Abstract: A mine safety system is provided for preventing coal dust explosions in an underground coal mine. The system comprises a reservoir, for storing an inerting agent; a compressor, for providing compressed air; and a mixer, coupled to the reservoir and the compressor, for mixing the inerting agent and compressed air and providing the mixture to the underground coal mine. The reservoir is located outside of the coal mine.

Abstract: A mine scoop machine having a steerable wheeled body provided with a material scoop having a load ejection blade mounted thereon for movement longitudinally of said body between a load position and a load ejection position adjacent an open front end of the scoop, operator controlled power means for moving the ejection blade selectively between the two positions for loading and unloading the scoop, a mine dusting unit mounted on the body rearwardly of the load position of the ejection blade, wherein the dusting unit comprises a dust hopper having a ground rock material feed inlet port and a rock dust outlet port, an air jet means on the unit for fluidizing the ground rock material and ejecting the resulting rock dust out into a mine shaft.

Abstract: Rock dust is applied to a mine wall for mine fire suppression in combination with a chemical foam, by generating the foam from air and a foamable liquid in a mixing chamber, and delivering the foam through one flexible conduit and a suspension of rock dust in water through another flexible conduit to a combiner, and causing the combined foam, rock dust and water to pass through a flexible hose to a delivery nozzle from which it is applied to a mine wall.

Abstract: A plurality of upstanding bracket assemblies, pipe assemblies, and fasteners are assembled into a plurality of modular fire suppression stations for use in the fire suppression system for a conveyor in an underground mine. Each station includes an upstanding bracket assembly, a fastener, a pipe assembly, and at least one sprinkler head. The fastener attaches the bracket assembly to the conveyor. The pipe assembly is supported by the bracket assembly. The pipe assembly receives water under pressure and directs the water to the sprinkler head. The sprinkler head directs the water onto the conveyor.

Abstract: A method of locating and controlling subsurface coal fires is provided that includes mapping a subsurface coal bed fire using a magnetometer, where the mapping includes locating a combustion zone and an air inlet to the combustion zone of the coal bed fire, drilling an injection port from the earth surface to a previously burned zone of the combustion zone, where the injection port is disposed between the air inlet and the combustion zone, inserting a tube in the injection port, where the tube has an exterior tube seal disposed around the tube, and the exterior tube seal isolates the earth surface from the combustion zone along an exterior of the tube. The method further includes injecting an inert gas through the tube to the combustion zone, where the inert gas controls the combustion zone of the coal bed fire.

Abstract: A rock dust blower and method draws rock dust from a portable supply of rock dust, in response to a flow of pressurized air, and entrains the drawn rock dust in a stream of the air for direction to selected surfaces of a coal mine. The supply is contained in a substantially vertical column and rock dust is drawn from the column along a peripheral edge of the column located adjacent the lower end of the column to thereby militate against cavitation of the rock dust adjacent the center of the column as rock dust is drawn from the supply. A vibrator mechanism can be employed to transmit vibration to the supply and thereby facilitate an even distribution of rock dust in the supply and a smooth and continuous flow of rock dust as rock dust is drawn from the supply.

Abstract: Rock dust is applied to a mine wall for mine fire suppression in combination with a chemical foam, by generating the foam from air and a foamable liquid in a mixing chamber, and delivering the foam through one flexible conduit and air-entrained rock dust through another flexible conduit to a portable assembly composed of a Y-joint and a delivery nozzle for combining the foam and rock dust and applying the combination directly to a mine wall.

Abstract: Foams and methods of using foams for fighting fires in confined areas (i.e., mine shafts) are provided. In one embodiment, a foam for extinguishing a fire is provided. The foam includes a surfactant; a non-flammable liquid; and an inert gas having a density substantially less than air. Preferably, the density of the foam is substantially less than the density of air. The light foam will allow a basic form of directional control of the foam because the light foam will float towards the ceiling of a cavern or mine shaft. This offers fire fighters several options in extinguishing an underground fire.

Abstract: A method and apparatus for controlling and extinguishing subterranean coal fires. Suitable detection and measuring devices are initially used to determine the extent of the fire and develop a plan of extinguishment. Flow control devices are added to all the mine's access points in order to control gas flow into and/or out of the mine. In addition, new access points may be added. Gaseous carbon dioxide is pumped into the mine until a positive pressure is developed (with respect to atmospheric pressure. Pressurized and liquefied carbon dioxide is directed into the area of the combustion face. The liquid carbon dioxide blankets the combustion area with a gas which will not support combustion and absorbs a tremendous amount of heat from the burning coal.

Abstract: A quick connect system for the assembly of underground mining dust and fire suppression systems can eliminate the need for threading pipe with couplings during the installation, reducing installation times approximately 75%. The quick connect system results in the quick and easy coupling and positioning of sprays along the water line. The quick connect system typically uses galvanized, brass and stainless steel components to reduce the need for replacement and to provide for quick adjustment of fittings with sprays using pliers. The system is simple to maintain and reduces high installation and maintenance labor costs. The system uses male and female ported fittings and horseshoe pins. Pendant style or deluge style sprays can be used in the system and can be pre-installed prior to delivery and installation of the system.

Abstract: A method is disclosed for controlling a mine fire by delivering a water absorbent polymeric composition to a rock structure involved in a fire and infusing the polymeric composition into the rock structure. The polymeric composition may also be used to create a seal across a mine entry for controlling underground mine fires.

Abstract: The present invention is directed to pyrotechnic aerosol fire suppression compositions that burn rapidly, but coolly. The rapid burning of the compositions of the present invention produces a voluminous flame-suppressive aerosol that is useful in suppressing and/or extinguishing both small and large fires. The compositions of the invention contain at least one oxidizer and a fuel component comprising at least one organic acid salt, which combination produces a rapid burning composition that burns at low temperatures with little or no flame and have a low heat of combustion.

Abstract: The present invention is directed to pyrotechnic aerosol fire suppression compositions that burn rapidly, but coolly. The rapid burning of the compositions of the present invention produces a voluminous flame-suppressive aerosol that is useful in suppressing and/or extinguishing both small and large fires. The compositions of the invention contain at least one oxidizer and a fuel component comprising at least one organic acid salt, which combination produces a rapid burning composition that burns at low temperatures with little or no flame and have a low heat of combustion.

Abstract: The device of the present invention is located in a closed containment enclosure surrounding a storage bin and comprises a closed tank (28) positioned on the storage bin containing a liquid (26) and having a fireproof shield enclosing the tank and a liquid level control system for controlling the level of liquid in the tank with the tank (28) comprising at least one opening in communication with the closed container enclosure, and at least one internal chamber in direct communication with the storage bin via a flue pipe and at least one external chamber in direct communication with the containment enclosure via said at least one opening.

Abstract: A method is disclosed for controlling a mine fire by delivering a water-absorbent polymeric composition to a rock structure involved in a fire and infusing the polymeric composition into the rock structure. The polymeric composition may also be used to create a seal across a mine entry for controlling underground mine fires.

Abstract: The present invention is directed to pyrotechnic aerosol fire suppression compositions that burn rapidly, but coolly. The rapid burning of the compositions of the present invention produces a voluminous flame-suppressive aerosol that is useful in suppressing and/or extinguishing both small and large fires. The compositions of the invention contain at least one oxidizer and a fuel component comprising at least one organic acid salt, which combination produces a rapid burning composition that burns at low temperatures with little or no flame.

Abstract: A method for forming a barrier to seal off a remote chamber includes the steps of: forming a borehole that communicates between a first location and the remote chamber; inserting a conduit through the borehole to extend into the remote chamber; introducing a flowable material through the conduit to the remote chamber and dispensing the flowable material from the conduit to the desired location for the barrier, the flowable material upon being dispensed producing a substantially solid, self-sustaining composition; maintaining dispensing the flowable material to produce a sufficient quantity of the self-sustaining composition to form the barrier to seal the remote chamber, while ensuring that the composition does not block the borehole from communicating between the first location and the remote chamber; and thereafter removing the conduit to allow access to the borehole.

