Abstract: A method for manufacturing a gas mask canister using a HEPA filter media having plastic separating plates inserted into between HEPA filter media at certain intervals. The HEPA filter, impregnated activated carbon, and a pre-filter are accommodated within a cylinder. The cylinder is inserted into a canister having an upper portion and a lower portion detachably coupled together. The impregnated activated carbon, the plastic separating plates and the casing of the canister can be reused, and the rest of elements are burned. A vinyl coating sheet is peeled off from the canister after each use. An indexing tab for recording the number of times of peeling is attached on each of vinyl coated sheets, so that the number of uses can be known.

Abstract: The present disclosure is directed to a gasketless connecting filter adapter (20, 40) for airtight joining of a first filter (23) to a second filter (33). The invention includes a flexible cover element (42) being adapted to seal at a first face surface (41) thereof over the face of a first filter (23), and including a second face surface (55) having a recessed central aperture (59) therein. Disposed in the central aperture (59) are connection apparatus for mating with and securing thereto the second filter such that air passes through the second filter (23) into the first filter (33). The second face surface (55) further includes an integral and axially extending resilient lip seal (39) being adapted to sealingly engage the second cartridge (33). The present invention may be of one or preferably two piece molded construction, of particular cross section.

Abstract: The invention relates to a device for removing one or more undesirable or dangerous substances for the human race from a gas or vapour mixture, the device comprising: a predetermined amount of adsorbent for adsorbing the substances and an odourant for releasing an odour in order to alarm a person, wherein the odourant is arranged in such a manner that the odourant is displaceable by the substances, following a predetermined level of saturation of the adsorbent.

Abstract: A combination respiratory filter and sampling device has been developed which collects airborne contaminants for respiratory exposure measurements. The devices, which fit existing commercial half-mask respirators, are generally smaller and lighter in weight than existing filters, and have low resistance to airflow, so they can be comfortably worn by people performing their normal work duties. Each device consists of at least a front, a middle and a back section which can be independently separated and analyzed by traditional laboratory techniques. The filtering and sampling media thicknesses and types can be adapted to target specific compounds.

Abstract: A combination respiratory filter and sampling device has been developed which collects airborne contaminants for respiratory exposure measurements. The devices, which fit existing commercial half-mask respirators, are generally smaller and lighter in weight than existing filters, and have low resistance to airflow, so they can be comfortably worn by people performing their normal work duties. Each device consists of at least a front, a middle and a back section which can be independently separated and analyzed by traditional laboratory techniques. The filtering and sampling media thicknesses and types can be adapted to target specific compounds.

Abstract: A combination respiratory filter and sampling device has been developed which collects airborne contaminants for respiratory exposure measurements. The devices, which fit existing commercial half-mask respirators, are generally smaller and lighter in weight than existing filters, and have low resistance to airflow, so they can be comfortably worn by people performing their normal work duties. Each device consists of at least a front, a middle and a back section which can be independently separated and analyzed by traditional laboratory techniques. The filtering and sampling media thicknesses and types can be adapted to target specific compounds.

Abstract: A combination respiratory filter and sampling device has been developed which collects airborne contaminants for respiratory exposure measurements. The devices, which fit existing commercial half-mask respirators, are generally smaller and lighter in weight than existing filters, and have low resistance to airflow, so they can be comfortably worn by people performing their normal work duties. Each device consists of at least a front, a middle and a back section which can be independently separated and analyzed by traditional laboratory techniques. The filtering and sampling media thickness and types can be adapted to target specific compounds.

Abstract: A filter element for use in a filter holder having a sealing surface and method of making a filter. The filter being made of a folded material of manufacture having a circumferential sealing rim and having a spacer to keep open the folded areas. The spaced being formed by at least one cover layer folded with the filter. The sealing rim being formed to be received in the sealing surface and with the folds formed by at least one cover layer and the filter material both along and transverse to the folds around the circumference of the at least one cover layer and filter material being pressed into said sealing rim at a temperature above the softening temperature of at least a thermoplastic resin provided in at least one of the layers of the cover and filter material.

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: A combination respiratory filter and sampling device has been developed which collects airborne contaminants for respiratory exposure measurements. The devices, which fit existing commercial half-mask respirators, are generally smaller and lighter in weight than existing filters, and have low resistance to airflow, so they can be comfortably worn by people performing their normal work duties. Each device consists of at least a front, a middle and a back section which can be independently separated and analyzed by traditional laboratory techniques. The filtering and sampling media thicknesses and types can be adapted to target specific compounds.

