714 LAWS OF MARYLAND. [CH. 307

SEC. 95. In every such mine wherever the condition of
grade, weight to be moved, and distance of movement or any
of them render placing of mine cars liable to physically injure
the miners if they are required to place such cars by their own
exertions, the Bureau may by general regulation require that
such cars, by mechanical or animal power, be placed at such
point in the heading, room or other excavation where the
miners are at work as shall be convenient without being further
moved for loading.

SEC. 96. The Bureau shall regulate and may prescribe con-
ditions for the installation, maintenance and operation of in-
ternal combustion engines, at or within any such mine.

SEC. 97. The Bureau shall prescribe such regulations for
the installation, maintenance and operation of coal cutting
machinery, including periodic examinations thereof, adequate
guarding of dangerous moving parts, protection from electric
shock, and proper support of roof and warning of bystanders,
as may assure reasonable protection of persons who may be
endangered by such machinery.

CHAPTER XIV—Ventilation.

SEC. 98. The operator of every such mine, whether oper-
ated by shaft, slope or drift, shall provide and hereafter main-
tain ample means of ventilation by the circulation of air
through the main and cross-entries, rooms and all other work-
ing places of such mine, to an extent that will dilute, carry
off and render harmless all noxious or dangerous gases, afford-
ing in non-gaseous mines not less than one hundred cubic feet
of air circulation per minute for each, person employed therein,
and three hundred cubic feet of air circulation per minute
for each animal employed therein; and in gaseous mines af-
fording not less than one hundred and fifty cubic feet of air
circulation per minute for each person, and five hundred cubic
feet of air circulation per minute for each animal, employed
therein; and as much more in either case as the district mine
inspector may by special safety order require.

SEC. 99. The operator shall direct and see that such air
circulation, by means of passages of sufficient area, shaped
and located to minimize friction and assure equable distri-
bution, is conducted through the last cut-through to the face
of each room and entry in such mine. No room or entry
shall be turned in advance of the ventilating current or of