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Working Distances Arc-Flash Calculations per. IEEE 1584-2018

Electrical and Electronics Design and Engineering

Typical Working Distances For Arc-Flash Calculations per. IEEE 1584-2018

Arc-flash design protection is normally based the incident energy level of the working person’s head and torso at the working distance. Typical working distances can be found in the Table below based on the class of equipment. The working distance is used in calculating the incident energy. Alternate working distances may be used depending on the task being performed.

Classes of equipment and typical bus gaps

Equipment Class	Working Distance
	SI units (metric) (mm)	Imperial units (in)
15 kV switchgear	914.4	36
15 kV MCC	914.4	36
5 kV switchgear	914.4	36
5 kV MCC	914.4	36
Low-voltage switchgear	609.6	24
Shallow low-voltage MCCs and panelboards	457.2	18
Deep low-voltage MCCs and panelboards	457.2	18
Cable junction box	457.2	18

Reference:

IEEE 1584-2018

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