Abstract: A make-up air handler for supplying outside air to clean environments such as clean rooms in semiconductor fabrication facilities includes a flow passage through which the outside air is passed. At least one filter is disposed to filter the outside air passing through the flow passage. The make-up air handler preferably includes all boron-free filters to prevent the introduction of boron into the outside air by the filters. The make-up air handler can include boron-free ULPA filters to provide highly clean boron-free outside air for supplying to clean environments. The make-up air handler can be operated in a normal manner at air velocities exceeding the rated velocities of the ULPA filters, without subjecting the ULPA filters to air velocities exceeding their ratings, due to the configuration and arrangement of the ULPA filters in the flow passage.

Abstract: A safety cabinet having a work area defined by an enclosure and including an air circulation and cleaning system. The air circulation and cleaning system includes a plurality of air plenums and passageways through which air is circulated by a blower assembly. A portion of the air exiting the blower is directed through a transition boot and exhaust plenum and a remaining portion of the air exiting the blower assembly is directed into the work area through a perforated divider plate and a supply plenum. The transition boot between the exhaust and supply plenums include resealable fasteners disposed along a seam between first and second ends thereof and around a first end thereof which is attached to the exhaust plenum.

Abstract: A ventilator hood including an air blower suitable to draw fumes emanating from a fume producing apparatus through a contaminate filter, a charcoal filter, and a HEPA filter including filter condition indicating means, fire suppression means, and special adapter plate means for directly connecting the ventilator hood to the fume producing apparatus.

Abstract: This invention pertains to equipment used in the custom fitting of golf clubs and in particular to a dustfree workbench for use by a golfsmith for customizing golf clubs having shafts manufactured from graphite, titanium or beryllium. The workbench includes a filtration system particularly designed for removal of the extremely fine particles generated in the cutting of golf club shafts, and characterized by the use of a series of high efficiency filters that the dust-laden air is passed through before being returned to the room. Grates placed within the upper surface of the workbench prevent larger items from passing therethrough and include dampeners for purposes of flow regulation. The filter assembly comprises a plurality of filter elements with various micron rating filters, referred to as coarse and fine, and assembled in order of decreasing porosity and placed in series and upstream of the blower.

Abstract: A clean room includes walls, a floor and a ceiling which define the room. An air delivery system having a HEPA filter, a fan and an air return duct in communication with the filter, is provided to maintain the air in the room clean. A shield of the present invention is mounted in the room over a work surface to form a clean zone over at least a part of the table. The shield is mounted so that at least a part of the filter is within the clean zone so that filtered air will be forced into the clean zone. Accessories, such as an IV bar and a light panel may be provided with the shield to facilitate working in the clean zone. The shield creates a clean zone in the clean room having a higher class rating than the clean room rating without the use of additional HEPA filters and without the use of traditional laminar flow hoods.

Abstract: Energy conservation structure is provided for a controlled environment room having an opening in a wall thereof through which work is passed and through which room air under pressure may be discharged from the room, thereby to prevent contamination of the room air by contaminants in outside air entering the room through such opening, the energy conservation structure including structure providing suction adjacent to the wall opening to induce the flow of room discharge air thereto, the latter structure being constructed and arranged for communication with structure and apparatus for recycling the discharge air of such induced flow to the controlled environment room.

Abstract: A particulate removal apparatus for use in soldering operations having a housing with an inlet opening formed therein and an interior cavity, a filter positioned within the housing for removing particles from air passing therethrough, an impeller positioned within the interior cavity of the housing, and a motor positioned within the interior cavity of the housing and positioned between the impeller and the filter. The impeller has backward inclined impeller blades. The impeller pulls air through the inlet opening and directs the air toward a wall of the interior cavity. The impeller blades generally surround the interior opening. The filter is a HEPA filter positioned within a framework within the housing. The HEPA filter is arranged in an accordion-style folded configuration within the framework.

