34 Pa. Code Ch. 39 — Safety Standards—General

GENERAL PROVISIONS § 39.1. Definition of ‘‘establishment.’’ When used in this subchapter, the work ‘‘establishment’’ shall mean any place within this Commonwealth where work is done for compensation, to whomever payable, supervision over which is given by statute to the Departmen…

PROTECTIVE ARRANGEMENTS OF EQUIPMENT § 39.101. General requirement. Electrical supply equipment shall be of such construction and installed and maintained, so as to reduce the life hazard as far as practicable.

§ 39.102. Inspections. (a) Electrical supply equipment shall comply with this Subchapter when placed in service, and shall thereafter be periodically cleaned and inspected. Defective equipment shall be put in good order or permanently disconnected. Defective wiring, when hazardou…

§ 39.103. Protective grounding. (a) Grounding method. Lightning arresters, grounding, and all grounding of circuits, equipment or wire runways, intended to be a permanent and effective protective measure, shall be made in accordance with methods specified in § § 39.61—39.70 (rela…

§ 39.104. Working space about electrical equipment. (a) Adequate working space with secure footing shall be maintained about electrical supply equipment which requires adjustment or examination during operation. (b) Working spaces about exposed live parts over 300 volts to ground…

§ 39.105. Guarding live parts. (a) Protection shall be provided for persons near otherwise exposed ungrounded current-carrying parts of electrical supply equipment such as bus bars and other conductors on the terminals of generators and motors, operating at over 300 volts to grou…

§ 39.106. Isolating live parts by elevation. Current-carrying parts need not be guarded if they are maintained at the following distances above the floors which may be occupied by persons: Voltage of ConductorsElevation (in feet) 300—750 7 750—2,500 7 2,500—7,500 8 7,500—30,000 9…

§ 39.107. Identification. (a) Electrical supply equipment shall be suitably identified when necessary for safety. The identification may be by position, color, number, name, plate, label, design or other means. (b) The voltage and intended use shall be shown when important.

REQUIREMENTS § 39.11. Removal and replacement of guards. Under section 6 of act of May 18, 1937 (P. L. 654, No. 174) (43 P. S. § 25-6), no person shall remove or make ineffective any safeguard, safety appliance, or device attached to machinery or guarding a hazardous condition ex…

ROTATING EQUIPMENT § 39.111. Speed control and stopping devices. (a) Prime movers driving generating equipment shall be provided with automatic speed-limiting devices, in addition to their governors, if necessary, as with some types of steam turbines where harmful overspeed may o…

§ 39.112. Protecting shaft ends, pulleys, belts, and other moving parts. Pulleys, belts, and shaft ends, projecting through bearings, revolving armatures, revolving fields, and other moving parts shall either be entirely enclosed in suitable casings or otherwise adequately guarde…

§ 39.113. Guards for live parts. (a) Suitable insulating mats or platforms of substantial construction providing good footing shall be placed on floors and, if necessary, on frames of machines having exposed live parts above 300 volts to ground, so that no operator may readily to…

§ 39.114. Hazardous locations. (a) If explosives, inflammable gas, or inflammable flyings normally exist in dangerous quantities, the parts at which sparking or arcing are liable to occur shall be enclosed so as to reduce the hazard as far as practicable. This enclosure shall be …

§ 39.115. Grounding noncurrent-carrying parts. (a) Exposed noncurrent-carrying metal parts of rotating electrical supply equipment shall be permanently grounded in accordance with the requirements for grounding provided in § 39.103 (relating to protective grounding). (b) If machi…

§ 39.116. Deteriorating agencies. (a) Suitable guards or enclosures shall be provided to protect exposed current-carrying parts, insulation of leads, balancing coils or other electrical devices belonging to motors and generating equipment if installed directly under equipment or …

§ 39.12. Operating rules. (a) The hand dressing of belts while they are driving machinery is prohibited. (b) Belts shall not be placed on pulleys or taken off pulleys by direct hand method while the pulleys are in motion. (c) The cleaning and oiling of machinery while in motion i…

