Washington Administrative Code › Title 296 - Labor and Industries, Department of › Chapter 296-307 - Safety standards for agriculture › INDOOR OPERATIONS › Part T - Electrical › Section 296-307-36227 - Access and working space for electrical equipment of 600 volts, nominal, or less

Current through Register Vol. 24-14, July 15, 2024
Sufficient access and working space must be provided and
					 maintained about all electric equipment to permit ready and safe operation and
					 maintenance of such equipment.
(1)
				  Unless otherwise indicated, the dimension of the working space in the direction
				  of access to live parts operating at 600 volts or less and likely to require
				  examination, adjustment, servicing, or maintenance while alive must be at least
				  that indicated in the table below. Also, workspace must be at least 30 inches
				  wide in front of the electric equipment. Distances must be measured from the
				  live parts if they are exposed, or from the enclosure front or opening if the
				  live parts are enclosed. Concrete, brick, or tile walls are considered
				  grounded. Working space is not required behind assemblies such as dead-front
				  switchboards or motor control centers where there are no renewable or
				  adjustable parts such as fuses or switches on the back and where all
				  connections are accessible from other directions.
Working Clearances
Nominal voltage
Minimum clear distance for condition
							 (ft)
to ground
(a)
(b)
(c)
0-150
13
13
3
151-600
13
3-1/2
4
Conditions:
(a) 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 guarded by suitable wood or other insulating material. Insulated
								wire or insulated busbars operating at 300 volts or less are not considered
								live parts.
(b) Exposed live parts on one side and grounded
								parts on the other side.
(c) Exposed live parts on both sides of the
								workspace (not guarded as in (a)) with the operator between.
(2) Working space required by this part must
				  not be used for storage. When normally enclosed live parts are exposed for
				  inspection or servicing, the working space, if in a passageway or general open
				  space, must be suitably guarded.
(3) At least one entrance of sufficient area
				  must be provided to give access to the working space about electric
				  equipment.
(4) Where there are live
				  parts normally exposed on the front of switchboards or motor control centers,
				  the working space in front of such equipment must be at least 3 feet.
(5) All working spaces around service
				  equipment, switchboards, panelboards, and motor control centers installed
				  indoors must be adequately lit.
(6)
				  The minimum headroom of working spaces about service equipment, switchboards,
				  panelboards, or motor control centers must be 6 feet 3 inches.
Motor control center
.
An assembly
					 of one or more enclosed sections having a common power bus and principally
					 containing motor control units.
97-09-013, recodified as § 296-307-36227, filed
						4/7/97, effective 4/7/97. Statutory Authority:
						RCW
						 49.17.040,[49.17.]050 and [49.17.]060.
						96-22-048, § 296-306A-36227, filed 10/31/96, effective
						12/1/96.