Abstract: A workbench suited for welding, grinding, and polishing operations features a multi-panel table top. The panels each have a high number of perforations to allow a high rate of air flow at a relatively low noise level. An optional backwall or a booth can be mounted atop the tabletop. Each also has perforations to collect dust from the air flow.

Abstract: An air treating system filters and dehumidifies contaminated air within an industrial plant. The air treating system includes a prefilter, a filter, a blower and an evaporator. A self-contained filtering unit directly communicates with a flume which receives fluid carrying contaminated particles from a machining center. Multiple self-contained filter and dehumidifier units are coupled with a single air conditioning compressor and condenser unit.

Abstract: A system and method for recovering vapors in industrial washing equipment, wherein a solvent is used to wash various articles within a wash area of the equipment. The system includes a hood supported above the wash area, a motor driven fan mounted within the hood for creating an envelope of negative pressure between the wash area and the hood to draw rising vapors into the hood and to direct the vapors at high velocity against a surface to cause separation of pure solvent liquid droplets from the vapor through impaction, and a coalescer for gathering the separated droplets of pure solvent prior to directing the pure solvent to a holding tank for reuse in washing operations.

Abstract: An Analytical Glove Box System has a sealed instrumentation enclosure, a ve box having an injection port coupled to the instrumentation and an air lock through which sample vials can be passed from outside into the glove box. A pump is provided for withdrawing gas from the glove box enclosure through a filter system so that the glove box is maintained at a negative pressure with respect to ambient. Toxic chemical samples can thus be safely handled by an operator and analyzed with sophisticated instrumentation without the risk of contamination. All effluent from the glove box is filtered before release to ambient, leakage from the glove box is further eliminated due to the negative pressure differential maintained, and the instruments are isolated from the potentially contaminated environment of the glove box. The system further provides the ability to conduct highly toxic chemical analysis in field locations since it is portable (including air transportable) and is easily decontaminated.

Abstract: A smoke removal device, especially designed for use in welding, having one or more portable funnels, with a wide opening through which suction may be directed to remove smoke from particular areas where combustion is taking place, and a narrow opening opposite to the wide opening, a vacuum device for creating the suction by which the smoke is removed, the vacuum device having an inlet valve for each funnel, and hoses connecting the narrow opening of each portable funnel to one of the inlet valves of the vacuum device. In a preferred embodiment, the portable funnel is connected to a base containing magnets. The funnel is connected to the base by a first cylinder extending downward from the funnel, with the first cylinder fitting inside a second cylinder attached to the base, with the funnel and first cylinder being rotatable in relation to the base and the second cylinder. A wheeled, multifilter carriage is provided to clean smoke coming from the funnel before it is exhausted into the surrounding air.

Abstract: A clean air cabinet includes a blower chamber and a sample chamber separated by a filter. A blower within the blower chamber forces air through the filter into the sample chamber. A perforated wall between the sample chamber and the filter provides a pressurized zone between the wall and the filter. An exhaust plenum connects the pressurized zone with an exterior of the cabinet. A cap is provided to close off the plenum when the blower is not operating.

Abstract: An air cleaning system for treating contaminated air from a mechanical industrial process containing a heterogenous multi-component mixed density fluid (e.g., mist, vapor and/or smoke) that addresses the cloud-like behavior of this contaminated air. The air cleaning system continuously captures a contaminated air volume emitted during operation of the mechanical industrial process and mixes that contaminated air volume with an ambient air volume in order to produce a mixed air volume having certain characteristic temperatures and air velocities. The characteristics of the mixed air volume are controlled such that the mixed air volume does not exhibit cloud-like behavior when transferred via a conduit structure to an air cleaning apparatus or the like.

