prevent direct contact shock
  • De-energization is always preferred when feasible

Memory trick: Can't kill the power? Suit up in arc-rated armor.

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