Spaces around electrical equipment operating at 1,000V or less are covered in two categories: working space around electrical equipment and dedicated spaces for electrical equipment. These categories are located in 110.26 in the National Electrical Code and have been modified in the 2023 edition.
Working space is extremely important in providing safety around electrical equipment. In the 2020 NEC, the introductory text in 110.26 consisted of the following: “Access and working space shall be provided and maintained about all electrical equipment to permit ready and safe operation and maintenance of such equipment.” That introduction has worked well for many years by requiring access and working space for all electrical equipment.
Expanded Code text
In the 2023 NEC, this introductory text was expanded to cover much more than the very basics. The revised first sentence states that “working space, and access to and egress from the working space” must be provided and maintained about all electrical equipment to permit ready and safe operation and maintenance of electrical equipment. This additional of “access and egress from all electrical equipment” is a major step forward in safety.
An additional sentence was added that states “open equipment doors must not impede access to and egress from the working space.” This statement was actually located in 110.26(C)(2) in the 2020 NEC applying to large electrical equipment. The phrase “large electrical equipment” means those rated 1,200A or more and over 6 feet wide or for service disconnecting means installed in accordance with 230.71(B) where the combined ampere rating is 1,200A or more and where the combined width is over 6 feet.
This sentence now stipulates that any electrical equipment with doors cannot impede entrance to or egress from that area and doesn’t just apply to “large” electrical equipment. For example, there were situations where someone was working on an open switchboard and the switchboard located on the opposite side would also have the doors open, resulting in an area where that person could be trapped and could not safely leave that area in case of a mishap. Emergency personnel could also not access that person, if necessary. This addition to the introductory text is important for safety.
“Access or egress is impeded if one or more simultaneously opened equipment doors restrict working space access to less than 24 inches wide and 6 and ½ feet high.”
An additional sentence was added to the introductory text in the 2023 NEC that goes with that requirement. Open doors cannot impede entrance or egress, and it provides dimensions for the required distance between the open doors of opposite equipment: “Access or egress is impeded if one or more simultaneously opened equipment doors restrict working space access to less than 24 inches wide and 6 and ½ feet high.” There are instances in the NEC where these safety requirements do not always provide specific dimensions, so this added text is a necessary for electrical safety.
Also in the 2023 NEC, there was a change in 110.26(A)(4) covering “limited access” areas. This section recognizes “where equipment operating at 1000 volts, nominal, or less to ground and likely to require examination, adjustment, servicing, or maintenance while energized is required by installation instructions or function to be located in a space with limited access.”
An example is electrical equipment, such as an air handler with a fusible disconnecting means located above a drop ceiling. Section 110.26(A)(4)(1) through (A)(4)(3) states (1) there must be an opening in the drop ceiling that is at least 22 inches by 22 inches, (2) the width of the working space at the equipment is at least 30 inches from side to side or the width of the equipment, whichever is greater and (3) all enclosure doors must be capable of opening to 90 degrees.
There have been added restrictions in 110.26(A)(4)(4) in the 2023 NEC, such as where the space in front of any enclosure must be unobstructed to the floor by fixed cabinets, walls or partitions, but space reductions in accordance with 110.26(A)(1)(b) are permitted. A horizontal ceiling structural member or access panel is permitted in this space, provided the location of weight-bearing structural members does not result in a side reach of more than 6 inches to work within the enclosure.
The final change was in a new 110.26(A)(6) as follows: The grade, floor or platform in the required working space must be kept clear, and the floor, grade or platform in the working space must be as level and flat as practical for the entire required depth and width of the working space.
Electrical workers must carefully follow the requirements in 110.26 where laying out electrical equipment rooms with underground raceways, since once the concrete is poured, changes and lawsuits can be very expensive.