Abstract: A source capture system for capturing contaminated air from an industrial process includes structure both for continuously capturing a contaminated air volume emitted during operation of the industrial process and for mixing that contaminated air volume with an ambient air volume to produce a mixed air volume which is then transferred to an air clean apparatus or the like. The source capture system recognizes that air volumes will exhibit different characteristics traveling through an air treatment system, and that certain of those characteristics such as cloud-like formation and contaminated air volumes having significant gaseous phase vapor components are undesirable and operate to decrease the overall effectiveness of the air treatment system, regardless of what type of technology is used for the air cleaning apparatus.

Abstract: An air cleaning system for treating contaminated air from a mechanical industrial process containing a heterogenous multi-component mixed density fluid (e.g., mist, vapor and/or smoke) that addresses the cloud-like behavior of this contaminated air. The air cleaning system continuously captures a contaminated air volume emitted during operation of the mechanical industrial process and mixes that contaminated air volume with an ambient air volume in order to produce a mixed air volume having certain characteristic temperatures and air velocities. The characteristics of the mixed air volume are controlled such that the mixed air volume does not exhibit cloud-like behavior when transferred via a conduit structure to an air cleaning apparatus or the like.

Abstract: The present invention provides a smoke-eliminating device of simple construction which can easily be installed onto a preexisting casino gaming table. The fan for circulating air during the purification process is located beneath the gaming table to thereby reduce noise and increase the amount of usable area surrounding the gaming device. The smoke-eliminating device of the present invention is placed between the outer edge of the gaming table and a padded rim above this outer edge. Spaces are placed between the padded rim and the outer edge of the gaming table, to thereby vertically raise the padded edge. The space created between the padded rim and the gaming table is filled with intake vents and the spacers. An air circulator and purifying device is located beneath the table and conduit connects the intake vents to the air circulator and purifying device. The intake vents thus remove cigarette smoke from near the gaming table, purify the air, and release the purified air beneath the gaming table.

Abstract: A self-exhausting welding station includes a frame assembly with a generally rectangular platform frame mounted on legs. An exhaust system includes a filter cabinet mounted on the platform frame and including a series of filter panels which can be successively finer. A motorized fan is connected to a downstream side of the filter cabinet in communication with an outlet opening thereof for drawing an air flow through the filter cabinet and the filters mounted therein. A work area assembly is placed on top of the frame assembly over the filter cabinet and includes a work surface with slot perforations through which exhaust from welding operations and the like can be drawn downwardly by the exhaust system for passage through the filter cabinet wherein the exhaust gas is filtered prior to discharge.

Abstract: A minienvironment provides a cleanroom-type environment by maintaining an ultra-filtered clean-air material handling area to minimize or eliminate the exposure of materials to harmful microcontaminants. The minienvironment includes an air flow generator assembly for directing air external to the minienvironment through a filter assembly into a material handling area. A diffuser redirects this filtered air flow over the material handling area in more than one direction to minimize or eliminate the exposure of any surfaces of materials in the handling area to harmful microcontaminants. The resulting continual outward flow of ultra-filtered air over this handling area prevents harmful microcontaminants in the air external to the minienvironment from directly entering the handling area and flushes out any harmful microcontaminants generated within the handling area.

Abstract: An air filtration apparatus includes a lower intake duct and an upper exhaust duct interconnected by a telescoping vertical pipe section permitting vertical length adjustability of the exhaust duct relative to the intake duct. A blower is mounted in the vertical pipe section to draw air through an intake opening in the forward end of the intake duct, through the vertical pipe section and outwardly through an exhaust opening in the bottom surface of a forward end of the exhaust duct. Particulate filters are mounted in the intake and exhaust openings. A length adjustable upright extending between the intake duct and exhaust duct permits selective adjustment of the height of the exhaust duct over the intake duct. A filter rack on the forward end of the intake duct includes a clamping apparatus which permits various sizes of filters to be inserted in the filter rack.

Abstract: A casino gaming table provides a smoke-free environment for the casino operator by discharging an air curtain or air barrier of purified filtered air. The gaming table includes a filter assembly which withdraws smoke contaminated air from ashtrays and smoking patrons who are playing the casino game. The purified filtered air is discharged adjacent the casino operator to provide a breathing zone free of cigarette smoke and related pollutants.

