1058 LAWS OF MARYLAND. [CH. 437

than 1. 0 per cent methane, as determined with a per-
missible flame safety lamp, by air analysis, or by other
recognized means of accurate detection, the ventilation
shall be improved.

(c) If the air immediately returning from a split con-
tains 1. 5 per cent methane, the employees shall be with-
drawn from the mine or portion of the mine affected, and
all power shall be cut off from said mine or portion of the
mine, until such dangerous condition has been corrected.

(d) At working faces and other places where methane
has accumulated and is likely to attain an explosive mix-
ture, blasting shall not be done and the men shall be re-
moved from such working faces or places until such con-
dition has been corrected.

(e) When the methane content of air in face operations
exceeds. 1 per cent at any point not less than 12 inches
from the roof, face, or rib, as determined by a permissible
methane detector, a permissible flame safety lamp, or by
chemical analysis, the men shall be removed from the af-
fected area until the condition has been corrected by im-
proving the ventilation.

104. Crosscuts and Stoppings (a) Crosscuts between
entries and rooms shall be made at intervals not to exceed
105 feet, provided, that the requirements of this Section
shall not apply to recovery work where the working faces
are ventilated by a perceptable movement of air than con-
tains not less than 19. 5 percent oxygen and not more than
0. 75 percent carbon dioxide.

Crosscuts between entries shall be closed, except the last
one in a pair or set of entries.

(b) Where necessary to obtain a movement of air to
the face of a room to clear the room of flammable or nox-
ious gases, crosscuts between rooms shall be closed, except
the one nearest the face.

(c) A crosscut shall be provided at or near the face of
each entry or room before the place is abandoned.

(d) Entries, rooms, or chutes shall not be turned off an
entry beyond the last crosscut. This does not apply to the
driving of such places to make a connection at the first
crosscut or similar passageway used as a main airway
in connection with an entry. It does apply to extending
such places beyond the airway before the main intake and
return passageways are connected.