Abstract: The present invention provides a flexible respirator filter having substantially coextensive front and back portions of filter material which are sealed to each other along their periphery, forming a sealed edge. A flexible plastic frame is contained within the front and back portions to form a plenum between the front and back portions of filter material. The frame has a peripheral edge which remains adjacent to the sealed edge of the filter material along substantially the entire length of the sealed edge to provide sufficient rigidity to prevent crushing while at the same time providing sufficient flexibility to fit under other personal protective equipment. A connector for attaching the filter to the respirator mask is formed integrally with the frame such that it protrudes through the back portion of the filter material. A plurality of recesses are also formed integrally with the frame to facilitate grasping the filter without crushing or damaging it.

Abstract: A gas sensor for the detection of gases comprises a housing and an active element disposed within the housing. The active element is surrounded by a porous insulating material having a bulk density no greater than 0.15 g/cc. Another gas sensor comprises an active element surrounded by a porous insulating material having a surface area no greater than approximately 200 m2/cc. Another gas sensor comprises a copper compound positioned so that gas contacts the copper compound before contacting the active element. Another gas sensor comprises an active element surrounded by a porous material having an average pore size of at least approximately 100 Å. Another gas sensor comprises a heating element surrounded by a porous material that supports a catalyst.

Abstract: The present invention provides a filter containing a filter material folded into a chrysanthemum shape. While such a filter can be made of an electret fiber nonwoven fabric or a fiberglass nonwoven fabric, preferably it is made of a polytetrafluoroethylene porous film that is extended lengthwise and widthwise such that the overall area is extended by more than fifty-fold.

Abstract: Radio interface apparatus in combination with a lapel mounted microphone and speaker and a radio and with or without a head-protective helmet, radio interface apparatus in combination with a lapel-mounted radio and with or without a head-protective helmet, and radio interface apparatus for being mounted to the nape device of a head-protective helmet.

Abstract: A synthetic route for forming lithium trisubstituted borohydride compounds comprises the step of reacting a processed lithium hydride reactant with a trisubstituted borane wherein the reaction is maintained for a period of time in a temperature range of approximately 15° C. to approximately 42° C. A method of synthesizing LiH comprises the step of reacting an alkyl lithium (for example, n-butyl lithium) with hydrogen in the presence of tetrahydrofuran. The reaction temperature is preferably maintained in the range of approximately −78° C. to approximately 25° C.

Abstract: A faceshield that is securable to a protective helmet or headband having an indexable pivot joint which utilizes an interference fit between an O-ring and radially spaced lug sets. The O-ring is compressed when the crests of the two sets of lugs are radially aligned. This interference holds the faceshield in a desired indexed position.

Abstract: A head-protective helmet comprising a geodesic dome. A further feature is the geodesic dome in combination with other elements providing a head-protective helmet.

Abstract: A small, portable electrochemical power cell, having an output voltage of over 4 V, and preferably over 5 V, includes an anode, a cathode having a fluorine compound and an electrolyte having an organic sulfur-containing compound to maintain ionic conductivity between the anode and the cathode. A method of fabricating such an electrochemical power cell includes the step adding an electrolyte having an organic, sulfur-containing compound to maintain electrical conductivity between the anode and the cathode. An electrochemical power cell having a lithium anode, a CoF3 cathode, an electrolyte to maintain ionic conductivity between the anode and the cathode and a cobalt complexing material within the electrolyte to complex cobalt ions is described.

Abstract: A method of increasing enantioselectivity in a reduction reaction of a prochiral substrate with a borane reagent including a borohydride species (for example, a borohydride stabilized borane-tetrahydrofuran complex) catalyzed by a chiral catalyst includes the step of maintaining the concentration of borohydride species in the borane reagent below approximately 0.005 M during the reduction of the prochiral substrate. A method of increasing enantioselectivity in a reduction reaction of a prochiral substrate with a borane reagent including a borohydride species that is catalyzed by a chiral catalyst includes the step of reducing the detrimental effect the borohydride species has on enantioselectivity by adding a Lewis acid. For example, the prochiral substrate can be a ketone and the chiral catalyst can be a chiral oxazaborolidine.

Abstract: A motion sensor having an electrically-conductive ball and at least a second ball to damp the motion of the electrically-conductive ball. Both balls are confined within a housing. A plurality of electrical contact elements are disposed within the housing. During movement, the electrically-conductive ball successively forms electrical connection with the electrical contact elements within the housing. The motion sensor also includes detection circuitry in electrical connection with the electrical contact elements to detect if the electrically-conducting ball is moving.

