CEA Safety Standards & Regulations 5 — Questions and Answers
Question 1: A tagout device alone (without a lockout device) may be used when:
- The equipment has no lockout point
- The employer can demonstrate that tagging provides the same protection as locking, and lockout is not feasible (Correct answer)
- The supervisor authorizes it verbally
- The equipment is rated under 240V
Correct answer: The employer can demonstrate that tagging provides the same protection as locking, and lockout is not feasible
OSHA 1910.147(c)(3) permits tagout-only when the employer proves full employee protection equivalent to lockout, since lockout is always preferred.
Question 2: Which NEC article governs the installation of wiring methods and materials in hazardous (classified) locations?
- Article 210
- Article 300
- Articles 500–516 (Correct answer)
- Article 700
Correct answer: Articles 500–516
NEC Articles 500–516 cover electrical installations in hazardous classified locations where flammable gases, vapors, or dusts may be present.
Question 3: What does the 'incident energy' measurement in an arc flash hazard analysis represent?
- The total current available at a panel
- The thermal energy released at a working distance during an arc flash event, measured in cal/cm² (Correct answer)
- The voltage potential across exposed conductors
- The time it takes for a breaker to trip
Correct answer: The thermal energy released at a working distance during an arc flash event, measured in cal/cm²
Incident energy is the amount of thermal energy (cal/cm²) an arc flash releases at a specific working distance, used to select appropriate PPE.
Question 4: Under OSHA's Electrical Safety standard, who is responsible for ensuring workers have appropriate PPE for electrical work?
- The worker alone
- The equipment manufacturer
- Both the employer and the employee share responsibility (Correct answer)
- NFPA only
Correct answer: Both the employer and the employee share responsibility
OSHA places the primary duty on employers to provide appropriate PPE and training, while employees are responsible for using it correctly.
Question 5: What is the minimum insulation voltage rating required for rubber insulating gloves used when working on 480V circuits?
- Class 00 (500V)
- Class 0 (1,000V) (Correct answer)
- Class 1 (7,500V)
- Class 2 (17,000V)
Correct answer: Class 0 (1,000V)
ASTM F496 Class 0 gloves are rated for use up to 1,000V AC max-use voltage, making them the minimum acceptable choice for 480V work.
Question 6: What does NEC 110.3(B) require when installing listed electrical equipment?
- Equipment must be installed by a licensed electrician only
- Equipment must be installed and used in accordance with its listing and labeling instructions (Correct answer)
- Equipment must be inspected by the AHJ before each use
- Equipment must be re-tested by a third party after installation
Correct answer: Equipment must be installed and used in accordance with its listing and labeling instructions
NEC 110.3(B) mandates that listed or labeled equipment be installed and used in accordance with any instructions included in the listing or labeling.
Question 7: Which OSHA standard specifically addresses electrical safety requirements for the construction industry (as opposed to general industry)?
- 29 CFR 1910 Subpart S
- 29 CFR 1926 Subpart K (Correct answer)
- 29 CFR 1910.147
- 29 CFR 1926.502
Correct answer: 29 CFR 1926 Subpart K
29 CFR 1926 Subpart K covers electrical safety standards specifically for the construction industry, separate from the general industry standard in 1910 Subpart S.
CEA Safety Standards & Regulations 5
A tagout device alone (without a lockout device) may be used when: