Drill holes large enough to constitute a hazard shall be covered or guarded. Fuel lines shall be equipped with valves capable of stopping the flow of fuel at the source and shall be located and maintained to minimize fire hazards. (a) If truck spotters are used, they shall be in the clear while trucks are backing into dumping position or dumping. 57.16002 Bins, hoppers, silos, tanks, and surge piles. Insulation means a dielectric substance offering a high resistance to the passage of current and to a disruptive discharge through the substance. 57.22307 Methane monitors (II-A mines). (d) Spills shall be cleaned up promptly with nonsparking equipment. Smoking shall be prohibited in all areas of a mine where exposure records are required to be kept in compliance with standard 57.5040. (b) Seals shall be of substantial construction. (a) The mine shall be nongassy and shall have multiple horizontal or inclined roadways from the surface large enough to accommodate vehicular traffic; (b) All roadways and other openings shall connect with another opening every 100 feet by a passage large enough to accommodate any vehicle in the mine or alternate routes shall provide equivalent escape capabilities; and. (2) Where uranium is not minedwhen radon daughter concentrations between 0.1 and 0.3 WL are found in an active working area, radon daughter concentration measurements representative of worker's breathing zone shall be determined at least every 3 months at random times until such time as the radon daughter concentrations in that area are below 0.1 WL, and annually thereafter. 552(a) and 1 CFR part 51. 57.19066 Maximum riders in a conveyance. (a) All mine main and booster fans installed and used to ventilate the active workings of the mine shall be operated continuously while persons are underground in the active workings. (c) ROPS labeling. [56 FR 46517, Sept. 12, 1991; 56 FR 52193, Oct. 18, 1991]. Upon abandonment of a mine, the owner or operator shall effectively close or fence off all surface openings down which persons could fall or through which persons could enter. (c) Where average gamma radiation measurements are in excess of 2.0 milliroentgens per hour in the working place, gamma radiation dosimeters shall be provided for all persons affected, and records of cumulative individual gamma radiation exposure shall be kept. (a) Cutting and drilling equipment used at a face or bench shall be approved by MSHA under the applicable requirements of 30 CFR parts 18 through 36. Before loading, blastholes shall be checked and, wherever possible, cleared of obstructions. (a) On the surface, no more than one day's supply of combustible materials shall be stored within 100 feet of mine openings or within 100 feet of fan installations used for underground ventilation. (a) Two independent brakes, each capable of holding the maximum load; (b) Direct communication between terminals; (c) Power drives with emergency power available in case of primary power failure; and. 291Testing and Marking Hydrants. 57.19061 Maximum hoisting speeds. 57.3200 Correction of hazardous conditions. Closed, nonconductive containers shall be used to carry explosives and detonators to and from blast sites. Fire resistance rating means the time, in minutes or hours, that an assembly of materials will retain its protective characteristics or structural integrity upon exposure to fire. The individual shall be currently trained and have the skills to perform patient assessment and artificial respiration; control bleeding; and treat shock, wounds, burns, and musculoskeletal injuries. 57.19091 Signaling instructions to hoist operator. During shift changes, the movement of underground trains carrying rock or material shall be limited to areas where the trains do not present a hazard to persons changing shifts.