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.

Abstract: A method and apparatus are provided for use in the delivery of an inhalation anesthetic to a patient while employing a closed loop or re-breather gas recirculation system. The method and apparatus control the system temperature to minimize heat buildup, including heat buildup resulting from an exothermic reaction between a patient's exhaled breath and a scrubbing substance that removes a selected constituent from the patient's exhaled breath. The apparatus includes an enclosure containing a scrubbing substance. The enclosure defines an influent opening for admitting the exhaled breath along a first path into the scrubbing substance and defines an effluent opening through which gases can be discharged from the enclosure. The apparatus also includes a second path adjacent the first path between inlet and outlet openings whereby a coolant fluid can flow along the second path to remove heat from the interior of the enclosure.

Abstract: Disclosed is a filter for a reduced threat chemical/biological protective spiratory device which includes a housing having an air intake orifice and an air exit orifice and which encloses a filtering element which includes a plurality of bonded spherical carbon beads arranged in a open cell type matrix. The filtering element also includes an aerosol and particulate filtering element which is a plurality of electrostatically charged polypropylene fibers.

Abstract: A pleatable filter media, suitable for a use in a respirator for humans, is disclosed comprising a filter material including a meltblown polymeric material, such as polypropylene. A laminate construction is disclosed for the filter material comprising a plurality of layers of the meltblown polypropylene laminated together with adhesive. The filter media is preferably glassless. Protective layers enclose the layers of meltblown polypropylene. Methods of manufacture of pleated material are disclosed wherein the adhesive between the layers is extruded in a particular pattern to provide increased stiffness in the machine direction of the pleated filter media. Methods of manufacture are also disclosed wherein the filter media is pleated before the adhesive has cured, and the adhesive is then permitted to cure while the filter media is maintained in the pleated state.

Abstract: A respirator cartridge having body, cover and filter media elements, and including a sealant dispersion member in one of the body or cover elements. The dispersion member directs the sealant material to the peripheral edge of the filter media without wetting the filtering surface of the media. An improved method for rotational molding filter media in/or for a filter assembly is also provided.

Abstract: A snap-on filter for chemical cartridges is presented which includes a filter element comprising a perforated fiberglass prefilter bonded to a felt filter. The filter element is contained within a filter housing which snaps onto the chemical cartridge of a standard gas mask. The fiberglass prefilter is perforated to provide a passage way for fumes into the interior of the filter as well as the filter surface. The perforations increase the overall surface area of the prefilter for filtration. This feature enhances the efficiency and overall life of the filter element.

Abstract: A filter cartridge incorporates a layer of granular material (4d) for adsorbing gases and/or vapors retained in position by porous retaining elements (4e, 4f, 4g). The cartridge includes a housing (2) and a closure element (3) for closing the housing. The closure element (3) is associated with a compression element (10) which during assembly of the closure (3) on the housing (2) acts against the retaining elements (4e, 4f, 4g) to compress the granular material (4).

Abstract: An accessory device for safety breathing equipment which comprises a generally triangular bag of impervious flexible material tapering downwardly from a wide closed top at which a handle is provided, the bag having a zip-type fastener by which the filter unit of a respirator can be loosely accommodated and supported in a voluminous upper region of the bag equipped with an inlet valve, with a hose which couples to the face mask projecting from the narrow bottom of the bag which tightly surrounds said hose when the bag is closed around the filter unit by means of the zip-type fastener.

Abstract: A gas filter canister housing assembly (20) capable of receiving gas filter canisters (28 or 40) of differing heights. The housing assembly includes first and second housing portions (54, 56) and holding apparatus (60) capable of holding the housing portion together. The first housing portion has a cylindrical extension (70) in which a filter canister may be disposed, and the second housing portion includes a cup-shape end portion (102) and a depending flexible skirt (100) which may be held against the cylindrical portion (70) in various positions of adjustment.

Abstract: A disposable rebreathing canister is disclosed for administering oxygen and anesthesia to patients. The canister essentially comprises a housing for a scrubber, including a manifold plate and a rigid container, and a flexible liner disposed within the rigid container. The liner forms an imperforate barrier between the interior of the rigid container and the manifold plate. A scrubber disposed between the manifold plate and liner chemically reacts with gases conducted to it through one of a pair of coaxial passages formed in the manifold plate. Reacted gases are then moved through a tortuous passage either back to the other one of the coaxial passages or removed through an exhaust port.The interior of the rigid container connects with a source of pressure that allows the flexible liner to be collapsed, thus forcing treated gases, fresh oxygen and anesthesia into the lungs of the patient.

