STATISTICS AND INFORMATION. 2795

knowingly damage any signal or communication system, or knowingly,
give or cause to be given any wrong signal within or about such mine, or
deface or destroy any general or special rules or mining laws, or know-
ingly destroy, falsify or remove or conceal any record or report herein re-
quired to be made and kept, shall be guilty of a misdemeanor.

CHAPTER XVI—Electricity in Mines and Mining.
1922, ch. 307, sec. 109.

110. All electric systems employed in, at, or about any mine in this
State shall be installed, extended and/or operated subject to reasonable
regulation and supervision by the Bureau; Provided, That in making
and amending such regulations, due regard shall be paid to commercially
accepted and approved underwriters' regulations, and to electric regula-
tions recommended by the United States Bureau of Mines.

1922, ch. 307, sec. 110.

111. The various electric systems shall be classified by voltages as fol-
lows : All such systems wherein the maximum voltage cannot exceed 300
volts shall be known as " low voltage " systems. All such systems wherein
the voltage exceeds 300 volts but the maximum whereof cannot exceed
650 volts shall be known as " medium voltage " systems. All such sys-
tems wherein the voltage can exceed 650 volts shall be known as " high
voltage " systems.

1922, ch. 307, sec. 111.

112. Every six months the operator of every coal mine in which any
electric system exists shall make an " electric system map " of such mine,
which shall show by distinguishing colors and signs upon a good exact
reproduction of the map of such mine as hereinbefore required to be made,
as the same has been extended to date, such electric system, in such detail
as may be prescribed by the Bureau. Identical copies of such electric sys-
tem map shall be kept in the office of the foreman at such mine and filed
with the district mine inspector for his official use.

1922, ch. 307, sec. 112.

113. At every mine where electricity is used for power, there shall be
employed a competent mine electrician who shall have full charge of the
electric apparatus and system in and about such mine, but who shall be
subject to the authority of the official in charge of such mine.

1922, ch. 307, sec. 113.

114. All electric apparatus shall be of approved type, strongly de-
signed and constructed and of ample capacity for the purpose intended or
to which it may be put; all parts carrying electric current shall be effect-
ually insulated against the conditions of such intended service; and the
installation thereof shall be so protected that hazards to life and property
may be minimized.