Abstract: The method of the invention comprises the steps of proportioning a foam concentrate into a non-flammable liquid to form a foam concentrate/liquid mixture and creating a flowing stream of the foam concentrate/liquid mixture. Nitrogen is introduced into the stream of the foam/liquid mixture to initiate the formation of a nitrogen expanded foam fire suppressant. In one embodiment the nitrogen is chilled below ambient temperature. The flowing stream carrying the initially nitrogen expanded foam is dispensed, which completes the full expansion of the nitrogen expanded foam fire suppressant, into the confined area involved in fire thereby to smother the fire and to substantially close off contact between combustible material involved in fire and the ambient atmosphere substantially reducing the danger of explosion or flash fires.

Abstract: The method of the invention comprises the steps of proportioning a foam concentrate into a non-flammable liquid to form a foam concentrate/liquid mixture and creating a flowing stream of the foam concentrate/liquid mixture. Nitrogen is introduced to the stream of the foam/liquid mixture to initiate the formation of a nitrogen expanded foam fire suppressant. The flowing stream carrying the initially nitrogen expanded foam is dispensed, which completes the full expansion of the nitrogen expanded foam fire suppressant, into the confined area involved in fire thereby to smother the fire and to substantially close off contact between combustible material involved in fire and the ambient atmosphere substantially reducing the danger of explosion or flash fires. The apparatus of the invention is adapted for expanding and dispensing foam and comprises a housing defining an interior through which extend a discharge line.

Abstract: A canister fire extinguishing assembly includes a device that is adapted for removably coupling to a fire extinguisher. The device includes a container that has a bottom wall and a peripheral wall that is attached to and extends upwardly from the bottom wall. The peripheral wall has an upper edge. A mounting is attached to an outer surface of the peripheral wall for removably mounting the fire extinguisher to the container. A valve actuating assembly is removably coupled to the extinguisher. The valve actuating assembly is adapted for actuating a valve of the fire extinguisher and for directing pressurized fire extinguishing composition therein into the container when smoke is detected within the container or a temperature of greater than 50° C. is detected.

Abstract: A fire protection apparatus includes a plurality of bladders that are substantially filled with a non-flammable liquid via a manifold that is coupled to a source of non-flammable liquid and includes one or more nozzles that discharge the non-flammable liquid into each of the plurality of bladders. In one specific embodiment, the apparatus is initially in a substantially collapsed state at or near a ceiling. When fire or smoke is detected, the non-flammable liquid flows into the manifold. As the plurality of bladders begin to fill with non-flammable liquid, the weight of the filling bladders causes the fire protection apparatus to deploy, spanning from ceiling to floor. The bladders may include one or more discharge orifices that allow the non-flammable liquid to flow out of the bladder and down the exterior of the bladder once the bladder is filled to the level of its discharge orifices.

Abstract: A method and apparatus are provided for pneumatically controlling the operation of a water cannon such that the need for electrically power in the immediate vicinity of the water cannon is substantially avoided.

Abstract: A fire protection apparatus includes a plurality of bladders that are substantially filled with a non-flammable liquid via a manifold that is coupled to a source of non-flammable liquid and includes one or more nozzles that discharge the non-flammable liquid into each of the plurality of bladders. In one specific embodiment, the apparatus is initially in a substantially collapsed state at or near a ceiling. When fire or smoke is detected, the non-flammable liquid flows into the manifold. As the plurality of bladders begin to fill with non-flammable liquid, the weight of the filling bladders causes the fire protection apparatus to deploy, spanning from ceiling to floor. The bladders may include one or more discharge orifices that allow the non-flammable liquid to flow out of the bladder and down the exterior of the bladder once the bladder is filled to the level of its discharge orifices.