Abstract: A self-rescue breathing apparatus has a radial-flow purifier 3 connected between a mouthpiece and a breathing bag 10. An outer plenum of the purifier is open at both ends, a central conduit is open only at the breathing-bag end. Flap valves 50A and 50B control the flow of gas so that exhaled breath passes radially inwards through the purifying medium which gas for inhalation passes freely up the outer plenum, reducing both the resistance to flow and the heating of the inhaled gas that the purifier (which works by exothermic chemical reaction) would otherwise cause.

Abstract: A sorbent type filter assembly (10) which is made by sequentially placing a first resilient perforated plate (40), a first retention filter (36), a sorbent bed (34), a second retention filter (38), a second resilient perforated plate (42), and a cover (14) within the cylindrical portion (16) of a canister shell (12). The cover (14) is forced downwardly to compress the sorbent bed (34) and to resiliently spring bias or stress the first resilient perforated plate (40). While the parts are held together under compression, an annular edge portion of the cylindrical shell is rolled into a circumferentially extending groove on the canister cover to hermetically and mechanically hold the parts together in their assembled and compressed relationship.

Abstract: A multiple canister mount for receiving at different times different sized bolt connectors of canisters for protective masks and the like. The device comprises a base and a pair of spaced annular rims secured to and upwardly projecting from the base. The inner wall of each rim is threaded with threads of appropriate form, and is of a diameter, so as to receive a canister bolt connector of particular size and having a particular thread form. The device also comprises a centrally disposed valve opening and valve seat secured to the base. Such a device provides a simple effective means for securing canisters, which may have different sized bolt connectors, at different times to the same protective mask.

Abstract: The invention disclosed is an indicator for monitoring the capacity of a CO.sub.2 absorbent to absorb CO.sub.2. The indicator is typically used in association with a closed circuit breathing apparatus, including a container for a CO.sub.2 absorbent. The indicator comprises temperature sensing means immersed in the absorbent, a temperature to voltage converter for converting a sensed temperature reading to an electrical voltage signal, temperature trend processing means for processing said electrical voltage signal into a selected electrical output signal characteristic of a temperature trend; and display means for converting said selected electrical output signal to a predetermined visual display indicative of the capacity of the CO.sub.2 absorbent to absorb CO.sub.2.

Abstract: The invention provides a detector for detecting air components, e.g. contaminations, and in particular noxious or poisonous contaminations, which device comprises a housing in which an air pervious carrier containing a first reagent is arranged, this detector being adapted to draw air to be tested through said carrier so as to expose this reagent to the air, this reagent being influenced by the components to be detected, which carrier is to be contacted with a second reagent which, together with the first one, can bring about a color reaction depending on the fact whether the first reagent has been influenced or not.

Abstract: A gas filter container for housing a filter capable of filtering gases containing toxic components. The container includes a flexible end wall adapted to be positioned against the body of the user and is secured by means of a series of straps, two of which are adapted to be attached to a harness structure, such as a parachute harness, worn by the user, in a readily separable fashion so that disconnection of the harness will simultaneously free the two straps connected to the gas filter container. The flexible end wall includes inwardly-directed projections to space the wall from the filter inlet when the wall is deflected and thereby maintain a communication path to the filter inlet.

Abstract: An improved canister for a filter-type respirator having an end-of-service life warning device which is located in a position such that all air flowing through the canister flows through the warning device after the air has flowed through at least about 50 volume percent of the filtering material contained in the respirator.

Abstract: A carbon dioxide absorbing apparatus having a base containing adjacent inhalation and exhalation passages, a through opening or passage centrally located on the base and in communication with the inhalation passage, a gasket located on the base having a raised lip annular opening coaxial with the through opening, a cannister of carbon dioxide absorbing material resting on the raised lip of the gasket and a cover surrounding the cannister defining an annular passage therebetween which is in communication with the exhalation passage. Pins are removably provided along one or more circles of varying diameters on the base to orient the cannister in proper operative position.

Abstract: A carbon dioxide scrubber device for use in a closed or semi-closed breatg gas circuit in an underwater breathing apparatus having a low rate of gas flow includes a canister having a plurality of spaced, coaxial walls that are heated by associated helical water flow heat exchangers and define axial gas flow chambers in which particulate carbon dioxide absorbent material is confined in contact with the heated walls. The heat exchangers are served by common supply and drain lines through water flow controlling connectors having flow dividing and uniting orifices.

