Abstract: Embodiments of the invention generally provide a containment system having integrated bubble tight-dampers. In another embodiment, the containment system includes an integral auto-scan mechanism disposed in the housing of the containment system so that a filter element, disposed in the housing, may be leak tested without accessing the interior of the housing. In yet another embodiment, a method for testing a filter disposed in a containment system includes challenging an upstream side of a filter element disposed in a housing of the containment system with a test aerosol, and automatically moving a probe disposed within the housing to obtain samples for leak testing.

Abstract: A filter assembly, having a housing including a housing bottom portion; at least one ring filter element that is received by at least one receiving space defined at least in part by the housing, wherein the receiving space includes a receiving space bottom portion; a cover attached to the housing bottom portion and configured for at least partially enclosing the at least one receiving space and the ring filter element, wherein the at least one receiving space may be selectively emptied when the cover is removed; an outlet located at the receiving space bottom portion within the cover; and a closure located on the at least one ring filter element, wherein the closure is configured to at least partially close the outlet when the at least one ring filter element is inserted into the at least one receiving space.

Abstract: A method and apparatus for carrying out a laser operation, wherein a laser source is provided, wherein lasing gas is supplied from at least one lasing gas source to the laser source for the formation of a laser beam, wherein, with the aid of the laser beam, an operation is carried out, such as for instance a welding, a drilling, a cutting or a lighting operation, wherein the lasing gas which comes from the at least one lasing gas source is fed through at least one lasing gas filter before the gas is supplied to the laser source. The invention further relates to the use of a quick-change filter for cleaning gases consumed in laser processing apparatuses.

Abstract: An air-filter assembly is adapted to be used with a velocity stack of a carburetor of an internal-combustion engine of an automobile. The air-filter assembly includes a generally hollow air-filter member defining an open face, a closed face, and a side connected to and extending between the open and closed faces of the air-filter member. The closed face and side define an air-inlet end, an air-discharge end disposed opposite the air-inlet end, and an air filter arranged between the air-inlet and air-discharge ends. The air-inlet end is adapted to permit air to flow therethrough from exterior the air-filter assembly. The air filter is adapted to remove impurities entrained in the airflow and permit the filtered air to flow therethrough. The air-discharge end is adapted to permit the filtered air to flow therethrough into the velocity stack.

Abstract: A filter (8) for venting an enclosure (1) containing an electrical apparatus (4), such as a lens or lighting unit of a motor vehicle, and exposed to moisture or atmospheric agents, includes a tubular body (20) with a through cavity or conduit (11) opening at opposite ends (9, 10) of the body (20), which is coupled to a venting aperture (6) of the enclosure (1), the filter (8) including a hydrophobic filtering element; the body (20) of this filter (8) has at least two portions (20A, 20B) set at an angle to each other, the membrane filtering element (15) being in the interior of the body (20) and associated therewith so as to form one piece therewith, and being coupled to the body (20) in a manner transverse to an axis of at least one of the portions. The membrane is located within the mould before injection molding.

Abstract: A deflector for an aircraft engine comprises a screen attached to a base, a connector connecting the base and the engine, a mechanism to limit the movement of the connector and base, a spring that has two ends, one end being attached to the base inside surface, the spring extending past the base, and the spring's other end is positioned proximate the screen; and a shock absorbing means attached to the base, and connects the base with the engine, whereby when a foreign object contacts the deflector with a force sufficient force to move the spring and the shock absorbing means, the screen, the spring and the shock absorbing means are urged towards the engine, the movement of the screen and the spring being controlled by the shock absorbing means and the limiting mechanism, preventing the foreign object, such as a bird, from entering the engine.

Abstract: A smoke evacuating system for use during surgical procedures, particularly minimally invasive procedures involving the use of a laser or cautery at a surgical site having an associated higher than ambient pressure, wherein the system includes a filter with a site side and an outlet side and a fluid conduit extending between the surgical site and the filter. The filter includes a filter media and a housing substantially surrounding the filter media with a space between the filter media and the housing to collect condensed vapor. The filter exhibits low resistance or a low pressure drop and resists fluid flow, whereby the higher than ambient pressure is not substantially diminished and generates a fluid flow in the fluid flow path tending to carry smoke to and through the filter.