Abstract: The method of the invention comprises the steps of proportioning a foam concentrate into a non-flammable liquid to form a foam concentrate/liquid mixture and creating a flowing stream of the foam concentrate/liquid mixture. Nitrogen is introduced to the stream of the foam/liquid mixture to initiate the formation of a nitrogen expanded foam fire suppressant. The flowing stream carrying the initially nitrogen expanded foam is dispensed, which completes the full expansion of the nitrogen expanded foam fire suppressant, into the confined area involved in fire thereby to smother the fire and to substantially close off contact between combustible material involved in fire and the ambient atmosphere substantially reducing the danger of explosion or flash fires. The apparatus of the invention is adapted for expanding and dispensing foam and comprises a housing defining an interior through which extend a discharge line.

Abstract: The present invention provides an apparatus and method for the protection of off-road vehicles, such as ladle carriers, pot carriers, slag carriers and front end loaders which are used in high heat or flammable environments. The present invention prevents and/or limits damage from radiant heat, provides for the extinguishment of fires, provides a level of protection to the vehicle operator, and provides for the operator's escape from the vehicle at the onset of a fire or high heat incident. The apparatus and method of this invention implements the use of a liquid surfactant based wetting agent. The wetting agent is formulated to prevent radiant and ambient heat damage to the vehicle from radiant heat, flame and splashing of molten material on the vehicle. The wetting agent can be made to be environmentally safe. The present invention provides an increased level of safety to the operator, should the operator be required to escape from the vehicle in the event of a fire or high heat incident.

Abstract: A total flood fire suppression system is provided for transportation tunnels and other human-occupied environments, which employs a selective gas delivery method for supplying a breathable fire-extinguishing agent to a location closest to a fire site. The agent is produced from ambient air at site and stored in high-pressure containers communicating with an addressed gas delivery hose installed throughout a tunnel. When fire is detected, the agent is released from storage containers into the gas delivery hose that simultaneously becomes penetrated or broken in a location next to the fire site, allowing releasing the agent there and extinguishing the fire by totally flooding the affected portion of a tunnel. Additionally, the direction of the agent flow can be controlled by air blocks or inflatable tunnel plugs that, via a signal from a central control station, can inflate and block a tunnel tube in order to redirect the agent flow into the opposite to a block direction.

Abstract: A method for suppressing dissemination of dust from a pile of dust-producing bulk material, such as a pile of petroleum coke. The pile has a surface. The method comprises placing a sprayer apparatus on the pile, and discharging a liquid from the sprayer in a manner to distribute the liquid to at least an area of the surface of the pile.

Abstract: The present invention provides an apparatus and method for the protection of off-road vehicles, such as ladle carriers, pot carriers, slag carriers and front end loaders which are used in high heat or flammable environments. The present invention prevents and/or limits damage from radiant heat, provides for the extinguishment of fires, provides a level of protection to the vehicle operator, and provides for the operator's escape from the vehicle at the onset of a fire or high heat incident. The apparatus and method of this invention implements the use of a liquid surfactant based wetting agent. The wetting agent is formulated to prevent radiant and ambient heat damage to the vehicle from radiant heat, flame and splashing of molten material on the vehicle. The wetting agent can be made to be environmentally safe. The present invention provides an increased level of safety to the operator, should the operator be required to escape from the vehicle in the event of a fire or high heat incident.

Abstract: The invention relates to a fire fighting apparatus comprising a plurality of spray heads (5a′ to 5e′), a tube system (2′, 3a′, 3e′) for leading extinguishing medium from an extinguishing medium source (2′) having a volume for extinguishing medium to the spray heads, at least one drive gas source for driving extinguishing medium at a high pressure via the tube system to the spray heads, and release means for activating at least one of the spray heads.

