USCG Exam PracticeEngine-room safety and hazardous materials
Under 46 CFR §111.106-3, lighting circuits serving explosion-proof fixtures in an enclosed hazardous space must meet several requirements. Which of the following is specifically required?
- A. The circuit switch and overcurrent device must be located inside the hazardous space for rapid de-energization
- B. A single lighting branch circuit is sufficient provided it is rated for the full connected load
- ✓ The switch and overcurrent protective device must open all ungrounded conductors of the circuit simultaneouslyCorrect
- D. Lighting fixtures must be certified under IEC 60079-18 for Zone 0 locations
Why C is correct
46 CFR §111.106-3(e)(4) requires the switch and overcurrent protective device to open all ungrounded conductors simultaneously. §111.106-3(e)(3) further requires that the switch and overcurrent device NOT be located within the enclosed hazardous space, making option A incorrect. At least two branch circuits are required per §111.106-3(e)(1), making option B incorrect.
Cited:46 CFR §111.106-3