Abstract: Embodiments of the invention generally provide a containment system having integrated bubble tight-dampers. In another embodiment, the containment system includes an integral auto-scan mechanism disposed in the housing of the containment system so that a filter element, disposed in the housing, may be leak tested without accessing the interior of the housing. In yet another embodiment, a method for testing a filter disposed in a containment system includes challenging an upstream side of a filter element disposed in a housing of the containment system with a test aerosol, and automatically moving a probe disposed within the housing to obtain samples for leak testing.

Abstract: The present invention relates to an air filter unit (1) having the shape of a tube comprising a top plate (6), having an air inlet (7) leading into the interior of the tube, whereby the top plate (6) includes fasteners (13) for removably attaching said air filter unit to a wall (2) so that the air inlet of the top plate is concentrically disposed in relation to an opening in said wall, and a sealing ring (14,15) of a resilient material surrounding the air inlet in the top plate. According to the present invention, the top plate (6) includes at least one protrusion (16) on the side thereof facing said wall (2) in use, the height of said protrusion (16) being less than the distance with which the sealing ring (14,15), when not subjected to load, projects out from the surface of the top plate.

Abstract: An air-filtration system and method for removably attaching a filter element to portable air-circulation devices and building HVAC air-intakes. One such system provides a filter portion having a circular outer periphery, an inner periphery, a slit running from the outer periphery to the inner periphery that creates a first and second end of the filter portion, and a plurality of fastening mechanisms. One method includes manufacturing a plurality of air-permeable filter sheets, determining a shape of a portable electric fan that includes a fan cage, a support stand, and a motor casing, measuring a size of an inlet side of the fan cage and a size of the motor casing, cutting the plurality of filter sheets such that a plurality of filter portions are created, and attaching a plurality of fastening mechanisms to each one of the plurality of filter portions.

Abstract: A tamper resistant hydrocarbon trap and air filter assembly includes a cylindrical carbon trap filter extending from a sealed upstream end to a downstream end seated and sealed in a forwardly facing recess of an adaptor. A conventional cylindrical air filter surrounds the carbon trap filter with a sealed upstream end and a downstream end removable secured to an annular flange on the adaptor with the downstream end of the adaptor being arranged to be coupled to a vehicle's air intake.

Abstract: An in-line filter provided with a substantially elongated filter housing (1; 51) in which filtering material (A) is included, the filter housing being provided on a first end with an inflow opening (2) and, on a second, opposite end with an outflow opening (3), while at the inflow opening (2) and the outflow opening (3) fastening means (4-7) are provided for fastening a supply or discharge tube, respectively (8 or 9, respectively), while the fastening means (4-7) are quick-change couplings (4-7), a respective quick-change coupling (4, 5; 6, 7) having a coupled condition and an uncoupled condition, while in the quick-change coupling (4, 5; 6, 7) a shut-off valve (10) is provided which, in the coupled condition, assumes an open position thus allowing gas to pass and which, in an uncoupled condition, assumes a closed position thus not allowing gas to pass.

Abstract: A filter apparatus including a housing (2) and a filter insert (4), with an inlet opening formed on the housing (2) and an outlet fitting (6) mounted on a housing wall. The outlet fitting (6) has a contact face (7) for contact with the housing (2) and is provided with a tubular segment (13), which protrudes through an opening (9) of the housing, and a mounting element (22) is attached to the tubular segment (13) such that a region (10) of the housing (2) surrounding the opening (9) is clamped between the contact face (7) of the outlet fitting (6) and the mounting element (22).

Abstract: A filter for venting an enclosure (1) containing an electrical apparatus (4), such as a lens or lighting unit of a motor vehicle, and exposed to moisture or atmospheric agents, the filter including a tubular body (20) with a through cavity or conduit (11) opening at opposite ends (9, 10) of the body (20), which is coupled to a venting aperture (6) of the enclosure (1), the filter (8) including a hydrophobic filtering element; the body (20) of this filter (8) includes at least two portions (20A, 20B) set at an angle to each other, the membrane filtering element (15) being in the interior of the body (20) and being associated with it in such as manner as to form one piece therewith, and being coupled to the body (20) in a manner transverse to an axis of at least one of the portions.

Abstract: A hydrocarbon trap that includes a sheet paper element and a plurality of fingers. The paper element is at least partially formed of a material capable of adsorbing and desorbing gaseous hydrocarbons. The paper element is arranged into a plurality of adjacent sheet members. The fingers are disposed between and support adjacent pairs of the sheet members so that each adjacent pair of the sheet members forms a flow channel. A method for filtering gaseous hydrocarbons from an air flow is also provided.

