Abstract: A workbench filtering station (10) includes a generally open interior in which a plurality of filter bags (50) are disposed to partially clean a gas stream. The gas stream is communicated to the bag filters (50) through an air intake (46). The air intake (46) is in the form of perforations in the side walls (44) of the filtering station (10). The station (10) includes HEPA-filters (60) which receive the partially-cleaned air from the bag filters (50). The HEPA-filters (60) clean the air to a clean-room environment. A fan (30) draws a constant volume of air through the filtering station (10) and exhausts the clean air into the room. In operation, a constant volume of air is drawn into the filtering station through the side intake panels. The air is communicated to a first filter station which is in the form of bag filters. The air is then passed through a HEPA-filter stage for further cleaning and exhausted to the room.

Abstract: An inertial-electrostatic wet precipitator for removing particulate contaminants from a gaseous stream passing through a collector tube having a discharge electrode assembly coaxially disposed therein to establish an electrostatic field between the assembly and a liquid film on the inner surface of the tube which acts to ionize the particles in the gas. Liquid for flushing the particles is fed through a pipe spiralled about the precipitator tube, the pipe terminating in a nozzle ejecting the liquid tangentially into the inlet section of the tube to impart cyclonic motion thereto. As a result, liquid is caused to flow against the inner surface of the tube in a helical path to produce the liquid film which flows toward the outlet section of the tube and is discharged into a sump.

Abstract: Disclosed is an apparatus which attaches to an automatic tissue processor to confine and treat the toxic fumes emanating from solvent containers used in a tissue processor. The apparatus consists of a framework clamped on the tissue processor upon which an adsorbent filter and exhauster/blower assembly are mounted and a transparent flexible cover are placed. The blower sucks the toxic fumes and intake air through the adsorbent filter where the fumes are removed from the air. The clear flexible cover has zippered panels with attached fasteners to observe tissue processor operation and provide the technologist access to the tissue processor for operation and maintenance.

Abstract: A filter assembly for filtering air comprises a filter housing and a filter which is removably positioned within the housing. The filter housing includes spaced-apart first and second housing portions which are connected by connecting members on opposite sides of the housing, and the filter is positioned between the two housing portions. One end of each of the connecting members is secured to the first housing portion, and the other end of each connecting member is connected to the second housing portion in a manner which permits the second housing portion to be moved along the connecting members toward and away from the first housing. When the second housing portion is moved away from the first housing portion, the filter can be removed.

Abstract: A work bench and air filter unit are combined in the present invention in a compact configuration by locating two or more air filter units below a work bench and arranging two or more air filter units in parallel with an extraction fan. An improved extraction efficiency is achieved by providing an enclosure located above the work bench wherein the back wall of the enclosure is angularly inclined forwardly at an angle of about 75.degree. with respect to the work platform, an air extraction slot being formed in the back wall communicating with an air plenum which is disposed rearwardly of the back wall through which air is withdrawn from the enclosure.

Abstract: A method is disclosed for recycling industrial air. Air contaminated by particulates is removed from the area of machinery, transported to dust collectors, and filtered. A small portion of the filtered air is discharged to the outside atmosphere while a substantial portion is recycled to the area of the machinery. Significant savings of energy are realized while less particulates are exhausted with the air into the atmosphere as contaminants.

Abstract: A workstation (10) includes a working area (12) inside an enclosure (11) to which an operative can gain access via an access aperture (13) beneath a transparent window, an air circulation system, including a fan (16), being provided for drawing air from the enclosure (11) and directing it back to the enclosure (11) via a filter (15), an outlet being provided downstream of the filter for diverting a proportion of the clean air from the filter (15), so as to cause a lowering of pressure inside the enclosure (11) sufficient to cause an inflow of ambient air via the access aperture (13). The outlet is connected to the atmosphere via a secondary fan (32) which is actuate by a contamination sensor (34).

Abstract: The containment of biohazardous substances, which may exist in the streams of sample material that are being separated in air into droplets in a testing chamber of equipment, such as cell sorters and cytofluorometers, is attained by subjecting the testing chamber to negative air pressure, so that inward air flow at the open face of the chamber is sufficient to inhibit biohazardous substances from exiting out from the face of the chamber. A region of air stagnation is created around the sample streams so that the streams are not deflected from their paths, such paths being pertinent to their testing of the biological sample material. The air stagnation region is formed by interposing an air diverter between the sample streams and the air flow exhaust port at the rear of the testing chamber.

Abstract: A laboratory bench assembly having work stations which are retractable into the interior of the bench to provide a clear and unobstructed bench space when not in use; an air flow is created within said bench by a blower, the air flow carrying dust particles from each work station through a conduit into a cartridge-type filter which traps and collects the dust particles; a jet shoots a blast of high pressure air into said filter for cleaning purposes.

