Ohio § 1567.17

§ 1567.17.

Where direct current is used underground in mines, the following rules shall govern: (A) In determining the voltage limit the difference in potential shall not exceed three

hundred twenty-five volts measured by a meter at the nearest switchboard except with

the written approval of the chief of the division of mineral resources management. (B) For the protection of circuits, a switch and circuit breaker shall be installed in

the ungrounded side of the circuit, but may be omitted from the return side.  Fuses may be substituted for circuit breakers transmitting twenty-five kilowatts

or less.  Each circuit leading in the underground workings of such mine shall be provided

with a suitable ammeter.  Additional switches shall be installed in the ungrounded side of all branch circuits. (C) One side of grounded circuits shall be very efficiently insulated from the earth. (D) All trolley and feed wires shall be placed on the opposite side of the track from

refuge holes or necks of room.  All lines except telephone, shot firing, and signal lines shall be on the same side

as the trolley lines. (E) All terminal ends of feed and trolley wires shall be guarded to prevent persons from

inadvertently coming in contact with them. (F) No locomotive shall be operated by means of a person holding and sliding upon, or

frequently making contact with, the positive wire with any device attached to the

cable as a substitute for a trolley, except to move a locomotive out of traffic because

of a broken trolley pole or fixtures attached thereto.  This does not prohibit the operation of a locomotive by means of a cable without

the use of the trolley, if the connection with and disconnection from the positive

wire is made when the locomotive is not in motion. (G) Inside the mine the trolley wire shall be installed parallel to the gauge line of

the rail and as far away as practical, and in no place closer than six inches from

the gauge line, except where written permission is given by the chief.  The trolley wire shall be securely supported on hangers efficiently insulated.  Such hangers shall be placed at intervals of not exceeding thirty feet and at less

intervals if it is necessary to prevent the sag between points of support exceeding

three inches.  Hangers installed after September 2, 1941, shall be of sufficient height to place

the trolley wire within six inches of the roof or cross timbers at the point of trolley

wire support, except where the trolley wire may be above the top of the normal seam

or draw slate taken with the seam or six feet six inches from the top of the rail. (H) In underground workings all feed wires shall be in places either above the trolley

wire on the same hangers, between trolley wire and rib, or on the rib as close to

the roof as practicable, and securely supported on hangers sufficiently insulated,

not more than fifty feet apart.  If feed wires are installed in entries that are not equipped with trolleys, they

are to be installed as close to the rib as practicable. (I) Recharging stations for battery locomotives located inside a mine shall be adequately

ventilated at all times.  All charging panels shall be equipped with automatic overload circuit breakers and

ammeters.  All refuse or movable material of an inflammable nature shall be kept out of such

stations. (J) All trolley and positive feed wires crossing places where persons or animals are

required to travel shall be safely guarded or protected from such persons or animals

coming in contact with such wires, except where such wires are above the top of normal

seam or draw slate taken with the seam, or six feet six inches from the top of the

rail. (K) No trolley wire shall be extended into or maintained in any room while being used

as a working place;  no trolley or feed wire shall be extended into any entry beyond

the outside corner of the last break-through, except in case of systems of mining

or equipment approved by the chief. (L) When necessary to carry bare wires down shafts or slopes used as traveling ways,

the wires shall be thoroughly protected so that persons cannot inadvertently come

in contact with them. (M) When positive machine feed wires are extended into rooms, they shall be placed not

nearer than four feet from the rail where the room is of sufficient width, and shall

only be connected to the positive wire on the entry while in actual use.  The wire used for making such connections shall be of sufficient length to reach

across the entry, and when the same is disconnected, it shall be removed from the

entry or be kept with the machine.  No electric wires shall be extended into any room unless a one hundred fifty foot

trailing cable will not reach the face of the room, and then not beyond the outside

corner of the last break-through, except in the case of systems of mining and equipment

approved by the chief.  Means shall be provided by which machine runners may readily install the machine

cable across the entry so as to render it free from ground, and so the cable will

not come in contact with persons or animals required to travel such entry. (N) Any track or rail that is used as a return circuit shall be properly bonded.  When metallic pipelines parallel a rail or track used for return, the pipe may be

bonded to the rail at both ends to avoid electrolysis, and if the pipeline is of unusual

length, intermediate bonds shall be installed.  No pipeline or any part thereof shall be used exclusively as the return.  In a section of a mine where electric detonators or electric squibs are used, metallic

pipeline rails and return lines in that section shall be bonded together. (O) All lighting circuits of a mine, whether underground or outside, shall be installed

in such a manner that they will not be a fire hazard or will not endanger persons

coming in contact therewith. No operator of a mine shall refuse or neglect to comply with this section.