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Title:
PERSONAL AIR FILTRATION DEVICE
Document Type and Number:
WIPO Patent Application WO/2016/018797
Kind Code:
A1
Abstract:
The present invention is a multi-inlet mouth-held filtration apparatus or face mask with a multi-stage filter, with each filter section optionally being individually replaceable to inexpensively filter out many different particulates, chemicals, or moisture depending on the specific environment. In some embodiments each section can be individually re laced for reduced cost.

Inventors:
MUNSTER JASON (US)
Application Number:
PCT/US2015/042211
Publication Date:
February 04, 2016
Filing Date:
July 27, 2015
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
MUNSTER JASON (US)
International Classes:
A61M16/06; A62B7/10; A62B9/06; A62B18/02
Domestic Patent References:
WO1988006468A11988-09-07
Foreign References:
US20070163588A12007-07-19
US20140045682A12014-02-13
US20060225738A12006-10-12
US20030234016A12003-12-25
Attorney, Agent or Firm:
KEOWN, Wayne (One Portland SquarePortland, ME, US)
Download PDF:
Claims:
What is claimed is:

1. A mouth-held multi -inlet air filter apparatus comprising a first tubular housing having a proximal end, a length and a distal end, wherein an indentation containing an elastomeric material is present at the proximal end to allow teeth to bite down on the apparatus and wherein a flanged and flexible mouthpiece is disposed distal to the indentation to allow lips of the mouth to form a seal with the apparatus, wherein a longitudinal channel is disposed within the housing, the channel being in fluid communication with the mouth and with a plurality of filter inlets, each filter inlet comprising an additional housing surrounding a channel having an identical replaceable filter disposed in an airtight manner therein, wherein each identical filter removes from air drawn through the filter in the filter channel and through the longitudinal channel into the mouth, one or more of PM2.5 particles, S02, N02, 03 and water vapor.

2. The air filter apparatus according to claim 1, further comprising straps to secure the apparatus to a user's head.

3. The air filter apparatus according to claim 1, wherein the distal end of the housing contains a replaceable one way check valve to allow easier exhalation and moisture management.

4. The air filter apparatus according to claim 1, wherein each replaceable filter is a multisection filter having different sections in series, wherein each section is a replaceable filter designed to filter a particular pollutant, and wherein different sections filter different pollutants.

5. The air filter apparatus according to claim 4, wherein each filter section is surrounded by an outer shell, and wherein the outer shells of a proximal section and a distal section are surrounded by O-rings, to provide an airtight seal between the filter section and the inlet housing.

6. The air filter apparatus according to claim 4, wherein the proximal edge of the proximal filter section has a complementary shape to a shape in the housing, whereby the proximal filter section locks into the inlet housing, and wherein adjacent filter sections lock together via complementary shaped edges, elastomeric edges, or both.

7. The air filter apparatus according to claim 4, wherein at least one filter section is a PM2.5 filter and at least one filter section filters S02 and N02, 03, or water vapor.

8. The air filter apparatus according to claim 7, wherein one filter section is a PM2.5 filter, one filter section is an S02 and N02 filter and one filter section is an O3 filter.

9. The air filter apparatus according to claim 4, wherein at least one edge of each filter section is in operable contact with a pressure monitor to indicate when the filter section is becoming clogged and needs to be replaced.

10. The air filter apparatus according to claim 1, wherein each replaceable filter filters water vapor.

11. The air filter apparatus according to claim 1 , wherein each replaceable filter is a multistage filter with several different filters being combined into a single section.

12. The air filter apparatus according to claim 11, wherein at least one filter is a PM2.5 filter and at least one filter filters S02 and N02, or O3.

13. The air filter apparatus according to claim 1 , further comprising an indicator to indicate levels of pollution.

14. The air filter apparatus according to claim 13, wherein the indicator is selected from a multi-color LED light and an LCD display.

15. The air filter apparatus according to claim 1, further comprising a wireless communicator and power source.

16. The air filter apparatus according to claim 3, wherein the replaceable one way check valve is operably connected to a turbine and a capacitor, whereby air flowing through the check valve powers the turbine to charge the capacitor.

17. The air filter apparatus according to claim 1 or 4, wherein each filter or filter section has a color band associated with the strength of the filter, the color also being associated with an Air Quality Indicator in the country of sale or use.

18. A replaceable filter for an air filter apparatus, wherein the replaceable filter is a multisection filter having different sections in series, wherein each section is a replaceable filter designed to filter a particular pollutant, and wherein different sections filter different pollutants.

19. The replaceable filter according to claim 18, wherein each filter section is surrounded by an outer shell, and wherein the outer shells of a proximal section and a distal section are surrounded by O-rings.

20. The replaceable filter according to claim 18, wherein the proximal edge of the proximal filter section has a complementary shape to a shape in a housing in the air filter apparatus, whereby the proximal filter section locks into the housing, and wherein adjacent filter sections lock together via complementary shaped edges, elastomeric edges, or both.

