- Safety Corner | September 16, 2013
Should a situation arise that leaves you looking for an exit out of harm’s way, your egress path must be secure and clear, and the egress door must function and lead to safety. When performing electrical work, or any type of work for that matter, an effective means of egress can mean the difference between life and death. This appears to be a seemingly simple topic of emergency egress, but one that should not be assumed. Let’s review this topic and uncover topics for you and your team to consider when planning your next electrical project.
Codes and Standards
When thinking about egress and electrical safety, the National Electrical Code (NEC) immediately comes to mind to see what sections help to ensure the installation provides attention to egress. Section 110.26(C), “Entrance to and Egress from Working Space” is the first section that needs to be considered. This section has a minimum requirement of having at least one entrance of sufficient area to provide access to and egress from working space about electrical equipment. There is currently special consideration given to equipment 1,200 Amps and higher and larger than 6 feet wide. But these requirements have not been there since day one. We have to look back to understand some of the history as the facilities we work in are not all built to the latest code.
The history of this section of the Code shows a requirement for at least one entrance of sufficient area beginning with NEC 1965. Back then it was Section 110-16(C). NEC 1978 saw a change to this section placing a different requirement for control panels rated 1,200 Amps or more and of a size over 6 feet wide. This change was such that it called out for an entrance not less than 24 inches wide at each end where reasonably practicable. Proposal number 100 during the NEC 1978 code cycle, initially rejected, sought to require no less than two exits where equipment is over 800 amperes and more than 6 feet wide. This proposal from the Arizona Chapter of the International Association of Electrical Inspectors (IAEI) was submitted with a substantiation that stated that at least two exits were required for this equipment for electrical worker safety. The submitter noted, “Several people have almost burned to death when they were trapped in the back of such equipment rooms with the equipment burning between them and the only way out.” This proposal was rejected with a panel comment noting, “The specific proposal is impractical and gives no guidance as to where the exits should be placed. The subject may deserve further study, and comments would be helpful.” The panel eventually settled on the final accepted language:
“(C) Access and Entrance to Working Space.
At least one entrance of sufficient area shall be provided to give access to the working space about electric equipment. For switchboards and control panels rated 1200 amperes or more and over 6 feet wide, there shall be one entrance not less than 24 inches wide at each end where reasonably practicable.”
This language was in place until NEC 1984 when the “where reasonably practicable” verbiage came under fire and was replaced with some exceptions. The substantiation for the proposals that were accepted at this time noted that these words were vague and often unenforceable. The two exceptions that were added to replace “where reasonably practicable” were:
Exception No. 1: Where the equipment location permits a continuous and unobstructed way of exit travel.
Exception No. 2: Where the work space required by Section 110.16(a) is doubled.
Receiving continued attention, NEC 1987 attempted to address the issue of where the entrance should be located. The substantiation provided for the accepted propo