An electrician needs to perform maintenance on a 480V panel. What is the minimum approach distance for qualified workers to exposed energized parts?
Correct Answer
A) 2 feet
For qualified workers working on energized equipment between 151V to 750V, OSHA requires a minimum approach distance of 2 feet to exposed energized parts unless proper PPE and training allow closer approach.
Why This Is the Correct Answer
OSHA 29 CFR 1926.95(c)(1) establishes minimum approach distances for qualified workers around energized electrical equipment. For voltages between 151V and 750V (which includes 480V), the minimum approach distance is 2 feet. This safety requirement protects workers from electrical arc flash and shock hazards. The 480V panel falls squarely within this voltage range, making 2 feet the mandatory minimum distance.
Why the Other Options Are Wrong
Option B: 1 foot
4 feet is excessive for this voltage level and applies to much higher voltage systems above 15kV
Option D: 3 feet
1 foot is insufficient for 480V systems and violates OSHA safety requirements for this voltage range
Memory Technique
Think '2 for 480' - the common 480V three-phase systems require 2 feet minimum approach distance
Reference Hint
OSHA 29 CFR 1926.95 - Personal Protective Equipment, Table for minimum approach distances by voltage level
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