                                 CODE OF VIRGINIA

 VENTILATION CONTROLS (§ 45.2-842)

A. Ventilation shall be so arranged by means of air locks, overcasts, or
undercasts that the passage of a haulage trip or person along the entries will
cause no interruption of the air current. Each air lock shall be ventilated
sufficiently to prevent an accumulation of methane therein.

B. Air lock doors that are used in lieu of permanent stoppings or to control
ventilation within an air course shall be (i) made of incombustible material or
coated on all accessible surfaces with flame-retardant material having a flame
spread index of 25 or less as tested under ASTM E162 and (ii) of sufficient
strength to serve their intended purpose of maintaining separation and
permitting travel between or within air courses or entries.

C. To provide easy access between the return, belt, and intake escapeway
entries, substantially constructed man-doors that are properly marked so as to
be readily detected shall be installed in at least every fifth crosscut in the
stopping line separating such entries.

D. Doors shall be kept closed except when a miner or piece of equipment is
passing through the doorway. Any motor crew or other miner who opens such doors
shall see that they are closed before leaving them.

E. Overcasts, undercasts, and regulators shall be well-constructed; of
incombustible material, such as masonry, concrete, concrete block, or
prefabricated metal; and (i) of sufficient strength to withstand possible falls
from the roof, (ii) of ample area to pass the required quantity of air, and
(iii) kept clear of obstructions.

HISTORY: Code 1950, § 45-60.4; 1954, c. 191; 1966, c. 594, § 45.1-60; 1993, c.
442; 1994, c. 28, § 45.1-161.225; 1996, c. 774; 2005, c. 3; 2021, Sp. Sess. I,
c. 387.