45.1-161.225 - Ventilation controls. - Virginia Statutes

§ 45.1-161.225. Ventilation controls.

A. Ventilation shall be so arranged by means of air locks, overcasts, orundercasts that the passage of haulage trips or persons along the entrieswill not cause interruption of the air current. Air locks shall be ventilatedsufficiently to prevent accumulations of methane therein.

B. Air lock doors that are used in lieu of permanent stoppings or to controlventilation within an air course shall be (i) made of noncombustible materialor coated on all accessible surfaces with flame-retardant material having aflame spread index of 25 or less as tested under ASTM E 162-187 and (ii) ofsufficient strength to serve their intended purpose of maintaining separationand permitting travel between or within air courses or entries.

C. To provide easy access between the return, belt and intake escapewayentries, substantially constructed man-doors properly marked so as to bereadily detected shall be installed in at least every fifth crosscut in thestopping lines separating such entries.

D. Doors shall be kept closed except when miners or equipment is passingthrough the doorways. Motor crews and other miners who open doors shall seethat the doors are closed before leaving them.

E. Overcasts, undercasts, and regulators shall be well constructed ofincombustible material, such as masonry, concrete, concrete blocks, orprefabricated metal. They shall (i) be of sufficient strength to withstandpossible falls from the roof, (ii) be of ample area to pass the requiredquantity of air, and (iii) be kept clear of obstructions.

(Code 1950, § 45-60.4; 1954, c. 191; 1966, c. 594, § 45.1-60; 1993, c. 442;1994, c. 28; 1996, c. 774; 2005, c. 3.)