Cal. Code Regs. tit. 8, § 2340.16
(a) Space about electric equipment.
Sufficient access and working space shall be provided and maintained about all electric equipment to permit ready and safe operation and maintenance of such equipment.
(b) Work Space. Working space for equipment likely to require examination, adjustment, servicing, or maintenance while energized shall comply with the following dimensions, except as required or permitted elsewhere in these Orders.
(1) Depth. The depth of the working space in the direction of access to live parts shall not be less than indicated in Table 2340.16 unless permitted elsewhere in these orders.
Distances shall be measured from the live parts if they are exposed or from the enclosure front or opening if they are enclosed.
(2) Width. In addition to the dimensions of depth shown in Table 2340.16, the width of the workspace in front of the electric equipment shall not be less than the width of the equipment or 30 inches, whichever is greater.
In all cases, the workspace shall be adequate to permit at least a 90 degree opening of equipment doors or hinged panels.
(3) Height. The work space shall be clear and extend from the grade, floor, or platform to the height required by subsection (f) of this section. However, other equipment associated with the electrical installation and located above or below the electric equipment may extend not more than 6 in. (153 mm) beyond the front of the electric equipment.
Table 2340.16. Minimum Depth of Clear Working Space at Electrical Equipment, 600 V or Less
Nominal
Minimum Clear Distance
Voltage to
Condition 1
Condition 2
Condition 3
Ground
Feet
Meters
Feet
Meters
Feet
Meters
0-150
3*
0.9
3*
0.9
3
0.9
151-600
3*
0.9
3.5
1.0
4
1.2
Notes to Table 2340.16:
Where the “Conditions” are as follows:
Condition 1--Exposed live parts on one side and no live or grounded parts on the other side of the working space, or exposed live parts on both sides effectively guarded by suitable wood or other insulating materials. Insulated wire or insulated busbars operating at 300 volts or less shall not be considered live parts.
Condition 2--Exposed live parts on one side and grounded parts on the other side. Concrete, brick, or tile surfaces shall be considered as grounded surfaces.
Condition 3--Exposed live parts on both sides of the work space (not guarded as provided in Condition (1)) with the operator between.
Exceptions:
*1. Minimum clear distances may be 2.5 ft. (0.7 m) for installations built before April 16, 1981.
(d) Entrance and Access to Workspace. At least one entrance of sufficient area shall be provided to give access to the working space about electric equipment.
(1) For equipment rated 1,200 amperes or more and over 6 feet (1.83 m) wide, containing overcurrent devices, switching devices, or control devices, there shall be one entrance not less than 24 inches (610 mm) wide and 6 feet 6 inches (1.98 m) high at each end of the workspace, except that:
(e) Illumination. Portable or fixed illumination, suitable for the nature of the work being performed, shall be provided when working on electrical equipment. The light fixtures and their control points shall be so arranged that persons operating light switches, replacing lamps or making repairs on the lighting system will not be endangered by energized parts of other equipment.
Exception: Additional lighting fixtures are not required where the working space is illuminated by an adjacent light source. In electric equipment rooms, the illumination may not be controlled by automatic means only.
(f) Headroom. The minimum headroom of working space about service equipment, switchboards, panelboards and motor control centers, which require manual operation or where there are energized parts exposed at any time, shall be as follows:
(g) For installations built on or after May 5, 2008, switchboards, panelboards, and distribution boards installed for the control of light and power circuits, and motor control centers shall be located in dedicated spaces and protected from damage.
(1) Indoor. For indoor installation, the dedicated space shall comply with the following:
(D) Control equipment that by its very nature or because of other requirements in these Orders must be adjacent to or within sight of its operating machinery is permitted in the dedicated space.
Note to subsection (g)(1): A dropped, suspended, or similar ceiling that does not add strength to the building structure shall not be considered a structural ceiling.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
1. Repealer and new section filed 3-23-79; effective thirtieth day thereafter (Register 79, No. 12). For history of former section, see Register 75, No. 42.
2. Amendment of Table 2340.16 and Plate 2340.16(a)(1) filed 2-1-83; effective thirtieth day thereafter (Register 83, No. 6).
3. Editorial correction filed 11-2-83 (Register 83, No. 45).
4. Editorial correction of Table 2340.16 filed 11-3-83 (Register 83, No. 45).
5. Amendment of Table 2340.16, subsections (c)-(f) and Plate 2340.16(a)(2) filed 8-27-86; effective thirtieth day thereafter (Register 86, No. 37).
6. Amendment of section, repealer of Plate 2340.16(a)(2), and amendment of Note filed 5-5-2008; operative 5-5-2008. Submitted to OAL for printing only pursuant to Labor Code 142.3(a)(3) (Register 2008, No. 19).
7. Amendment of subsection (b)(2), repealer of subsections (b)(2)(A)-(B) and amendment of subsection (b)(3) filed 4-6-2010; operative 5-6-2010 (Register 2010, No. 15).