Abstract: A biohazard safety enclosure or workstation particularly adapted for enclosing automated instrumentation includes a chamber defined by front, back, top, bottom, and opposed end walls; a HEPA filter across an air inlet opening into the chamber, and an airflow means to direct air horizontally through at least part of the chamber between the end walls. Preferably, the workstation has a second HEPA filter across an air outlet opening in the work chamber, with the airflow means including a conduit extending from the air outlet opening to the air inlet opening. A fan draws air through the conduit. All of the air can be exhausted from the workstation, or a part of the filtered air can be exhausted from the workstation and replenished through a make-up air inlet into the chamber.

Abstract: A maximum air flow, minimum space requirement household room air purifier comprising an enclosure arranged to stand on a room floor in a room corner formed by room walls and having a face opening toward the room, an arcuate air purifying HEPA filter, a motorized fan passing room air through said enclosure and said filter in room air purifying relation, and a filter unit comprising a frame carrying the filter for snug interfittment with the enclosure face opening. The filter frame is provided with a reversible self-latch for removably securing the filter to the face opening and a seal against unpurified air by-passing the filter.

Abstract: A ventilation system providing NBC protection for at least one closed security space and/or protection space with constant slight excess pressure, the ventilation system substantially having an air inlet and air outlet, an explosion protection valve, a prefilter, a filter for suspended matter, an activated carbon filter and an air conveying device for sucking in the air to be purified and for distributing the purified air, and wherein the ventilation system has at least one of the three following built-in elements: an explosion protection valve which is combined with and cooperates with the prefilter; a combined activated carbon filter made of activated carbon which is specifically effective against biological and/or chemical toxic substances, on the one hand and, on the other hand, against radionuclides; and an air pump configured as a double bellows.

Abstract: An air induction system for an engine to remove contaminants from intake air prior to delivery to the engine. The system includes a filtering unit having barrier filter panels attachable to a mounting frame. The filter panels are interchangeably usable. A juncture between first and second filter panels and the mounting frame is located at a region of relatively lower quantity of intake air flow. The juncture includes lugs on the filter panels which facilitate interchangeability. An opening above the filtering unit permits easy installation and removal of filter panels.

Abstract: A liquid trap device for gas includes a trap housing and a liquid filter disposed in the trap housing. The liquid filter includes an upper end wall having an opening communicating with a gas inlet, a lower end wall and a cylindrical filter element providing a connection between the upper end wall and the lower end wall. An inflow guide tube is disposed in the filter element, the inflow guide tube having a uniform path area and extending from the opening to the lower end wall so as to guide gas flowing into the gas inlet into the filter element. A distance between a lower end of the inflow guide tube and the lower end wall is set at 20 mm or less. Thus, the liquid trap device for gas has a high performance for trapping liquid.

Abstract: A detachable filtering apparatus for an air conditioning system and an installment method thereof provides an air disinfection function. It can be operated continuously, is suitable for conventional air conditioners and is applied at a place that requires disinfection. A hollow circular frame and a multi-aperture filter screen are detachably installed at a specified installation area of the air tube of the air conditioning system. The structure of the filtering apparatus can be installed easily and conveniently and is suitable for adjustable air pipes. It is convenient to maintain the air conditioner.

Abstract: A device and method for preventing ingression of contaminants and moisture and for removing moisture from a fluid reservoir, the device comprising a fluid reservoir for supporting a fluid therein, a fluid reservoir opening for allowing an exchanging of air between an interior of the fluid reservoir and the ambient surrounding, and a membrane-based reservoir dryer located in fluid communication with the fluid reservoir, the membrane-based reservoir dryer comprising a source of compressed gas and a membrane dryer for drying the compressed gas to increase the capacity of the compressed gas for absorbing moisture from the fluid in the reservoir.

Abstract: The invention relates to a filter element (50), in particular for a tank breather filter (10), the filter element (50) being produced from a flat filter material. To form the filter element (50) in such a way that it can be produced at low cost, it is proposed that it is made in one piece and has an end wall (51), which is surrounded by a corrugated side wall (52) aligned at an angle with respect to the end wall (51). A method for producing a filter element of this kind (50) and a tank breather filter (10) with a filter element of this kind (50) are also proposed.

Abstract: A vacuum cleaner includes a housing, a nozzle inlet, a suction generator and a dirt cup. The dirt cup includes a dirt collection chamber, an inlet and an open end. Additionally, the vacuum cleaner includes a filter assembly. The filter assembly includes a filter housing defining a filter chamber. The filter housing and chamber mate with the open end of the dirt cup. A filter element is held in the filter chamber on a ribbed support.

