Working Space for Electrical Systems
The NEC is very specific about working area and space requirements. Its
requirements apply particularly when you are working with electrical equipment.
The requirements for proper working space are essential for safety, maintenance,
and usability. They preserve and protect safety in the electrical working space.
They also keep the working space accessible.
Article 110.26 covers the requirements relative to working spaces. According
to Article 110.26(a)(1-3):
All electrical equipment requires at least three feet of clearance in front of it.
Electrical equipment functioning at 600V necessitates 30 inches of working
space in front of it.
There needs to be at least six feet of headway clearance for the equipment.
Some PV installations may involve working in attic spaces. Working in an
attic generally will require wearing PPE, such as breathing mask, eye protection,
CODE
NEC 2011, 110.26(A)(1–3)
(A) Working Space. Working space for equipment operating at 600 volts, nominal, or less to
ground and likely to require examination, adjustment, servicing, or maintenance while energized
shall comply with the dimensions of 110.26(A)(1), (A)(2), and (A)(3) or as required or permitted
elsewhere in this Code.
(1) Depth of Working Space. The depth of the working space in the direction of live parts shall
not be less than that specified in Table 110.26(A)(1) unless the requirements of 110.26(A)(1)(a), (A)
(1)(b), or (A)(1)(c) are met. Distances shall be measured from the exposed live parts or from the
enclosure or opening if the live parts are enclosed.
(2) Width of Working Space. The width of the working space in front of the electrical equip-
ment shall be the width of the equipment or 762 mm (30 in.), whichever is greater. In all cases,
the work space shall permit at least a 90 degree opening of equipment doors or hinged panels.
(3) Height of Working Space. The work space shall be clear and extend from the grade, floor,
or platform to a height of 2.0 m (6 1/2 ft) or the height of the equipment, whichever is greater.
Within the height requirements of this section, other equipment that is associated with the elec-
trical installation and is located above or below the electrical equipment shall be permitted to
extend not more than 150 mm (6 in.) beyond the front of the electrical equipment.
Reprinted with permission from NFPA 70
®
, National Electrical Code
®
, Copyright© 2010, National Fire
Protection Association, Quincy, MA.
CHAPTER 2 Essential Safety Practices for Designing and Installing PV Systems 29
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