Abstract: A method of transporting liquefied breathing gases in underground mines includes providing a conduit system that extends within a mine shaft to a work space below ground where the conduit system includes an outlet positioned in the work space, delivering liquefied breathing gases through the conduit system, and vaporizing the liquefied breathing gases at the outlet of the conduit system.

Abstract: A change over station (COS) for persons in a hazardous environment includes a steel housing having only a single entrance door, a chamber, and an air lock portion. The COS includes a first elongate seat disposed in the chamber and a plurality of compressed air cylinders disposed in the seat. The COS includes plumbing connected to the air cylinders formed of gas lines and valves and an exhaust muffler including first, second and third air paths that provide air into the chamber. The third air path is door activated when the door is opened by a door activated switch. The COS includes a storage portion disposed in the housing having supplies, including water and SCSRs or SCBAs. A method for providing a protected environment to miners from a mine environment in a mine.

Abstract: Apparatus and method for providing breathable air to one or more safe havens in an underground mine from a source external to the mine utilizing a source of compressed, breathable air located outside of the underground mine.

Abstract: A multiple activity apparatus is disclosed for educational, therapeutic, or recreational use comprising three rectangular frame members joined at abutting ends in a triangular configuration having open triangular ends. The triangular configuration has a base and upwardly converging sides with a utility board mounted in each respective frame member. Each board has an exterior work surface so that a pair of upright work surfaces are selectively positionable for use at any one time. A method of utilizing visual teaching aids comprises the steps of assembling three utility panels each having a side surface useful as a teaching aid; disconnectably joining each of the three panels in juxtaposition forming at least two junctures between panels with the exterior surfaces positioned at an angle for use as teaching aids; and stacking the three boards generally flat forming an assembly for transport.

Abstract: Mine ventilation tubing system for use in a mine tunnel including a plurality of tubing sections having, in transverse cross section, three sides connected together by three radiused corners, one of the corners having a substantially larger radius than the other two corners. A mounting assembly mounts the tubing sections in the tunnel with the one corner having the larger radius located closely adjacent the intersection of one of the side walls with the ceiling of the tunnel. In its mounted position, a first of the tubing section sides is located closely adjacent the ceiling, and a second of the tubing section sides is located closely adjacent the side wall such that the tubing sections are positioned out of the way of equipment travelling or operating in the tunnel.

Abstract: A self-propelled continuous mining machine which includes a mobile frame assembly having a material dislodging device, and a conveying system. A dust collecting system is positioned on the mobile frame assembly for inducing a flow of air through a duct system. As material is dislodged from a mine face, the dust collecting system draws airborne dust created by the dislodging device through the duct system and into the collecting system mounted on the mobile frame assembly. The duct system has two sets of vertical walls each connected to and spaced by a horizontal wall with one set of vertical walls fitting channel-like into the other set of vertical walls. The duct assembly has a gasket, seal or other means of preventing airborne dust from escaping through the two sets of vertical walls. The duct assembly is expandable to increase the capacity of the duct system.