Abstract: The strainer comprises an unitary body having a main section and a collar section located around the main section. The collar section has a substantially outwardly-projecting portion located around the main section and an upstream projecting portion located around the substantially outwardly-projecting portion.

Abstract: A filter assembly having a filter media and adapted for use with a tube includes a filter housing adapted to contain the filter media therein. The filter housing includes a first nipple and a second nipple, at least one of which is adapted to engage with the tube. At least one engaging member is adapted to releasably engage with a corresponding engaging member of a manifold via a rotation of the filter housing from about 1° to about 180°.

Abstract: In a fan filter unit for filtering and continuously supplying clean air into a clean room, the fan filter unit includes a chemical filter for removing chemical contaminants contained in the air, a fan for sucking and blowing out the air, and a particle filter for removing particles such as dusts and moisture contained in the air. A filter medium of the chemical filter has a circular tube shape and is disposed between an inner circular tube and an outer circular tube. A cover is detachably combined with top portions of the inner and the outer circular tubes, and prevents air flow through the top portions of the inner and outer circular tubes. The air is sucked only through the outer circular tube, the chemical filter and the inner circular tube by a suction force of the fan. Accordingly, velocity distribution of the air passing through the chemical filter may be improved and lifetime of the chemical filter may be increased.

Abstract: A personal respiratory protection device 10 that comprises a mask body 12 that has a structure 35 located on it for receiving a clean air supply source such as a filter cartridge 14. The clean air receiving structure 35 has a first threaded portion 34. The clean air supply source has a second threaded portion 58 that has a thread 60 that mates with a thread 36 of the first threaded portion 34. The first and second threaded portions 34 and 58 engage each other at a high thread pitch and include an integral détente. A stop prevents over-rotation of the clean air supply source 14 relative to the mask body 12 during the securement operation. The inventive device allows the clean air supply source 14 to be attached to the mask body 12 with minimal rotation and is sufficiently intuitive that users may only need one hand to attach and replace the clean air source component 14 without having to remove the respirator 10 from their face.

Abstract: An operating room filter system connectable to a surgical body gas evacuator, such as a trocar, that includes a carbon monoxide filter media that removes carbon monoxide from a surgical waste gas. In addition, the inclusion of further filter media upstream of the carbon monoxide filter media inhibits the saturation of the carbon monoxide filter media to thereby provide an extended life to the filtration system.

Abstract: A blower has a carrying frame provided with a base plate. A fan with a fan housing is mounted on the carrying frame. The fan housing has an intake opening that faces the base plate and is spaced from the base plate. An intake gap is formed between the base plate and the fan housing. An internal combustion engine drives the fan in order to take in working air through the intake opening and to blow out the working air through a blower tube. A leaf shield for preventing leaves and debris from entering the fan housing is provided and covers the intake gap. The leaf shield is made of a foam material having coarse pores to allow unimpaired intake of the working air and to prevent leaves or other debris from adhering to the leaf shield.

Abstract: An air purifying device is provided for removing airborne particles. The device includes a housing including an air inlet and an air outlet. A fan is positioned within the housing for drawing air into the housing through the air inlet and expelling air through the air outlet. A filter assembly is positioned within the housing between the air inlet and the fan. The filter assembly includes a frame and a filter element mounted to the frame. The device also includes a hanger and an elongate hanger support that removably extends within the hanger. Either the hanger or the elongate hanger support is coupled to the frame while the other is coupled to the housing. The hanger can include a channel or a pair of opposed legs configured to form a gap.

Abstract: A method of providing a filter element with a thermoplastic material. The filter element is adapted for at least one of a group having filtering, conducting and influencing a medium. The thermoplastic material at least partly surrounds the filter element. The thermoplastic material is adapted for at least one of a group comprising coupling, connecting, sealing, fixing, adjusting, aligning, receiving, protecting, and positioning the filter element. The plastic material is at least partly plastified for attaching the plastic.

Abstract: A smoke evacuating system for use during surgical procedures, particularly minimally invasive procedures involving the use of a laser or cautery at a surgical site having an associated higher than ambient pressure, wherein the system includes a filter with a site side and an outlet side and a fluid conduit extending between the surgical site and the filter. The filter includes a filter media and a housing substantially surrounding the filter media with a space between the filter media and the housing to collect condensed vapor. The filter exhibits low resistance or a low pressure drop and resists fluid flow, whereby the higher than ambient pressure is not substantially diminished and generates a fluid flow in the fluid flow path tending to carry smoke to and through the filter.

