Understanding General Requirements of the NEC, Part 13

Article 110 provides general requirements for all installations. Part II provides the requirements for systems operating at 1,000V (nominal) or less. Section 110.26(A) covers working spaces about equipment. Those spaces must be kept clear [Sec. 110.26(B)]. They cannot be used for storage. The floor, grade, or platform of such a space must be as level and flat as practical for the entire depth and width of that space.

Adequate space for ingress and egress is also generally required. For any working space about equipment, there must be at least one entrance of sufficient area to provide ingress and egress [Sec. 110.26(C)(1)].

For large equipment that contains devices for overcurrent, switching, or control, you need at least on entrance that is at least 24 in. wide and 6.5 ft high — at each end of the working space [Sec. 110.26(C)(2)]. But that width goes to 3 ft minimum, if the equipment is rated 1200A or more or the combined ampere rating of the service disconnect is 1200A or more.

You can get by with a single entrance for that space, if your installation meets either of these two conditions:

1. The location permits a continued and unobstructed way of egress travel.
2. The working space depth is at least twice what’s required by Sec. 110.26(A)(1).

Have you heard of the 90-degree door rule? It’s in Sec. 110.26(C)(3). It applies to personnel doors for equipment rated 800A or more, but nothing stops you from applying it to all equipment to the practical extent. The door has to swing out at least 90 degrees, and it must be equipped with panic hardware or listed fire hardware. One reason for this is if you injure your hands, you don’t have to fumble with doorknob to get out.

You’ll find a basic illumination requirement in Sec. 110.26(D). It applies to all indoor working spaces about service equipment, switchboards, switchgear, enclosed panelboards, and motor control centers. It doesn’t specify how much light, but when we go back to Sec. 90.1 and read the words “practical safeguarding of people” it doesn’t need to. Typically, ambient light will be inadequate for this purpose.

Light it up so that people can easily see to work. Use a combination of light sources to achieve the best effect (zero shadows); LED strip lighting can help with that. Keep in mind that the average electrician today is over 40 years old and the progressive presbyopia that increases the need for light starts a little before that.

OSHA has workplace lighting requirements [29CFR1926.1915.82] and you can use those as a starting point. Stop to think whether your goal to check off a compliance box or to ensure that your electricians have enough light to work accurately, efficiently, and productively. Electricians should not have to squint, incur eye fatigue midday, or work by flashlight.

Lighting sources need to be properly located and their light properly aimed. You might use a mix of diffused and direct light. You may need to experiment using portable lights, getting feedback from crews as they work with the light that’s provided. They need to be able to easily spot things that are out of place or not quite right, such as water tracks on a cabinet wall, arc marks on a breaker body, or a discolored conductor jacket. Without a flashlight.

If you fail to light to this degree, will your AHD penalize you or will OSHA fine you? Probably not, but there will be other costs, such as increased mistakes and reduced productivity.