Abstract: A small, portable electrochemical power cell, having an output voltage of over 4 V, and preferably over 5 V, includes an anode, a cathode comprising a fluorine compound and an electrolyte to maintain ionic conductivity between the anode and the cathode. A method of fabricating such an electrochemical power cell includes the step of adding a fluorine compound to the cathode and/or to the electrolyte solvent.

Abstract: The present invention provides an electrochemical sensor for the detection of hydrogen chloride. In general, the electrochemical sensor comprises a housing having disposed therein a working electrode, a reference electrode and a counter electrode. The electrochemically active surface of the working electrode preferably comprises a gold film having a thickness of approximately 1000 to 3000 .ANG.. Electrical connection is maintained between the working electrode and the counter electrode via an electrolyte present within the housing. The electrochemical gas sensor preferably further comprises circuitry for maintaining the working electrode at a potential in the range of approximately 1025 to approximately 1400 mV versus the normal hydrogen electrode. The present invention also provides a method of using such a sensor to detect hydrogen chloride.

Abstract: The present invention provides an electrochemical sensor for the detection of hydrogen cyanide. In general, the electrochemical sensor includes a housing having disposed therein a working electrode, a reference electrode and a counter electrode. The electrochemically active surfaces of the working electrode and reference electrode preferably comprise silver. Electrical connection is maintained between the working electrode and the counter electrode via an organic electrolyte present within the housing. The electrochemical gas sensor preferably further comprises circuitry for maintaining the working electrode at a potential in the range of approximately +40 mV to approximately -40 mV versus the silver reference electrode. Most preferably, the electrochemical gas sensor comprises circuitry for maintaining the working electrode at a potential of approximately 0 mV versus the silver reference electrode.

Abstract: A method of stabilizing borane-tetrahydrofuran complex comprises the step of maintaining the temperature of the borane-tetrahydrofuran complex at or below 20.degree. C. A method of reacting a borane reagent with a substrate comprises the steps of heating the borane reagent and the substrate in a reaction vessel and preventing escape of evolved diborane from the reaction vessel. Preferably, a reaction vessel containing a borane reagent and a substrate is maintained under at greater than atmospheric pressure with back-pressure regulation.

Abstract: The present invention provides an electrochemical sensor for the detection of hydrogen cyanide. In general, the electrochemical sensor includes a housing having disposed therein a working electrode, a reference electrode and a counter electrode. The electrochemically active surfaces of the working electrode and reference electrode preferably comprise silver. Electrical connection is maintained between the working electrode and the counter electrode via an organic electrolyte present within the housing. The electrochemical gas sensor preferably further comprises circuitry for maintaining the working electrode at a potential in the range of approximately +40 mV to approximately -40 mV versus the silver reference electrode. Most preferably, the electrochemical gas sensor comprises circuitry for maintaining the working electrode at a potential of approximately 0 mV versus the silver reference electrode. The present invention also provides a method of using such a sensor to detect hydrogen cyanide.

Abstract: A deformable, pad-type filter is provided which does not have a frame but instead uses two filter elements, at least one having a non-planar configuration in a stress-free condition, which are preferably joined along an outer edge to form an inner chamber. A connector is located in and attached to one of the filter elements, the connector having a rigid connector platform which projects radially outward from the connector to enable a user's fingers to grasp the perimeter of the connector platform to twist or otherwise manipulate the filter for connection or disconnection to a respirator facepiece without damage to the filter material.

Abstract: The present invention provides a full body harness which utilizes a reduced number of components thereby simplifying construction and reducing manufacturing costs. The harness has only four pieces of webbing, two identical shoulder straps and two identical leg straps. These shoulder straps and leg straps are connected to two uniquely designed, multi-functional hip plates. The harness also has a standard back pad and a standard shoulder strap retainer.

Abstract: The present invention provides an adjustable headband for protective headgear with a ratchet mechanism having different resistances. The adjustable headband utilizes a ring gear assembly having a plurality of radially projecting teeth thereon. Each of the projecting teeth of the ring gear assembly has a first tooth side and a second tooth side which is different from the first tooth side. For example, each tooth of the ring gear assembly preferably has a first tooth angle on the first tooth side and a second, different tooth angle on a second tooth side. A spring assembly having at least one spring tooth projecting radially therefrom is connected to the adjustment knob. The spring assembly is positioned such that the at least one spring tooth meshes with the teeth of the ring gear assembly to provide resistance to the rotation of the adjustment knob.

Abstract: Accordingly, the present invention provides an electrochemical sensor comprising at least two electrochemically active electrodes, a non-aqueous electrolyte system and a diffusion barrier membrane through which the analyte in its gas phase is mobile but through which the non-aqueous electrolyte system is substantially immobile. The diffusion barrier membrane thus allows an analyte in its gas phase to enter the sensor, while substantially preventing the non-aqueous electrolyte from exiting the sensor.