Abstract: A fire extinguishing device for extinguishing a fire from a stationary fire extinguisher. The fire extinguishing device includes a housing having a top wall. A peripheral wall is integrally coupled to and extending downwardly away from the top wall such that the housing has an open bottom side. A canister for disbursing a fire retardant material is securely coupled to an inner surface of the top wall such that a valve mechanically coupled to the canister is directed towards the open bottom side. The canister contains a fire retardant material in a respectively pressurized environment. Control circuitry for actuating the valve is securely coupled to an inner surface of the peripheral wall and is operationally coupled to the valve. A sensor for sensing relatively high heat is electronically coupled to the control circuitry. The sensor is securely attached to the peripheral wall. A plurality of fastening members removably fastens the bottom wall to a ceiling wall.

Abstract: An assembled length of water pipe sections having a nozzle pipe section at an inby end is moved from a crosscut of a mine into a mine entry to stop the advance of a fire in the entry without requiring firefighters to be positioned in the fire entry. The nozzle pipe section is moved across the entry to a position adjacent to an opposite entry sidewall. The nozzle pipe section is connected at an outby end in the crosscut by assembled sections of extension water pipes to a water feedline. Water under pressure is supplied through the extension pipes to the nozzle pipe section and discharged from the nozzles to generate a series of intersecting sprays directed at selected angles in a range between about 0.degree. to 90.degree. in the entry, forming a water curtain the complete height and width of the entry.

Abstract: A support beam for a storage rack has a tubular profile, which defines a ledge opening upwardly and inwardly, and which defines a generally flat, indicia-receiving surface facing outwardly and either downwardly or upwardly at an angle from about 20.degree. to about 70.degree. relative to a vertical plane. Alternatively, the tubular profile may define two such surfaces defining an obtuse angle relative to each other, namely an upper surface at an angle from about 20.degree. to about 45.degree. relative thereto and a lower surface at an angle from about 45.degree. to about 70.degree. relative thereto, or a generally arcuate, indicia-receiving surface having a suitable measurement. The indicia-receiving surface enables a person who is standing, or who is sitting on a lift truck, to have a generally perpendicular line of sight to such surface. The support beam may also be used in combination with a properly positioned fire extinguishing device to extinguish a fire in a supported load.

Abstract: The seal is a lightweight, inflatable, bag which may be inflated by a portable air generator and is used to seal a burning mine passage. A collapsible tube-like aperture extends through the seal and allows passage of high expansion foam through the seal in a feed tube. The foam fills the passageway and extinguishes the fire. In other embodiments, the feed tubes incorporate means to prevent collapse of the aperture. In these embodiments a shroud connects the feed tube to a foam generator. This seal allows creation of a high expansion foam fire fighting barrier even in upward sloping passages.

Abstract: A support beam for a storage rack has a tubular profile, which defines a ledge opening upwardly and inwardly, and which defines a generally flat, indicia-receiving surface facing outwardly and either downwardly or upwardly at an angle from about 20.degree. to about 70.degree. relative to a vertical plane. Alternatively, the tubular profile may define two such surfaces defining an obtuse angle relative to each other, namely an upper surface at an angle from about 20.degree. to about 45.degree. relative thereto and a lower surface at an angle from about 45.degree. to about 70.degree. relative thereto, or a generally arcuate, indicia-receiving surface having a suitable measurement. The indicia-receiving surface enables a person who is standing, or who is sitting on a lift truck, to have a generally perpendicular line of sight to such surface. The support beam may also be used in combination with a properly positioned fire extinguishing device to extinguish a fire in a supported load.

Abstract: A fire barrier apparatus includes a wall separating two adjacent spaces, extending in a predetermined plane and formed from a fire resistant material. The wall has an opening. The apparatus further includes a conveyor defining a conveyor path which extends through the opening. The conveyor has at least one conveyor element within the predetermined plane. A shutter is included within the range of the opening. The shutter is composed of fire resistant material and is movable towards the conveyor element and away from it between an open position where the opening is free and a closed position where the opening is shut off. At least part of the shutter is included in an encasing arrangement for encasing the conveyor element in the closed position of the shutter. Several embodiments are described.

Abstract: A cryogenic slurry comprising a mixture of solid carbon dioxide particles suspended in liquid nitrogen is provided which is useful in extinguishing underground fires.