Abstract: A sterile air recycling module is mounted to a wall of a room and includes a housing having an outlet for discharging sterile or clean air into the room, opposed grilled inlets for controlling the volume of air drawn into the interior of the housing from the room, and an inlet for fresh air or plant conditioned air, a supply pressure plenum chamber within the housing for discharging air through a high efficiency particulate air (HEPA) filter which is in fluid communication with the housing outlet, and a blower within the housing for withdrawing air from a negative pressure plenum within the housing and an outlet in fluid communication with the supply pressure plenum, the housing inlets being in fluid communication with the negative pressure plenum.

Abstract: The wasteful discharge of heated or cooled room air in a ventilating system to which a number of fume hoods are connected is reduced by making it possible to turn off unused hoods without unduly unbalancing the system and by making it possible, when access windows are closed, to reduce the volume of air flow to below the required open window level. Unconditioned outside air is automatically fed into the system in an amount compensating for the reduction in air available from the hoods when they are shut off or when flow from them is reduced. Switches are provided on the hood windows to change hood damper openings automatically to increase air flow when access windows are open and reduce it when windows are closed.

Abstract: An attachment for laboratory fume hood structures and the like for opening and closing the movable sash member thereof to vary or close the effective size of such access opening, and in particular to move the sash into closed position when the hood is unattended and to open the hood in the presence of operating personnel. The construction is such that the device may be readily attached to most existing fume hood structures and the like with substantially no modification or change in the latter and providing automatic operation when desired as well as manually controlled operation. At the same time the construction is such that the sash member may be manually actuated if necessary. A further improvement provides for the control of the hood exhaust blower, for example to provide high speed operation when the sash is in open position and low speed operation when the sash is in a lowered or closed operation and, if desired, simultaneously therewith the control of an auxiliary air blower.

Abstract: An enclosed fume hood having an access window with a vertically sliding sash is provided with an additional horizontally movable sash which closes off only a fraction of the open window space and thus reduces the volume of air required to be drawn through the window in order to maintain the requisite air velocity while still permitting complete access to the interior of the hood. Provision is also made to permit the horizontally movable sash to be easily removed, when necessary, to permit insertion into the hood of apparatus wider than the residual open window space.

Abstract: This invention relates to a fume hood in which side and top walls define a space enclosed on all sides but the underside, the hood having baffle plates within the space, the plates sloping upwardly and outwardly adjacent the side walls, the plates having their upper edges spaced from the walls of the hood. Suction opening is located in the top wall centrally above the baffle plates.

Abstract: A hood assembly for at least partially defining an enclosure in which two or more non-parallel rapidly moving air streams cooperate to entrain minute air borne particles in the enclosure to recover the latter and prevent the escape of the particles through an opening in the forward part of the enclosure. The air defining the air streams may in whole or in part be discharged to the ambient atmosphere substantially free of entrained air borne particles, or the air may be sequentially recycled through the enclosure. The hood assembly is particularly adapted for paint spray booths, but is equally useful and effective, when the air borne particles constitute smoke or fumes.

Abstract: Contaminated exhaust gases being generated at a work table or work station having one or more open sides adjacent the area above the work table, and normally tending to rise into the atmosphere surrounding the work station, are collected in an exhaust hood which includes an inlet extending parallel to and generally above each of the open sides. A first portion of such exhaust gases collected are passed on to be filtered in conventional pollution abatement equipment; however, a second portion of the contaminated exhaust gases are rerouted, in some cases mixed with fresh outside air, and introduced through an air nozzle directed at the aforementioned inlet to the exhaust hood to improve the exhaust gas collecting, as well as reducing the requisite capacity of the filtration equipment and reducing the intake of make up air from the room surrounding the work table.

Abstract: Contaminated exhaust gases being generated at a work table or work station having one or more open sides adjacent the area above the work table, and normally tending to rise into the atmosphere surrounding the work station, are collected in an exhaust hood which includes an inlet extending parallel to and generally above each of the open sides. A first portion of such exhaust gases collected are passed on to be filtered in conventional pollution abatement equipment; however, a second portion of the contaminated exhaust gases are rerouted and introduced through an air nozzle directed at the aforementioned inlet to the exhaust hood to improve the exhaust gas collecting, as well as reducing the requisite capacity of the filtration equipment and reducing the intake of make up air from the room surrounding the work table.

