[Code of Federal Regulations]
[Title 30, Volume 1]
[Revised as of July 1, 2002]
From the U.S. Government Printing Office via GPO Access
[CITE: 30CFR18.48]

[Page 103-104]
 
                       TITLE 30--MINERAL RESOURCES
 
  CHAPTER I--MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR
 
PART 18--ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES--Table of Contents
 
             Subpart B--Construction and Design Requirements
 
Sec. 18.48  Circuit-interrupting devices.

    (a) Each machine shall be equipped with a circuit-interrupting 
device by means of which all power conductors can be deenergized at the 
machine. A manually operated controller will not be acceptable as a 
service switch.
    (b) When impracticable to mount the main-circuit-interrupting device 
on a machine, a remote enclosure will be acceptable. When contacts are 
used as a main-circuit-interrupting device, a means for opening the 
circuit shall be provided at the machine and at the remote contactors.
    (c) Separate two-pole switches shall be provided to deenergize power 
conductors for headlights or floodlights.

[[Page 104]]

    (d) Each handheld tool shall be provided with a two-pole switch of 
the ``dead-man-control'' type that must be held closed by hand and will 
open when hand pressure is released.
    (e) A machine designed to operate from both trolley wire and 
portable cable shall be provided with a transfer switch, or equivalent, 
which prevents energizing one from the other. Such a switch shall be 
designed to prevent electrical connection to the machine frame when the 
cable is energized.
    (f) Belt conveyors shall be equipped with control switches to 
automatically stop the driving motor in the event the belt is stopped, 
or abnormally slowed down.
    Note: Short transfer-type conveyors will be exempted from this 
requirement when attended.