Pennsylvania Code › Title 34 - LABOR AND INDUSTRY › Part I - Department of Labor and Industry › Chapter 39 - SAFETY STANDARDS-GENERAL › Subchapter B - ELECTRIC SAFETY › FUSES AND OTHER CUT-OUTS, SWITCHES AND CONTROLLERS › Section 39.160 - Guarding live parts of switches and automatic cut-outs not installed on switchboards

Current through Register Vol. 54, No. 28, July 13, 2024
(a)
Above 750 volts.
Switches interrupting circuits over 750 volts
					 shall be operated by means of remote control mechanisms or be provided with
					 suitable casings protecting the operator from danger of contact with
					 current-carrying parts, except as provided in subsection (d), for switches
					 requiring only infrequent attention and located in enclosures from which even
					 the operator is normally excluded. The control devices for switches shall
					 indicate whether switches are open or closed. Lever operated, circuit breaker
					 type switches should be equipped with indicating devices to show, other than by
					 the position of the handles, whether they are open or closed. Automatic
					 cut-outs not suitably isolated by elevation shall be of an incased type or be
					 provided with suitable enclosures for current-carrying parts. Large capacity,
					 high voltage oil switches should, where practicable, be placed away from the
					 operator and operated by remote (or lever) controls, since the blowing up of
					 the oil containers may cause serious injuries to persons in the vicinity. For
					 the purpose of this section voltage in excess of 750 will be included as below
					 750 where the excess is for the purposes of regulation only.
(b)
Below 750 volts.
Switches interrupting circuits under 750 volts shall be operated by means of
					 remote control mechanisms or be incased during ordinary operation or be
					 provided with insulating handles and insulating guard disks or shields arranged
					 so as to make it unlikely that the hand may come in contact with live parts.
					 Switches below 300 volts to ground may be exempted from the requirements of
					 this subsection.
(c)
Platforms or mats.
Where live parts of switches or automatic
					 cut-outs operating at over 300 volts to ground are not remotely controlled, or
					 provided with enclosing guards effective during ordinary operation or
					 adjustment, or isolated by elevation, suitable insulating floors, mats, or
					 platforms shall be provided on which the operator shall stand while operating
					 the switches or adjusting the automatic cut-outs. Reference should also be made
					 to §
											39.105(b)
					 (relating to guarding live parts).
(d)
Working spaces about occasionally
					 exposed live parts.
When switches, disconnectors, and fuses above 750
					 volts are ordinarily guarded by covers or enclosed in separate rooms, but are
					 occasionally operated without such protection, either by removal of the covers
					 or by entrance into the rooms, adequate working space shall be provided about
					 the live parts, unless effectively isolated by elevation as required by §
											39.106 (relating to isolating live
					 parts by elevation), so that the operator is not required to bring any part of
					 his body within the following horizontal distances:
Voltage of
								  parts
Distances (in feet)
750-7,500
1
7,500-30,000
2
30,000-50,000
3
50,000-70,000
4
70,000-100,000
5
Above 100,000
6
(e) The distances given in subsection (d) are
					 slightly greater than those required to be maintained by operators near parts
					 of the corresponding voltage. Reference should also be made to §§
											39.364 and
					 39.365 (relating to voltages
					 between 750 and 7,500; voltages above 7,500). This is for the purpose of
					 provid,ing against inadvertent movements of operators and to insure that
					 operators of unusual height or size may be protected by this
					 provision.
(f) Below 7,500 volts
					 the distance specified in this section may be reduced if the operator uses
					 suitable operating devices.
This section cited in 34 Pa. Code §
													39.143 (relating to isolation by
						  elevation); 34 Pa. Code §
													39.171 (relating to accessibility
						  and convenient attendance); 34 Pa. Code §
													39.177 (relating to guarding live
						  parts); and 34 Pa. Code §
													39.182 (relating to provisions for
						  disconnecting).