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 gas sensor for the detection of nitrogen dioxide comprising a housing and a working electrode and a counter electrode disposed within the housing. Each of the working electrode and the counter electrode are fabricated from an electrically conductive carbon. The present sensor also preferably comprises a reference electrode fabricated from an electrically conductive carbon.

Abstract: The present invention provides an electrochemical sensor for the detection of an analyte, wherein the output or response of the electrochemical sensor approximates the dose-response behavior of a living organism upon exposure to the analyte. The electrochemical sensor comprises a housing including an inlet port therein to allow the analyte to enter the housing. The electrochemical sensor further comprises at least a first electrode and a second electrode within the housing. Electrical conductivity is maintained between the first electrode and the second electrode via an electrolyte system present within the housing. The electrochemical sensor further comprises a resistor in series electrical connection with the first electrode and the second electrode.

Abstract: The present invention provides an adjustable, flexible headgear band. The band comprises a first end and a second end which overlap. The first end comprises a plurality of longitudinally spaced slots therein. The second end comprises a resilient fastener formed integrally with the second end. The resilient fastener comprises a channel to slidably receive the first end in overlapping engagement with the second end. The fastener comprises a fastener surface from which at least one flange extends to engage and be seated in one of the plurality of slots of the first end. The fastener surface is resiliently bowable in a direction away from the first end upon application of compressive force to the fastener. Upon application of such compressive force, the at least one flange is unseated from the slot in which it is seated so that the first end can be slid relative to the fastener (and thereby the second end).

Abstract: Synthetic routes for forming alkali metal substituted borohydride compounds include the step of reacting an alkali metal reagent, a hydrogen donor, and a substituted borane. The reactions proceed without the requirement of specialized handling of alkali metal hydrides associated with prior synthetic processes for the production of alkali metal trisubstituted borohydride compounds. A chemical composition comprises solid potassium tri-sec-butyl borohydride.

Abstract: Clamping apparatus for providing a fixed support on a fixed beam or other similar structures wherein outer and inner elongated members are mounted for relative sliding telescoping movement therebetween and are moved by a rotatable threaded bolt and each of the outer and inner elongated members have an inclined surface so that when the inclined surface of the jaws contact the opposite side edges of the fixed beam the facing surfaces of the fixed beam and the outer and inner elongated members are moved into intimate contact.

Abstract: The present invention provides a self-contained breathing apparatus ("SCBA") having a personal alert safety system ("PASS") fully integrated therewith. The PASS is structurally integrated with the SCBA such that it is protected from damage by both the air cylinder and the frame. The integrated PASS device is not only automatically activated when the SCBA is being used but can still be activated manually if the SCBA is not in service. Additionally, the integrated PASS device utilizes a unique electrical/mechanical connection assembly between its various parts which greatly increases its ruggedness and durability.

Abstract: The present invention provides a method of reducing copper oxide to improve its acid resistance comprising the step of reacting cupric oxide with a reducing agent selected from the group consisting of morpholine borane, ethylene diamine borane, ethylene diamine bisborane, t-butylamine borane, piperazine borane, imidazole borane, and methoxyethylamine borane to form cuprous oxide.

Abstract: The present invention provides a respirator filter system suitable for filtering toxic agents, including organic vapors, acid gases, formaldehyde, ammonia, and methylamine as well as pesticides, CS and CN tear gases, dusts, mists, fumes and radionuclides from environmental air to be respired by a user of the filter system. In general, the filter system of the present invention includes a cartridge containing a layer of an unimpregnated activated carbon, a layer of an activated carbon impregnated with sulfate, molybdenum and at least one impregnate selected from the group consisting of copper and zinc, and a HEPA filter. Cartridges containing these adsorbents or adsorbents similar to them (in carbon tetrachloride activity and chemistry) have been discovered to be uniquely capable of filtering a broad range of toxic agents.

Abstract: The present invention provides a low-cost alternative to currently available electrochemical sensors. In general, the present invention provides an electrochemical sensor for the detection of an analyte comprising a first metallic housing member and a second metallic housing member. The first metallic housing member and the second metallic housing member are brought together in sealed connection to create a sealed enclosure therebetween. Contained within the enclosure are a first electrode, at which the analyte reacts, and a second electrode, at which a reaction complimentary to the reaction of the analyte at the first electrode takes place. An acidic electrolyte is also contained within the enclosure of the first metallic housing member and the second metallic housing member.

Abstract: An active primary battery containing a lithium anode; an aprotic organic electrolyte; a separator; and a cathode made of silver (II) oxide, mercuric oxide, or a mixture of silver (II) oxide and mercuric oxide is described. The battery exhibits high open circuit and operating voltage under a wide range of current densities. The open circuit voltage of a lithium-silver (II) oxide battery of the present invention is almost double that obtained in a zinc-silver (II) oxide battery. The packaged capacity density, in amp-hrs/cc, is about twice that obtained in a lithium-manganese dioxide battery or a lithium-iodine battery. The packaged energy density, in watt-hours/cc, is also about twice that obtained in a zinc-silver (II) oxide battery, a lithium-manganese dioxide battery, and a lithium-iodine battery.