Abstract: A visually observable means for indicating end of service life of hazardous vapor/gas respirator cartridges or canisters is disclosed. A colorimetric indicator in sheet form is positioned along the inner transparent sidewall of the respirator cartridge or canister.

Abstract: An electrolytic device adapted for mounting on the interior wall of a container housing sorbent chemicals for detection and display of moisture content. A sandwich or tab-type probe includes superhydroscopic MgClO.sub.4 or CaSO.sub.4 particles which resist electrical current flow when dry and have a higher affinity for moisture than the sorbent chemicals in cartridges or filters. Moisture intrusion is drawn to the anhydrous MgClO.sub.4 or CaSO.sub.4 particles changing their ohmic resistance and thereby enabling visual and nondestructive detection of the moisture intrusion into the container or cartridge. The probe is spaced away from the sorbent chemicals avoiding the transfer of mechanical stresses and any additional pressure drop through the sorbents, thereby permitting the device to be used in combination with a wide range of sealed containers and air filters.

Abstract: An aerosol respirator cartridge employing a prefilter having the form of a closely spiraled fiberglass mat functioning to distribute captured aerosol particles substantially uniformly therethrough for avoidance of prior art aerosol skin affect and the accompanying increased inhalation resistance.

Abstract: A respirator, comprises, a housing having a wall with a sealable opening which is advantageously located in a cover of the housing. A chemical cartridge is disposed in the housing and it has a material capable of generating oxygen upon being started. A breathing tube is connected into the cartridge along with a breathing bag so that a person's respiratory gases may be directed into the cartridge to the bag and then back through the material of the cartridge which also advantageously retains the CO.sub.2 and enriches the respiratory gas with oxygen. A first starter is associated with the cartridge for starting the material so that it generates oxygen and a second control element is disposed in the container adjacent the sealable wall and it has a starting material therein which may be actuated to generate oxygen so as to provide an indication of whether the oxygen-generating material is operating properly and can perform its function.

Abstract: The respirator comprises a first oxygen-liberating chemical cartridge housing which has a first end with a first opening and an opposite end with a second opening. The first cartridge has a tubular extension adjacent the second end communicating with the second opening and having a lateral air bag opening which opens into an air bag which surrounds the first cartridge. A breathing hose is connected from a mouthpiece which is adapted to be worn by a patient to the first opening of the first cartridge housing. The first cartridge housing also has a breathing tube connected to the second opening of the first cartridge housing and it may be coupled to a similar second breathing tube portion of a second cartridge housing. In addition, the second cartridge housing may be coupled to the air bag or the extension of the first cartridge housing so as to form an airtight seal therewith.

Abstract: Providing visual means for indicating when vapor/gas respirator cartridges have exhausted their capacity to provide respiratory protection at or below a hazardous concentration level. In combination with a vapor/gas indicator adapted to undergo a change in color with contact by an organic vapor or gas, there is provided a catalytic agent for enhancing activation and reaction of the indicator agent.

Abstract: A system and filter apparatus therefore are described for providing substantially bacteria-free, humidified oxygen to a breathing mask or breathing tube. The filter apparatus is hydrophobic and is inserted either at or adjacent the outlet of a humidifier, in the flow line between the outlet of the humidifier and the breathing mask, or at or adjacent the breathing mask, and can be easily replaced when contaminated after a period of use.

Abstract: An electric filter for separating impurities from air including a housing which contains separator plates disposed in spaced relationship and formed of conductive material and alternate ones of said plates are connected to opposite poles of a source of voltage.

Abstract: A flexible polymeric mask, which covers the mouth and at least the lower part of the nose, has exhale-valve means and vertical supporting means for air-intake filter means. The filter means provides a wearer of the mask with air which has passed, in sequence, through, e.g., porous foam, activated charcoal, filter paper, absorbent cellulose and gauze.

Abstract: A colorimetric indicator for use in indicating the impending exhaustion of a vinyl organo filtering device. The colorimetric indicator material consists of activated alumina impregnated with between 0.5 to 5.0% by weight potassium permanganate and is positioned immediately behind a window in a canister or cartridge used in filtering vinyl organo materials.

Abstract: A solid material such as an inorganic carbonate, a salt of a strong inorganic acid and a weak base, or a weak inorganic acid cools gas passing therethrough generated from an azide of an alkali or alkaline earth metal. Toxic, molten particles resulting from decomposition of the azide are trapped and reduced to harmless salts by the solid material.