Abstract: A ventilated gaming table assembly includes a gaming table component, a rail component and a plurality of electric ventilating fan subassemblies mounted about the periphery of the table and operable selectively by individual players.

Abstract: The blow off unit is an open top box with the front lower than the sides and back. A splash shield is placed at an angle at the back of the work area to deflect the blow off air stream and debris down into the collection filter. A space is left behind the splash shield to allow the blow off air to escape after it passes through the filter. The filter is a standard HVAC bag type air filter which hangs down into the box with its frame resting on the angle frame of the unit. A wire grill covers the filter for protection and to provide a place to lay parts. In use, the operator holds the part in the work area of the unit with one hand and blows the coolant and debris from the part down into the filter. The blow off compressed air is the only power source required for the unit. When the filter becomes dirty and/or saturated with coolant, it is replaced with a new one.

Abstract: A dust arrester for a sanding machine includes a hollow workbench and a tubular filter unit which is axially rotatable inside the hollow workbench. A suction unit draws polluted air into the workbench to be filtered by the filter unit. A blowing unit is disposed inside the filter unit and generates a downwardly oriented air stream to blow dust particles collected by the filter unit into a removable dust receiving bin inside the workbench. The dust arrester is simple in construction, has a relatively low cost, and can effectively control air pollution.

Abstract: Surgical procedures are conducted in a protected environment wherein a laminar flow of micro filtered air is passed from a top to a bottom of an enclosure with transparent panels defining a space for manual access of the surgeon's hands and arms. Air circulation is forced through a high performance HEPA filter between an inlet including the bottom of the enclosure and an outlet at the top, both including panels with an array of apertures for establishing substantially laminar flow. A duct along an endwall of the enclosure carries filtered air to the top. A positive pressure differential is maintained between the inside of the surgical compartment and the outside, to protect the patient operative site from contamination by airborne particles. The enclosure rests on top of a mobile cabinet and has access ports for connection lines and also for bringing the surgical subject into the enclosure. For experimental animals, an access port for cage boxes can be provided.

Abstract: An adjustable cabinet having a built-in ventilation and air purification unit for portability and versatility when used in conjunction with modular work stations. The adjustable cabinet can expand and contract in size and be moved as needed for varying storage requirements or furniture arrangements of the work station while still providing ventilation to the work area.

Abstract: A vacuum box is for collecting small particles or the like. the vacuum box includes a cabinet having a front, a rear and a hollow interior. The front of the cabinet includes a substantially horizontal working surface at a lower region thereof. The working surface includes an air inlet opening therethrough. A motor and fan are disposed within the hollow interior of the cabinet at the rear thereof for the discharge of air from the hollow interior of the cabinet. A collection compartment is disposed below the working surface and the air inlet opening therethrough with a rear portion of the collection compartment being disposed within the interior of the cabinet. A filter is disposed within the interior of the cabinet between the collection compartment and the fan. The fan causes the air including the particles produced at the working surface to be drawn downwardly through the air inlet opening into the collection compartment, upwardly from the rear portion of the collection compartment, and through the filter.

Abstract: A load chamber of a load lock is provided with a vertical air curtain which isolates the load chamber from the general clean room environment. Horizontal air flows generated in the load chamber bathe wafers held horizontally in the chamber with filtered air. These horizontal air flows are captured by the air curtain and recirculated to filters which provide horizontal and vertical air flows in the load chamber. If desired, the vertical and horizontal flows may be driven by the air supply mechanism of the clean room itself.

Abstract: A laminar flow work table has a perforated work surface positioned and supported a predetermined distance above a floor surface. The perforated work surface is divided into sections. Each section communicates with a separate duct communicating with the perforations in its respective section and extending to a common exhaust manifold connected with a return duct in a ventilation system where the table is situated. Each section of the work surface is ventilated by drawing fluid through the perforations into the ductwork and out to the return duct through the common manifold. Each duct has a baffle which controls the flow of fluid in its respective duct which permits the ventilation in various parts of the work table to be balanced. This arrangement permits the work table to be adequately and uniformly ventilated so that noxious fluids may be effectively removed from the vicinity of the work table so that a worker is not exposed to dangerous, unpleasant, or unhealthful conditions.