Abstract: A dust collector with an invertible wind exhausting case includes a wind exhausting case having an upper and lower cover, which is respectively provided with two threaded holes of the same size in two lateral sidewalls. Two bolts combine tightly the lower cover with each of two upper horizontal tubes of two upper side frames of a platform truck, by screwing the threaded holes. The threaded holes of the upper cover are sealed up with bolts. In case the position of the fan motor and the sucking tube vase is needed to be inverted upside down, it is enough to screw loose the seal bolts of the platform truck and those of the upper cover and then the wind exhausting case can be inverted upside down and then seal bolts are screwed tight again. Thus the inverting work of the invention is much more simplified than a conventional one.

Abstract: An air induction system for an engine to remove contaminants from intake air prior to delivery to the engine. The system includes an assembly for filtering air which is mounted in advance of the engine, and a duct for delivering air from the assembly to the engine. A sealing system is provided which prevents entry of unfiltered air while simultaneously permitting movement of the engine relative to adjacent parts of the airframe as engine power setting varies. The seal is protected from high pressures in the duct which can occur in operation of the engine.

Abstract: A vertical-shaft air filtering device having high flow rate and two-way air intake structure includes an air filter having its annular filtering member provided thereon with a fixed annular cover which is provided with an auxiliary air intake and a sheet-shaped filtering member in the center. Thus, air sucked in a hollow tube can pass through the annular filtering member and the sheet-shaped filtering member and, after filtered, get in the engine room of a vehicle, not only having a function of air filtering, but also able to enable the engine to increase instant air intake speed and amount.

Abstract: A bracket system holds a filter(s) in quick-attach and quick-release fashion. Brackets are combined in modular fashion, with conduit between the brackets, to create a “bank” of filters easily changed in number, arrangement, and flow scheme. Top brackets and bottom brackets capture/support the top end and bottom end of a filter, respectively, and filter inlet and outlet ports preferably slide onto and off of cooperating tubes/ports in the bracket modules without tools or threaded connections. A retainer may pivot on and off of its respective filter, holding the filter in place and releasing the filter, respectively. After pivoting the retainer up from the filter, the filter may be lifted up off of its respective bottom module, so that the filter is substantially vertically and pivotally removable from the bracket system.

Abstract: The present invention relates to a dust and dirt collecting unit for a vacuum cleaner capable of simultaneously performing a primary cyclonic dust collection and a secondary filter dust collection. According to the present invention, there is provided a dust and dirt collecting unit for a vacuum cleaner, which is mounted to one side of a main body of the vacuum cleaner to filter sucked air containing foreign substances.

Abstract: A multi-spectral shield and associated inlet structure is provided for reducing the signature of an air inlet port defined within an exterior wall of an aircraft, ship, or land-based vehicle across radar and infrared wavelengths. The multi-spectral inlet shield includes a plate disposed in front of the air inlet port. The plate is sized to visibly eclipse the air inlet port, when viewed from a direction perpendicular to the plate. The plate is supported in this position by a plate mount or splitter that extends from within the air inlet port and attaches to the plate. A support may optionally combine with the splitter to support the plate in this position. Air passes behind the plate and into the air inlet port via a channel defined around at least a portion of the plate.

Abstract: A dual-stage vacuum cleaner filter with a pre-filtration cap having pre-filtering screens. A base with an aperture and a filter media strip pleated in the shape of a frustocone can be mounted within the dirt cup of a handheld vacuum. A circular, planar gas impermeable lid is sealingly fixed at the end of the filter media strip opposite the base. The cap is removably mounted to the base covering the filter media strip and lid. The cap has sidewall and endwall pre-filtering screens, and when the sidewall screens become loaded with debris, the endwall screen permits air to flow through a gap between the cap and the lid to the filter media strip.

Abstract: An air filter system for use by airline passengers on commercial airlines and the like. The housing is configured to clamp to the gasper air supply nozzle of the airliner. The housing is configured to direct air from the air supply nozzle through the filter medium. Thus, the present invention provides a filter which may easily be installed by an airline passenger so as to mitigate airborne contaminants from the air supply nozzle of the airliner. The air filter system provides a flow of comparatively clean air to the passenger and the flow of comparatively clean air directs undesirable airborne contaminants found within the passenger cabin of the airliner away from the passenger, thus forming a region of comparatively clean air generally around the passenger.