Abstract: A laminar airflow biological safety cabinet apparatus is disclosed which is convertible by the user for changing the airflow pattern through the cabinet in order to meet different specialized conditions encountered in laboratory work with potentially hazardous biological specimens. Adjustable damper structure is provided adjacent the air outlet of the cabinet for simultaneously varying the amounts of air discharged and drawn into the cabinet, and the laminar flow of downwardly directed air through the work compartment thereof. An air filter is located immediately below the work surface of the cabinet and upstream of the air fan for removing contaminants from the air.

Abstract: A total exhaust laminar flow biological fume hood safety cabinet is disclosed having a closed housing with a viewing panel and access port therebeneath at its front portion. Centrally a work tray is mounted with means permitting air passage thereabout. A plenum chamber connects the lower portion of the housing to the top, and an exhaust blower in closed pneumatic communication with the plenum delivers contaminated air to an exhaust filter for total exhaust. Makeup air means are provided at the upper portion of the housing to deliver filtered air downwardly over the work tray, and the blower capacities, flow rates, and filter capacities are developed to the end that the air passing through the access port exceeds the quantity of filtered makeup air while providing for an access air velocity at least double that of the makeup air velocity.

Abstract: The vapor and particulate matter emitting equipment is enclosed within walls of an electrostatically charged clear plastic sheet material. The enclosures are connected at their tops to hoods which are connected to ducting leading to an exhaust fan. The vapors are contained within the enclosures until they can be evacuated by the fan. The particulate matter is attracted to the electrostatically charged sheet material.

Abstract: A textile or other industrial machine, of the type where one or a plurality of operations generate a gaseous discharge at a work station, is provided with at least one wall leaving at least one open side and includes an exhaust hood on the top which communicates with the air space above the work station. A first fan communicates with the exhaust hood to withdraw smoke, fumes, vapors and steam from the air space and deliver it to the outside. A second fan draws in fresh, unconditioned outside air and delivers it to a delivery nozzle extending along the front edge of a work table in said work station. An air curtain is thus formed between the delivery nozzle and the aforementioned exhaust hood, whereby the smoke, fumes, vapors and steam are confined within the air space above the work table until withdrawn through the exhaust hood.

Abstract: Contaminated exhaust gases being generated at a work table or work station having one or more open sides adjacent the area above the work table, and normally tending to rise into the atmosphere surrounding the work station, are collected in an exhaust hood which includes an inlet extending parallel to and generally above each of the open sides. A first portion of such exhaust gases collected are passed on to be filtered in conventional pollution abatement equipment; however, a second portion of the contaminated exhaust gases are rerouted and introduced through an air nozzle directed at the aforementioned inlet to the exhaust hood to improve the exhaust gas collecting, as well as reducing the requisite capacity of the filtration equipment and reducing the intake of make up air from the room surrounding the work table.

Abstract: Exhaust from a limited zone lying on the axis of a cylindrical exhaust duct and spaced from an unobstructed entrance opening of the duct is produced by injecting a flow of air radially outward from a circumferentially extending aperture surrounding the entrance to the exhaust duct while at the same time sucking air through the unobstructed opening of the exhaust duct.

Abstract: A fume hood is provided having an air intake and an air exhaust communicating with each other through the interior of a fume hood cabinet by way of a by-pass passageway and open front on said cabinet. A plurality of sashes are carried by track means which enable them to move selectively horizontally relative to each other across the open front of the fume hood cabinet to variably open and close the same selectively and relative to the open front. Means connected to the sashes provided for coincidental selective movement therewith to variably close and open the communication of air between the air intake and air exhaust through the by-pass passageway of the fume hood cabinet according to the selective movement of said sashes.

Abstract: Apparatus providing a work area at which one or several people can perform tasks requiring ultra-high efficient air filtration. The work area includes an air passageway throughwhich laminar flow of air occurs from a HEPA filter. The apparatus has a leading edge around the work area from which a certain of air flows in an enclosing and parallel relationship to the laminar flow air to extend the laminar air zone a distance beyond the work surface of the apparatus. The curtain air is passed through a HEPA filter prior to discharge. Dual air blowers supply air for the laminar flow air and the enclosing air curtain. The passageways for the two sources of air are in communication so that if necessary, one blower can be the source for both the laminar flow air and the air curtain. When both sources are in operation the communication means also serves to eliminate undesirable harmonics that might originate from either blower if it were to operate alone.

Abstract: A fume hood includes a polygonal-shaped work top providing three or more equally-spaced work areas. A tubular column with a lower apertured portion is located at the center of the work top for exhausting heavier-than-air gases. A plenum located above the work top and supported by the tubular column is provided with slots located above the work openings for collecting and exhausting lighter-than-air gases. Transparent viewing screens permit inspection of all work locations from a single vantage point. A central pedestal is used to support the hood and to route plumbing and electrical conduits from the floor. The system is easily convertible between up-draft and down-draft exhaust without the need for special baffles.