STORAGE BATTERIES § 39.121. Applicability. The provisions of § § 39.121—39.127 (relating to storage batteries), except for § 39.125 (relating to guarding live parts in battery room), shall apply only to storage batteries exceeding 50 kilowatt hours capacity at the 8 hour rate of …

§ 39.122. Isolation. Storage batteries shall be made inaccessible to other than properly qualified persons by being placed in a separate room or enclosure. Cross References This section cited in 34 Pa. Code § 39.85 (relating to general requirements); 34 Pa. Code § 39.121 (relatin…

§ 39.123. Ventilation. Rooms or enclosures containing storage batteries shall be ventilated so as to remove acid spray and prevent dangerous accumulation of inflammable gas. Communication of drafts to other rooms shall be prevented. Cross References This section cited in 34 Pa. C…

§ 39.124. Suitable supports and floors. The cells of storage batteries shall be supported by suitable insulators, except small cells of insulating material. Suitable drainage or other means shall be provided beneath cells to prevent the accumulation of electrolyte in case of leak…

§ 39.125. Guarding live parts in battery room. (a) The arrangement of cells and connections shall be such that no two current-carrying parts between which a voltage exceeding 150 exists, shall be closer than three feet, if the parts are so exposed that persons are liable to make …

§ 39.126. Illumination. Storage battery rooms shall be lighted, if practicable, from outside lamps. If lamps are inside, only incandescent electric lamps in keyless porcelain or composition sockets, controlled from points not exposed to battery vapor, shall be used. Cross Referen…

§ 39.127. Acid-resisting coverings. Conductors in battery rooms, if of such material or so located as to be liable to corrosion, shall have suitable protective coverings or coatings, unless the ventilation is such as to render this unnecessary. Cross References This section cited…

TRANSFORMERS, REACTANCES, INDUCTION REGULATORS,BALANCE COILS AND SIMILAR EQUIPMENT § 39.131. Current transformers secondary circuits. (a) Secondary circuits of current transformers including constant current and instrument transformers, except those supplying relays only, or thos…

§ 39.132. Grounding low voltage circuits of instrument transformers. The low voltage circuit of instrument transformers shall be permanently grounded unless the circuits are installed, guarded, and plainly identified as required for the high voltage circuits of the transformers. …

§ 39.133. Grounding transformer cases. (a) The metal case or exposed frame of each transformer, reactance, and similar equipment, which is located where dampness or inflammable gas normally exists, or which is connected to a circuit operating at over 150 volts to ground, shall be…

§ 39.134. Transformers. Transformers shall be installed according to any one of the following methods: (1) On poles or, when permitted by local authority, on walls of buildings, in which case they shall comply with overhead line rules. (2) In rooms in which other equipment is ins…

WIRING AND PROTECTION AND CONTROL EQUIPMENT § 39.141. Electrical protection from conductors. (a) Conductors shall be suitable for the location, use, and voltage. Conductors shall be protected against excessive heating by the design of the system or by automatic cut-outs, unless g…

§ 39.142. Mechanical and thermal protection. (a) If exposed to mechanical injury, suitable casing, armor, or other means shall be employed to prevent injury or disturbances to conductors, their insulation, or supports. (b) If conductors with insulating coverings are closely group…

§ 39.143. Isolation by elevation. All conductors over 750 volts, and ungrounded bare conductors over 300 volts to ground shall be isolated by elevation as required by § 39.106 (relating to isolating live parts by elevation), unless guarded in accordance with § 39.144 (relating to…

§ 39.144. Guarding conductors. (a) Use of enclosed casings. If insulated conductors are enclosed, suitable permanently grounded metal conduit or grounded metal sheating shall be used; or in lieu thereof other ducts, runways, or compartments of tile, bitumenized fiber, concrete, o…

§ 39.145. Guarding in hazardous locations. (a) Conductors in locations where inflammable gas normally exists shall be in metal conduit or metal sheathed cable. Fittings and outlets of such conduit and cable shall be electrically and mechanically continuous with the conduit or met…

§ 39.146. Pendants and portables. (a) Pendant conductors shall not be installed if they may readily be moved so as to bring them in contact with live parts of electrical supply equipment. (b) Portable conductors shall be attached to fixed wiring only through separable attachment …

§ 39.147. Temporary wiring. Temporary wiring which is not in compliance with this subchapter may be used when it is constantly under competent supervision or protected by suitable barrier guards and warning signs while it or neighboring wiring is alive and accessible to any perso…

§ 39.148. Taping ends and joints. Ends and joints of insulated conductors, unless otherwise adequately guarded, shall have equal insulating covering with other portions of the conductor.