Abstract: A door includes an apparatus for reducing smoke associated therewith. The door is particularly advantageous in reducing smoke in a fire to thereby allow a firefighter or a victim trapped in a fire to readily indentify an exit. The door includes a nozzle or plurality of nozzles mounted upon the door, with a liquid source connected to the nozzle. Preferably, the door additionally includes a supply of pressurized water therein, with a surface active agent in an amount of 0.

Abstract: An expandable barrier for isolating a mine entry or similar open area is disclosed wherein the expandable barrier includes an expandable hollow curtain or bag housed within a horizontal brace member connected to the roof of an entry, the expandable hollow curtain being connected to vertical brace members adjacent to the walls of the mine entry. The expandable bag fills with a material capable of expanding the bag, such as a foam-like material, and expansion of the bag causes the bag to descend downwardly from the first horizontal brace member. The bag fills with distensible material in response to a stimulus detected by a monitor associated with the containers which contain the distensible material. A closeable opening or flap is disposed in the bag to allow passage of people or equipment therethrough. The expandable barrier may also be oriented in a horizontal position for use in vertical shafts.

Abstract: A fire suppression water spray array for an underground mining machine includes an accumulator, and a normally open electrically operated valve interconnected in the machine hydraulic control system for operating a hydraulically operated water spray control valve to initiate the water spray in the event of interruption of electrical power to the machine.

Abstract: An explosion suppression system and triggering apparatus therefor are provided for quenching gas and dust explosions. An electrically actuated suppression mechanism which dispenses an extinguishing agent into the path ahead of the propagating flame is actuated by a triggering device which is light powered. This triggering device is located upstream of the propagating flame and converts light from the flame to an electrical actuation signal. A pressure arming device electrically connects the triggering device to the suppression device only when the explosion is sensed by a further characteristic thereof beside the flame such as the pioneer pressure wave. The light powered triggering device includes a solar panel which is disposed in the path of the explosion and oriented between horizontally downward and vertical. Testing mechanisms are also preferably provided to test the operation of the solar panel and detonator as well as the pressure arming mechanism.

Abstract: The present invention relates to methods and apparatus for dispersing rock dust within a mine tunnel. The present invention is particularly useful for rock dusting coal mines. A quantity of rock dust is dispersed evenly over the conveyor system which runs through the area of the mine which requires dusting. The apparatus of the present invention comprises a wheeled vehicle having a diesel engine which drives the vehicle. In addition, the diesel engine drives a blower or fan. The vehicle of the present invention is adapted to run along the conveyor system within the mine. As a result, the vehicle runs over the rock dust which is dispersed on the conveyor belt. As the vehicle passes over the rock dust the fan which is associated with the vehicle blows into the rock dust causing the rock dust to disperse from the conveyor belt and to coat the associated interior tunnel.

Abstract: A method and formulation are provided which are effective for fighting coal fueled fires. The composition puts out the fire, penetrates the burning coal, disperses fire gases, and does not generate any gases that are toxic to humans. The basic formulation comprises a linear alkylbenzolyate sulfonate, non-ionic detergent and lauric superamide detergent mixture comprising about 50% by volume of the formulation, vitamin B-6 in the amount of about 0.5-3% by weight of the detergent mixture, bicarbonate of soda in the amount of about 3-18% by weight of the detergent mixture, red vegetable color in the amount of about 0.25-0.75% by weight of the detergent mixture, eucalyptus oil (if present) in the amount of about 1-2% by weight of the detergent mixture, and water comprising about 37-47% percent by volume of the total formulation.

Abstract: A series of specialty formulations of foaming mud cement are injected into an underground cavity containing an active coal fire. The fire is smothered and terminated with a blanket of foaming mud cement that sets into a cellular concrete. The lower section of the backfill involves a formulation of foaming mud cement containing materials conducive to heat transfer, thus forming a heat sink for dispersion of elevated temperature associated with the fire. The backfill continues to complete cavity fill using a formulation of foaming mud cement wherein the aggregate is composed of hazardous waste materials that are permanently stored within the cellular concrete.

