Page 25 - excerpts ELP

OSHA fOr POwer Delivery
54
NOrTHweST liNeMAN COlleGe
8,500 ft
P-G MAD = 3.85’ P-P MAD = 4.61’
Altitude
ft m
6,500 ft
P-G MAD = 3.65’ P-P MAD = 4.37’
Correction Factor
4,500 ft
P-G MAD = 3.45’ P-P MAD = 4.14’
3000 4000 5000 6000 7000 8000 9000 10000 12000 14000 16000 18000
900 1.00 1200 1.02 1500 1.05 1800 1.08 2100 1.11
2400 1.14 2700 1.17 3000 1.20 3600 1.25 4200 1.30 4800 1.35 5400 1.39
Sea Level
P-G MAD = 3.29’ P-P MAD = 3.94’
20000 6000 1.44
Footnote: If the work is performed at elevations greater than 3000 ft (900 m) above mean sea level, the minimum approach distance shall be determined by multiplying the applicable distance from the OSHA Minimum Approach Distance tables by the correction factor corresponding to the altitude at which work is performed.
Table R-5
2,500 ft
P-G MAD = 3.29’ P-P MAD = 3.94’
The minimum approach distance on this 69 kV circuit increases with altitude. P-G MAD = Phase-to-Ground Minimum Approach Distance
P-P MAD = Phase-to-Phase Minimum Approach Distance