FUSES AND OTHER CUT-OUTS, SWITCHES, AND CONTROLLERS § 39.151. Accessible and indicating. Switches, automatic cut-outs, starting rheostats and other control devices shall be readily accessible to authorized persons. They shall be arranged or marked so as to identify the equipment …

§ 39.152. Hazardous locations. In locations where explosives, inflammable gas, or inflammable flyings normally exist in dangerous quantities, all parts at which sparking or arcing are liable to occur shall, if practicable, be so inclosed as to prevent hazard. Reference should als…

§ 39.153. Required placement of switches. (a) Suitable switches or cut-outs which may be manually operated shall be inserted in all leads, except a grounded conductor, to generators, motors, transformers, other than instrument transformers, and outgoing supply circuits. (b) In mo…

§ 39.154. Switches or other grounding devices. Switches or other suitable means should be provided, where practicable, to facilitate short circuiting and grounding equipment or lines for which the operating rules require grounding to protect workmen. Cross References This section…

§ 39.155. Character of switches and disconnectors. (a) Capacity. Switches used as other than disconnectors shall be of suitable voltage and ampere rating for the circuit on which they are installed, and be marked with the current which they are able to safely interrupt. Disconnec…

§ 39.156. Cut-outs. (a) Circuit leads to motors, transformers, or station auxiliaries shall be protected by suitable automatic cut-outs, except as noted in § 39.141 (relating to electrical protection from conductors). (b) If two or more pieces of electrical supply equipment or su…

§ 39.157. Disconnecting of fusible cut-outs before handling. Fusible cut-outs in circuits operating at over 150 volts to ground shall be arranged in any one of the following ways: (1) Ungrounded current-carrying parts are not touched by persons refusing the cut-outs until the fus…

§ 39.158. Arcing or suddenly moving parts. (a) Fuses and circuit breakers shall, as far as possible, be so located and shielded that persons may not be burned by their operation. (b) Handles or levers of circuit breakers and similar parts which may move suddenly, in such a way th…

§ 39.159. Grounding noncurrent-carrying metal parts. (a) Exposed noncurrent-carrying metal parts of switch and fuse cases, levers, and other similar parts with live parts liable to leak, creating a hazard, shall be permanently grounded according to the provisions of § 39.103 (rel…

§ 39.160. Guarding live parts of switches and automatic cut-outs not installed on switchboards. (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 …

SWITCHBOARDS § 39.171. Accessibility and convenient attendance. Switchboards shall have switches so arranged that the points of control are readily accessible to the operator. Instruments, relays, and other devices requiring reading or adjustments shall be so placed that work may…

§ 39.172. Location and illumination. (a) Switchboards shall, if practicable, be so placed that the operator is not endangered by any live or moving parts of machinery or equipment located near the board. (b) Sufficient illumination shall be provided both for the front and rear of…

§ 39.173. Necessary equipment. Switchboards which control outgoing supply circuits shall, except in substations without regular attendance, be equipped with such instruments as are necessary to show operating conditions.

§ 39.174. Arrangement and identification. Connections, wiring and equipment of switchboards and panelboards shall be arranged in an orderly manner and switches and cut outs shall be plainly marked, labeled or arranged to afford ready means for identifying circuits or equipment su…

§ 39.175. Spacings and barriers against short circuit. (a) Switchboards shall have the number of bare parts at different potentials on any panel reduced to a minimum, and these parts shall be effectively separated. If voltage exceeds 750, such parts should be protected or separat…