Abstract: A solder assembly for facilitating soldering operations includes a stand having a pivotally mounted soldering iron rack for receiving and supporting a soldering iron plugged into a power outlet socket on the stand during periods of non-use. The soldering iron rack is arranged to operate a switch upon withdrawal of the soldering iron from the rack for use to activate a motor driven fan housed in a hood supported above the stand by an articulated member on the stand. The fan upwardly sucks the noxious gases produced by the soldering process through an activated charcoal filter positioned an a trumpet-shaped air passage defined by the hood for discharge through a nozzle rotatably and angularly adjustably mounted in the exhaust outlet port of the hood. A lamp manually energized by a separate switch is provided in the hood to illuminate the work area. A sponge pad and a solder reel support strut are provided on the stand.

Abstract: A ventilated work station for sculpting fingernails includes a horizontal work platform supported at its opposite ends on pedestals, one of said pedestals containing at least one drawer for storing tools and supplies, and wherein the at least one drawer is reversible in the pedestal to convert the work station from the left-hand configuration to a right-hand configuration. A transparent hood is supported on and covers a portion of the platform and has low profile access slots in opposite sides thereof for insertion of the hands of a nail technician and a customer. That portion of the platform beneath the hood has slots therethrough for conveying heavier than air fumes downwardly through the platform, and the hood captures lighter than air fumes. An exhaust fan is connected with ducts leading to the hood and slots for producing a low pressure in the area confined by the hood to convey collected fumes away from the work area.

Abstract: A clean air cabinet is disclosed including a cabinet shell defining a cabinet interior. Internal walls including a ceiling, back wall and floor are disposed within the interior and define a work area. A first plenum connects a blower outlet with air passages formed through the ceiling. A first high efficiency particulate air (HEPA) filter is disposed within the first plenum. A second air plenum connects air passages formed in the floor with a blower inlet. A third plenum connects air passages formed in the work area back wall with an exhaust opening formed through the cabinet shell. A second HEPA filter is disposed within the third plenum.

Abstract: A compact wafer carrier for storing spaced semiconductor wafers in parallel with each other, is provided for fabrication processes of a semiconductor device requiring a high particulate contamination control. The wafer carrier has an air cleaning device, including a secondary battery as a power source, a motor fan, and a particulate air filter, and a storing chamber directly connected to the air cleaning device for storing the wafers. The storing chamber has a first opening for receiving the filtered air flow, and a second opening for loading and unloading the wafers, both openings facing each other. As a result, the major part of the filtered air flows in a laminated stream passing along the surfaces of the wafers stored with a fairy high speed, serving to protect the wafers from the intrusion of the particles contained in the environmental air, and removing the particles originally adhered to the surfaces of the wafers.

Abstract: A method of providing clean air to a workpiece comprises positioning the workpiece adjacent to a first opening in a conduit. The conduit includes a central segment and a peripheral segment having, respectively, the first opening and a second opening disposed at opposite ends of the conduit. The peripheral segment surrounds the central segment such that the first opening is substantially coplanar with the second opening. A laminar flow of air is created through the conduit in a direction away from the second opening and toward the first opening. The air flow is filtered through a HEPA filter supported within the conduit.

Abstract: An arrangement for cleaning gaseous atmosphere from a plurality of separate, contained working spaces by removal of noxious, in particular radioactive, gases, such as tritium. Each working space is provided with an individual gas circuit having a circulation pump. Each gas circuit contains a regenerable absorption device, for separation and temporary intermediate storage of the gases to be removed as well as a device for release of the intermediately stored gases. Moreover, a common gas removal unit is provided which can be connected selectively with the separation and intermediate-storage device of each working space circuit and which contains a vacuum pump arrangement for drawing off the gases released in the separation and storage device connected at the time, a vessel for receiving the drawn-off gases, and a device connected with the vessel for binding the gases to be removed.