Abstract: A microminiature combustible gas sensor and a method of fabricating a microminiature combustible gas sensor are provided in which the catalytically active detector comprises a high surface area refractory catalyst support. A microminiature combustible gas sensor is also provided which comprises a catalytically active detector and a diffusion/flow restrictor for limiting the amount of combustion fuel reaching the catalytically active detector. The restrictor causes the catalytic reaction occurring in the vicinity of the catalytically active detector element to become substantially diffusion limited and reduces the power requirements of the sensor. The restrictor also reduces convective heat losses which may arise because of the large temperature gradient surrounding the catalytically active detector element. Finally, a microminiature combustible gas sensor comprising a flashback arrestor with one or more generally linear capillaries for preventing flashback is provided.

Abstract: The present invention provides a respirator mask having a very soft, compliant facepiece that has several stiffening elements integrated therein. The respirator mask preferably includes an exhalation valve and a pair of filter cartridges. It also has a yolk which complements the facepiece and provides for attachment of a harness to secure the respirator mask to the user's face. The respirator mask is lightweight and extremely comfortable due to the novel facepiece made of three stiffening elements which are completely surrounded by and bonded to a flexible material.

Abstract: A self-contained breathing apparatus having two or more air storage cylinders, each of the cylinders in gas-flow communication with a flexible manifold which is in gas-flow communication with a facepiece. Preferably, the flexible manifold includes a manifold unit connected to a flexible conduit for each of the cylinders such that the manifold unit is located at least partially within an envelope defined by the cylinders. Preferably the other main high pressure operating components are also connected to the manifold unit, including the regulator, pressure gauge, cylinder valve and wheel, pressure relief rupture disk, and low pressure alarm such that they are at least partially, more preferably substantially, and most preferably totally disposed within an envelope defined by the exterior surfaces of at least two of the plurality of cylinders.

Abstract: The present invention provides a sizing guide for assisting in the initial determination of an appropriate size of respirator mask for a user thereof. The sizing guide has at least a first sizing gap having a known width such that comparison of the width of the first sizing gap with the length between a pair of facial landmarks such as the sellion landmark and the menton landmark provides an initial determination of the appropriate size respirator mask for the user which can then be fit tested. Preferably, the sizing guide also has a second sizing gap having a known width different from the width of the first sizing gap.

Abstract: Respirator apparatus 10, comprises a monocoque helmet 11, with a visor 14, which is pivotal between an inoperative raised position and an operative lowered position. The helmet 11 is formed of outer shells 17, 18 joined together along the rim and at strategic locations within the domed area of the helmet but are selectively spaced apart in various regions to provide an air chamber 19, at the rear of the helmet 11 and an air chamber 20 at the forwar part of the helmet. These chambers 19, 20 are interconnected by three ducts 21, 22, 23. The chamber 19, opens through the outer shell and is fitted with an air filter 25, to receive incoming air. The chamber 20 opens through the inner shell 17 and is fitted with a fan 26 to propel air through the ducts 21, 22, 23 into a breathing zone formed behind the visor 14. The rear portion of the helmet is provided with a chamber 29 which is isolated from the ducts 21, 22, 23 and which accommodates batteries for energizing the fan 26.

Abstract: The present invention relates to a respiratory protective apparatus utilizing a powered filtering device having a housing, with at least one inlet and an outlet, and a pump located between the inlet and the outlet for pumping air therebetween. The powered filtering device has a controller, preferably located at or near the outlet of the housing, for adjusting the air flow between the inlet and the outlet in response to a wearer's breathing pattern. Preferably, the controller does this by predicting the future breathing pattern of the wearer based on the past breathing pattern of the wearer. The powered filtering device also has a monitor to determine if the air flow through the respiratory protective apparatus falls below a set level and it does, alert the wearer to this condition.

Abstract: The present invention provides electrochemical sensors for the detection of nitric oxide comprising a housing in which is disposed a working electrode, a reference electrode and a counter electrode. The electrochemically active surface of the working electrode preferably comprises RuO.sub.2. The nitric oxide electrochemical sensors of the present invention are capable of resolving nitric oxide concentrations at least as low as approximately 0.1 ppm and are well suited for use in medical environments because of their insensitivity to many other gases commonly used in medical environments.

Abstract: A metal respirator cartridge which may be completely assembled prior to performing the encapsulation process wherein the periphery of the filter element is completely sealed to the metal cartridge body. The cartridge has a metal cover provided with a unique air inlet opening which performs two distinct functions, that is, as an opening to admit air into the metal respirator cartridge as is normal; and as an opening which, during the manufacturing process, allows a liquid sealant to be introduced into the interior of the metal cartridge body to encapsulate the periphery of the filter element.