Abstract: An arrangement for separating a hydrophobic liquid phase from a gaseous stream includes a coalescer filter, a housing, a gas flow direction arrangement, and a liquid collection arrangement. The coalescer filter includes a non-woven media of fibers. The housing includes an interior having a gas flow inlet and a gas flow outlet. The liquid collection arrangement is positioned within the housing construction and is oriented for receiving liquid collected from the coalescer filter and drained therefrom. Methods for conducting the separations are also provided.

Abstract: A securing seat for holding filtering cylinder of a dust collector is disclosed. The securing seat includes a binding mount and a binding belt, and the middle section of the inner edge of the binding mount is protruded with an inverted L-shaped holding plate. The top face of the binding mount is an engaging slot for engagement with a filtering cylinder. The top edge and the bottom edge at the inner face of the binding mount and the holding plate are respectively formed into lid and fastening slot. The filtering cylinder is mounted to the engaging slot and the lid and the fastening slot are adhered to each other. Thus, the securing seat is provided with excellent air tightness and the securing seat is firmly secured, and the air suction of the dust collector is improved.

Abstract: A biological safety cabinet includes a work chamber having a contaminated air discharge opening, a fan enclosure above the work chamber, a conduit extending from the chamber air outlet to the top of the fan enclosure, a first HEPA filter in the top of the fan enclosure, a second HEPA filter between the fan enclosure and the work chamber, and a fan within the fan enclosure to convey air through the conduit from and the first HEPA filter into the fan enclosure, and to discharge air under positive pressure from the fan enclosure through the exhaust port and through the second HEPA filter into the work chamber. Due to the construction of the cabinet, the fan can be repaired or replaced without the need to observe biohazard procedures.

Abstract: Embodiments of a key system for filters and their connecting heads/holders are shown. The filter cartridge and its holder each have a keyed surface, one being a protruding “key” and one being a recessed “lock”. Cooperation of these keyed surfaces is required in order for the filter cartridge to be installed in the holder, so that mismatched cartridges cannot be installed into the holder, for example, to prevent a particular type of cartridge from being placed in a filtration or other process where it would be inappropriate, or undesired. The keyed surfaces are selectively locate-able preferably at different circumferential locations on a perimeter of the filter and a corresponding location on a perimeter of the head/holder. The perimeter may be, for example, on an outer shoulder surface of a filter and an inner surface of a valve head, or on outer and inner surfaces of connectors that provide a liquid seal between the filter and the head/holder.

Abstract: A cyclone-type dust-collecting apparatus for a vacuum cleaner comprises a conically shaped grill assembly disposed at the air outflow port of a cyclone body. The grill assembly includes a grill portion and prevents reverse flow of dust and dirt from the cyclone body. The grill assembly members are easily separable to allow a user to easily remove the dirt collected in the grill portion by simply separating the second grill member from the connection member and washing the second grill member with water.

Abstract: Disclosed are a vent disclosed for a septic system, including a conduit configured to vent gas therefrom, including a leg configured to conceal a portion of, and convey gas from, the conduit, and a method of concealing a conduit configured to vent gas from a septic system including sizing the conduit, then mounting on the conduit a leg configured to convey gas from the conduit.

Abstract: A filter element composed of a nonwoven filter web of metal fibers affixed to a support body, in which the metal fibers of the filter web form an unsintered composite having a porosity of at least 90%. Preferably the metal fibers have a diameter of at most 4 ?m.

Abstract: A device for filtering the intake air of an internal combustion engine having an expansion box (110) with an opening (12) for the intake air to pass therethrough, has a filter fixed to the opening that includes a first tubular filtering element having an upper annular element (1) having an upper end of the first tubular filtering element fixed thereto. A second filtering element is peripherally fixed to the upper annular element, over an upper end of the first tubular filtering element. A lower support (4) has an annular housing (9) for receiving the lower end of the first tubular filtering element therein, and a flat flange (7) for fixing the filter to the expansion box.

Abstract: An air filter for a well is installed within a well casing of the well. The air filter forming an airtight seal around the well casing of the well, such that all the air that enters and exits the well must pass through the air filter. The air filter preferably includes a filter housing, at least one removable gasket and a removable filter cartridge installed within an opening extending through the filter housing. The air filter prevents dirt, dust, bacteria, gaseous chemicals, volatile organic compounds, (VOCs), insects and other air born airborne contaminants from entering and possibly contaminating the well. An air filter may also be installed within a vent pipe extending through a well seal attached to the top of a well casing of a well.