Electrical Safety Flashcards
7 cards from real ASP 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 flashcards as text
Which of the following best describes the 'arc flash boundary' according to NFPA 70E?
Answer: The distance at which the incident energy equals 1.2 cal/cm², the onset of a second-degree burn
The arc flash boundary is the distance from an arc source at which the incident energy decreases to 1.2 cal/cm², the threshold for a curable second-degree burn.
Under NFPA 70E, an Energized Electrical Work Permit is required when:
Answer: Work must be performed on or near exposed energized electrical conductors and the equipment cannot be de-energized
An Energized Electrical Work Permit is required whenever work must be done on energized conductors that cannot feasibly be de-energized, documenting the justification and controls.
Electrical equipment located in a Class I, Division 1 hazardous location contains:
Answer: Flammable gases or vapors present in ignitable concentrations under normal operating conditions
Class I, Division 1 locations are those where flammable gases or vapors exist in ignitable or explosive concentrations under normal operating conditions.
The primary cause of electrical fires in the workplace is:
Answer: Overloaded circuits, damaged wiring, or loose connections generating heat
Overloaded circuits, deteriorated wiring insulation, and loose connections are the leading causes of electrical fires because they create heat that can ignite nearby combustibles.
What does the 'hierarchy of controls' recommend as the most effective means of protecting workers from electrical hazards?
Answer: Elimination of the hazard by de-energizing equipment before work begins
Elimination (de-energizing the equipment) is the most effective control because it removes the hazard entirely rather than just mitigating exposure to it.
Temporary wiring used on construction sites under OSHA 29 CFR 1926.405 must be protected from damage and:
Answer: Supported and secured in place at intervals not exceeding 10 feet for cables
OSHA requires that temporary wiring on construction sites be supported and secured at intervals not to exceed 10 feet for cables to prevent damage and tripping hazards.
Which PPE is considered the last line of defense against electrical shock and arc flash hazards?
Answer: Arc-rated clothing, face shields, rubber insulating gloves with leather protectors, and safety footwear
Arc-rated clothing, face shields, rubber insulating gloves, and appropriate footwear form the complete PPE ensemble that protects against both shock and arc flash after engineering and administrative controls.