Abstract: An apparatus for recovering gold from gold-containing mixtures by forming a gaseous effluent of said mixture and bringing it into contact with baffles which are arcuately disposed in series so as to divert the gold onto collecting trays. The trays are disposed within a chamber in such manner as to create pathways for the effluent so that divergent streams of said effluent are directed to the baffles to enhance the recovery operation.

Abstract: Apparatus for removing dust from the atmosphere around an externally heated tube (1) having a deposit being made on its inside surface from a vapor phase, said dust being removed by setting up a laminar flow of dust-free air around the tube. The apparatus includes members (7, 8, 9, 10) for setting up laminar air flows in planes parallel to the axis of the tube and on either side thereof, together with members (15, 16) for setting up flows of air perpendicularly to the axis of the tube and on either side thereof.

Abstract: Apparatus and method for removing obnoxious fumes and particulate laden air from a work area above a table or desk for the treatment of human nails. The removed air is filtered in a unit removed from the table or desk to remove particulate 3 microns and larger in size and the fume laden air is diffused into the environment at a location remote from the work area and in a concentration sufficiently low to avoid discomfort to those present in the area.

Abstract: A central core unit for ventilating and providing utility connections to peripheral workspaces disposed adjacent at least one electrical terminal, includes a cabinet having walls for enclosing the electrical terminal, a workspace fan mounted in a side wall of the cabinet, the workspace fan being operable to draw air from the workspace into a plenum defined by the walls of the cabinet, an air filter mounted in one of the walls of the cabinet, the air filter cleaning air drawn in by the fan and discharging the air back into the workspace and at least one electrical outlet mounted in one of the walls of the cabinet, the outlet providing connection to the electrical terminal through the cabinet.

Abstract: A smoke-free working area is described in connection with a table having a recirculating air system. The table base comprises a sealed air chamber pressurized by a motor and filter system. Openings located on the surface of the table allow air to be dispensed at a controlled rate which travels up and is collected by a network of air ducts that support a canopy. A return path for the air is fed through a hollow support member that is connected at one end to the air ducts and at the other end to the motor and filter assembly thereby completing the flow path. Smoke and other pollutants are carried into the system and filtered in a continuous fashion, thereby providing a continuous smoke-free environment for other persons located adjacent the smoke-free table area.

Abstract: A moveable welding station. An exhaust hood mounted atop a pair of depending legs with a welding curtain extending downwardly from the hood and defining the work area. An exhaust fan mounted to the hood pulls air upwardly from the work station through a bottom slot and then radially into a plurality of cylindrical air filters. An air passage is provided from the hollow central portions of the cylinders upwardly through a pair of charcoal filters exiting into the ambient air surrounding the welding station. A second source of pressurized air is directed via air tubes into the hollow central portions of the cylindrical filters in a direction opposite of the normal air flow in sequential pulsed fashion dislodging foreign particulate matter from the cylindrical filters. A dust pan removably mounted to the hood receives the foreign particulate matter allowing for the automatic cleaning of the filter.

Abstract: A worktable, in particular a dental laboratory workbench which includes a work block arranged at front side of the table, and a vacuuming device forming a unitary structure with the work block for vacuumable material or waste which is obtained during the processing or finishing of workpieces.

Abstract: Dust recovery apparatus is disclosed which recovers air-entrained dust in a high state of purity. The apparatus comprises a housing capable of sustaining at least slight positive pressure and suitable for accommodating powder processing machinery, an air supply system for passing air at a predetermined rate and at a slight positive pressure to the housing, a collector which collects dust entrained in air leaving the housing and an air-flow rate sensor which detects air-flow rate in the apparatus and activates valves for stopping air passing to the collector when the air-flow rate falls outside a predetermined range.

