Safety personnel designated to support electrical safety programs should be knowledgeable and trained at levels commensurate with their duties.

2.9 WORKING SPACE AROUND ELECTRICAL EQUIPMENT

Working space around electrical enclosures or equipment shall be adequate for conducting all anticipated maintenance and operations safely, including sufficient space to ensure safety of personnel working during emergency conditions and workers rescuing injured personnel. Spacing shall provide the dimensional clearance (discussed in the following subsections) for personnel access to equipment likely to require examination, adjustment, servicing, or maintenance while energized. Such equipment include panelboards, switches, circuit breakers, switchgear, controllers, and controls on heating and air conditioning equipment.

These clearances shall be in accordance with OSHA, NESC, and NEC. These working clearances are not required if the equipment is not likely to require examination, adjustment, servicing, or maintenance while energized. However, sufficient access and working space is still required.

2.9.1 ELECTRICAL EQUIPMENT RATED AT 600 VOLTS OR LESS

A minimum working space 30 in. wide shall be provided in front of electrical equipment rated at 600 V or less. This provides room to avoid body contact with grounded parts while working with energized components of the equipment. The 30-in.-wide space may be centered in front of the equipment or can be offset. The depth of the working space shall be clear to the floor [See NEC 11016(a)]. Where rear access is required to work on deenergized parts, a minimum of 30 inches shall be provided. There shall be clearance in the work area to allow at least a 90-degree opening of equipment doors or hinged panels on the service equipment. Working spaces may overlap. The depth of the working space shall be 3 ft, 3 1/2 ft, or 4 ft, depending upon existing conditions. The conditions are as follows:

Condition 1: These are exposed live components on one side of a space and ungrounded parts on the other side.

Condition 2: The electrical equipment is mounted or set on one wall, and the wall on the opposite side is grounded. If the qualified worker should accidentally contact the conductive wall while touching live components, a circuit would be completed to ground and a fatal shock might occur.

Condition 3: The electrical equipment is mounted or set on one wall, and additional electrical equipment is mounted or set on the opposite side of the room. There are live components on both sides of the room. The qualified worker might accidentally make contact with live components and be in series with a hot phase and the grounded metal of the electrical equipment, which could produce a fatal shock.

See Figure 2-3 for the clearance requirements in front of electrical equipment rated 600 V or less. See NEC Section 110-16(a) Exception 1 for clearance requirements in the rear of electrical equipment.

Figure 2-3. Minimum clearances in front of electrical equipment (600 V or less). 2-13