Abstract: A foam generating apparatus includes a manifold defined by a rectangular metal block, into which a liquid and surfactant is introduced under very high pressure via a first longitudinally extending passage, and air is introduced via a second longitudinally extending passage parallel to the first passage. The liquid passes through restricted orifices into the narrow ends of a plurality of venturi outlet passages, which are perpendicular to the liquid inlet passage. The velocity of the liquid/surfactant mixture exiting the restricted orifices is maintained sufficiently high to cause flashing to take place to initiate foam generation. Air is injected into the venturi through small diameter ports extending from the second inlet passage to the venturi. The foam and liquid/gas mixture is discharged from the venturis through fittings which may contain vaned inserts for promoting turbulence and thus foaming. Foam production continues in the foam carrying lines downstream of the discharge bushings.

Abstract: An assembly installable at an underground mine site for storing breathing apparatuses and for facilitating access to and application of such apparatuses comprises a matrix of storage receptacles closable on a common side by respective spring-loaded hinged doors. An actuating mechanism is provided on an assembly frame for simultaneously releasing a multiplicity of latches locking the doors closed, the actuating mechanism being coupled to a valve for opening the same to permit the passage of air from a pressure source to a perforated tube mounted under a cylindrical roof on top of the compartment matrix. The roof has an opening for guiding a stream of air into a space in front of the storage assembly, thereby increasing the time available for a successful application of the breathing devices in a disaster involving the depletion of the atmospheric oxygen supply or the release of toxic fumes into the work area.

Abstract: A passive explosion barrier is provided for use in mining operations in suppressing mine explosions. The barrier basically comprises a receptacle or tub which contains an explosion suppressing substance, such as water, and is mounted on a frame adjacent to the roof of the mine. The tub includes a pair of integral support lips at the front and rear edges thereof which are beveled at the sides and which constitute the sole support for the tub. In operation, wind from an explosion will cause the lip disposed toward the explosion to distort and curve inwards and disengage from the frame so that the tub falls, pivoting about the other lip. In an alternative embodiment, the sides of the tub are more flexible than the lips of the tub, and distortion of the sides in response to wind forces causes disengagement of the lip facing the explosion.

Abstract: A fire-retarding polyurethane foam is applied to the interior surfaces of a mine such as mine shafts, entries and tunnels. The coating is applied by spraying a mixture of foam-forming ingredients including a hydrophilic polyoxyalkylene urethane prepolymer and a large amount of an aqueous slurry containing a phosphorous compound, alumina trihydrate and a char-forming material such as starch or wood cellulose. The foam coating acts as a protective sealant, and it can also be applied on other surfaces where insulation and fire retardancy are desired.

Abstract: Large amounts of low boiling liquefied gases are evaporated by heat transfer in a cylindrical combustion chamber without a convection component and a passage for the gas to be evaporated surrounds the combustion chamber so that the liquefied gas is exposed to a burner flame upon entry into the passage.

Abstract: A combustion chamber of an installation before its narrow section is made as two concentric tubes with a common vertical wall portion, featuring passages for supply of fuel and air into an annular space between the tubes. This space is sealed off at the outlet and divided by longitudinal partitions into two-way ducts with openings in the inner tube at the bottom. Relatively short partitions are preferably mounted along a helical line normal to tube surfaces to reduce the fuel-air flow resistance, resulting in higher efficiency of the installation.

Abstract: A method of treating barren earthen areas for inhibiting air and sun spoilation is disclosed, the method comprising forming an aqueous slurry of calcium sulfate hemihydrate with a small amount of defoamer using a quantity of water about 25-56% above normal consistency, the hemihydrate particles having a surface area of about 4,000-16,000 square centimeters per gram; and spraying the slurry onto the barren area to form a set, substantially air-impermeable covering to the barren area that will substantially exclude outside air from the area. The method is particularly applicable to controlling burning coal spoils and inhibiting spontaneous combustion of coal refuse banks.