Abstract: Clean bench having an outlet wind velocity measuring apparatus for the filter. The measuring apparatus comprises an air duct on a downstream of the filter, a rectifier means at the passage of the air duct, and a wind velocity sensor for detecting the velocity of the outlet wind rectified by the rectifier means.

Abstract: A modularized biohazardous fume hood in which a single unit retains a blower, and exhaust transition, and mount for the blower in a single package. The exhaust transition rides atop a non-metallic exhaust HEPA filter and therefore the non-metallic filter serves as a spacer as well as a sound and vibration deadener from the motor of the blower. Similarly, the base of the motor rests atop a second filter through which the recirculating air is driven downwardly over a diffuser and onto a work tray. The entire blower and exhaust transition rests atop the non-metallic HEPA filter, and therefore further sound and vibration deadening and space saving is achieved.

Abstract: Disclosed is a portable apparatus which adsorbs trace toxic fumes for a wide diversity of situations. The apparatus consists of a gas-tight enclosure, attached flexible duct and floating support arm, adsorbent filter, exhauster blower and quick disconnect fasteners. The blower sucks the toxic fumes through the filter and discharges the treated air back into the laboratory. The flexible duct/floating arm captures the toxic fumes in a wide range of conditions and the quick disconnect fasteners permit the rapid replacement of spent filters. It is the quick-disconnect fasteners between the cover of the box and between the filter and the cover which permit rapid replacement of the spent filters. This flexible apparatus minimizes interference with visual and hand operations, conserves room energy, removes particulate by both the change in direction designed in the apparatus and the non-woven fabrics used to support the adsorbent particle bed.

Abstract: There is described a dust exhaustor for a precision-mechanics work table which can be fitted as a ready-to-connect unit beneath the work top of a conventional work table. For this purpose, the housing is L-shaped, the suction opening being in the front end of the substantially horizontal leg of the housing and the large-surface outlet(s) being in the vertical leg of the housing. The housing bounds, in its installed position, the foot or knee region for the user of the work area.

Abstract: A module for providing a work area in which one or several people can perform tasks requiring ultra-high efficiency air filtration. The work area is bounded above by a filter module through which a vertical laminar flow of air occurs from one or more HEPA filters. From the perimeter of the module flows a curtain of air in an enclosing and substantially parallel relationship to the laminar flow air to extend the laminar air zone to the floor. The air curtain also passes through a HEPA filter prior to discharge. The angular direction of the air curtain is adjustably controlled by a unique nozzle structure so that when the air curtain contacts the floor turbulence is substantially eliminated and a sweeping action away from the work area is effected. Separate blower systems supply air for the laminar flow air and the enclosing air curtain at differential velocities.

Abstract: A method and apparatus (1) for control of airborne particulates in enclosed spaces, wherein air is made to flow in parallel airstreams (F), with velocities of the streams selectively graded across the work space (W), so that the integrity of the air flow pattern is better preserved while encountering obstructing objects (6) that lie in its path; and so that any particle introduced into a stream remains entrained and airborne over a longer distance along the clean-to-dirty axis (X). The velocity gradient is achieved by a filtering device (1) comprising a plurality of pleats (25) each pleat having a different surface area.

Abstract: A filter assembly for clean air installations includes a block of high efficiency particulate air (HEPA) filter material adhesively bonded and sealed within an imperforate rigid thin-walled side frame which extends axially beyond the inlet surface of the filter block and thus provides an integral plenum chamber volume as part of a self-contained filter subassembly. The side frame has peripheral cover and supporting flanges at its inlet and outlet ends and can thus be conveniently assembled with and removed from a reusable cover member and cover gasket for the plenum chamber and a reusable perforated outlet grill and one or more peripheral outlet sealing gaskets, all of which constitute parts of a complete filter assembly which can be readily supported by a standard or special ceiling or wall grid or frame assembly.