Stumped by the Code? NEC Rules for Access to and Egress from Working Space of Large Equipment

All questions and answers based on the 2020 NEC.

Q. What is the Code rule for access to and egress from working space of large equipment that contains overcurrent devices?

A. Requirements on access to and egress from a working space are outlined in Sec.110.26(C).

(1) Minimum Required. At least one entrance of sufficient area must provide access to and egress from the working space.

Note: Check to see what the authority having jurisdiction (AHJ) considers “sufficient area.” Building codes contain minimum dimensions for doors and openings for personnel travel.

(2) Large Equipment. For large equipment that contains overcurrent devices, switching devices, or control devices, an entrance to and egress from the required working space not less than 24 in. wide and 6½ ft high is required at each end of the working space. This requirement applies for either of the following conditions:

(1) Where equipment is more than 6 ft wide rated 1,200A or more (Fig. 1 below).

Fig. 1. Equipment containing overcurrent devices or switching devices 1,200A or more and over 6 ft wide requires an entrance for the required working space not less than 24 in. wide and 6 1/2 ft high at each end of the working space. — **Fig. 1.** Equipment containing overcurrent devices or switching devices 1,200A or more and over 6 ft wide requires an entrance for the required working space not less than 24 in. wide and 6 1/2 ft high at each end of the working space.

(2) Where the service disconnect is more than 6 ft wide and where the combined ampere rating is 1,200A

Open equipment doors must not impede the entry to or egress from the working space.

A single entrance for access to, and egress from, the required working space is permitted where either of the following conditions are met:

(a) Unobstructed Egress. Where the location permits a continuous and unobstructed way of egress travel (Fig. 2 below).

Fig. 2. The electrical contractor is also responsible for ensuring that panic hardware is installed where required. — **Fig. 2.** The electrical contractor is also responsible for ensuring that panic hardware is installed where required.

(b) Double Working Space. Where the required working space depth is doubled, and the equipment is located so the edge of the entrance is no closer than the required working space distance.

The requirement for a path of egress with the door open may require wider aisle space. The Code does not give specific guidance as to the required width of the egress path, but the egress door must be at least 24 in. wide. It would be reasonable to ensure the aisle has a width equal to the door plus 24 in. Doors that open more than 90° would be ideal for providing more space for egress.

(3) Fire Exit Hardware on Personnel Doors. Where equipment rated 800A or more that contains overcurrent devices, switching devices, or control devices is installed and there is a personnel door(s) intended for entrance to and egress from the working space less than 25 ft from the nearest edge of the working space, the door(s) are required to open in the direction of egress and be equipped with listed panic or listed fire exit hardware on personnel door(s) for entrance to, and egress from, the working space. Such doors must open in the direction of egress.

Notes:

History has shown that electricians who suffer burns on their hands in electrical arc flash or arc blast events often cannot open doors equipped with knobs that must be turned or those that must be pulled open.
Since this requirement is in the NEC, the electrical contractor is responsible for ensuring that panic hardware is installed where required. Some are offended at being held liable for nonelectrical responsibilities, but this rule is designed to save the lives of electricians. For this and other reasons, many construction professionals routinely hold “pre‑construction” or “pre‑con” meetings to review potential opportunities for miscommunication — before the work begins.
The minimum requirement to provide listed panic hardware at or above 800A shouldn’t overshadow the importance to perform a risk assessment to incorporate specific room design, equipment layout, and egress accessibility.

These materials are provided to us by Mike Holt Enterprises in Leesburg, Fla. To view Code training materials offered by this company, visit www.mikeholt.com/code.