110.26(3)
(C) Entrance to and Egress from Working Space. (1) Minimum Required. At least one entrance of sufficient area shall be provided to give access to and egress from working space about electrical equipment.
The requirements in this section are intended to provide access to electrical equipment. However, the primary intent is to provide egress from the area so that workers can escape if there is an arc-flash incident.
(2) Large Equipment. For equipment rated 1200 amperes or more and over 1.8 m (6 ft) wide that contains overcurrent devices, switching devices, or control devices,
there shall be one entrance to and egress from the required working space not less than 610 mm (24 in.) wide and 2.0 m (6? ft) high at each end of the working space.
A single entrance to and egress from the required working space shall be permitted where either of the conditions in
110.26(C)(2)(a) or (C)(2)(b) is met.
(a)
Unobstructed Egress. Where the location permits a continuous and unobstructed way of egress travel, a single entrance to the working space shall be permitted.
(b)
Extra Working Space. Where the depth of the working space is twice that required by
110.26(A)(1), a single entrance shall be permitted. It shall be located such that the distance from the equipment to the nearest edge of the entrance is not less than the minimum clear distance specified in
Table 110.26(A)(1) for equipment operating at that voltage and in that condition.