21. The replaceable filter according to claim 18, wherein at least one filter section is a PM2.5 filter and at least one filter section filters S02 and N02, or 03.

22. The replaceable filter according to claim 21, wherein one filter section is a PM2.5 filter, one filter section is an S02 and N02 filter and one filter section is an O3 filter.

23. The replaceable filter according to claim 18, wherein at least one edge of each filter section is in operable contact with a pressure monitor to indicate when the filter section is becoming clogged and needs to be replaced.

24. The replaceable filter according to claim 18, wherein the air filter apparatus is a mouth- held multi -inlet air filter apparatus.

25. The replaceable filter according to claim 18, wherein each filter section has a color band associated with the strength of the filter, the color also being associated with an Air Quality Indicator in the country of sale or use.

26. A body for a mouth-held multi-inlet air filter apparatus comprising a first housing having a proximal end, a length and a distal end, a longitudinal channel being disposed within the housing, the channel being in fluid communication with the mouth and with a plurality of inlets, each inlet comprising an additional housing surrounding a channel configured to hold a replaceable filter in an airtight manner therein, such that each filter can independently remove from air drawn through the filter in the filter channel and through the longitudinal channel into the mouth, one or more air pollutant.

27. The body for a mouth-held multi-inlet air filter apparatus according to claim 26, wherein the first housing is of a tubular shape, wherein an indentation containing an elastomeric material is present at the proximal end to allow teeth to bite down on the apparatus and wherein a flanged and flexible mouthpiece is disposed distal to the indentation to allow lips of the mouth to form a seal with the apparatus.

28. The body for a mouth-held multi-inlet air filter apparatus according to claim 26, further comprising straps to secure the apparatus to a wearer's head.

29. The body for a mouth-held multi-inlet air filter apparatus according to claim 26, wherein the distal end of the housing contains a replaceable one way check valve to allow easier exhalation and moisture management.

30. The body for a mouth-held multi-inlet air filter apparatus according to claim 29, wherein the replaceable one way check valve is operably connected to a turbine and a capacitor, whereby air flowing through the check valve powers the turbine to charge the capacitor.

31. The body for a mouth-held multi-inlet air filter apparatus according to claim 26, further comprising an indicator to indicate levels of pollution.

32. The body for a mouth-held multi-inlet air filter apparatus according to claim 26, wherein the indicator is selected from a multi-color LED light and an LCD display.

33. The body for a multi-inlet mouth held air filter apparatus according to claim 26, further comprising a wireless communicator and power source.

34. A mask air filtration apparatus comprising a mask with an elastomeric face edge to form a seal with a face, a one-way exhalation check valve, straps to hold the mask in place, a plurality of filter insertion apertures and, disposed within the filter insertion apertures in an airtight manner, identical multi-stage filters according to claim 18, 19, 20, 21 , 22, 23, 24 or 25.

35. The mask air filtration apparatus according to claim 34, further comprising an LCD or LED display to indicate levels of pollution.

36. The mask air filtration apparatus according to claim 34, further comprising a wireless communicator and power source that communicates with one or more of external sensors, computers, other wireless devices, or handheld or worn electronic devices, to receive or send information related to pollution, use of the apparatus, or health information.

37. The mask air filtration apparatus according to claim 34, further comprising a sensor to measure pollution levels.

38. An air filtration enclosure device comprising a plastic cover held in place by support ribs to maintain an enclosed space, an elastomeric sealing edge, a zipper embedded in an elastomeric material to allow access to the enclosed space and, embedded within the plastic cover a solid plastic piece containing a plurality of filter insertion apertures and, disposed within the filter insertion apertures in an airtight manner, identical multi-stage filters according to claim 18, 19, 20, 21, 22, 23, 24 or 25.

39. The air filtration enclosure device according to claim 34, further comprising a sensor to measure levels of pollution.

40. The air filtration enclosure device according to claim 35, further comprising a wireless communicator and power source that communicates with one or more of external sensors, computers, other wireless devices, or handheld or worn electronic devices, to receive or send information related to pollution, use of the apparatus, or health information.

41. The air filter apparatus according to claim 1, wherein the S02 and N02 filter comprises one or more of activated carbon, pitch carbon, and PAN carbon.

42. The air filter apparatus according to claim 41, wherein the one or more of activated carbon, pitch carbon, and PAN carbon is augmented by one or more of iron (Fe), copper (Cu), vanadium (V), or titanium dioxide (Ti02) nanoparticles.

43. The replaceable filter according to claim 21, wherein the S02 and N02 filter comprises one or more of activated carbon and pitch carbon.

44. The replaceable filter according to claim 43, wherein the one or more of activated carbon, pitch carbon, and PAN carbon is augmented by one or more of iron (Fe), copper (Cu), vanadium (V), or titanium dioxide (Ti02) nanoparticles.

45. An air filter comprising of one or more of pitch carbon and PAN carbon.

46. The air filter according to claim 45, wherein the pitch/PAN carbon is augmented by one or more of iron (Fe), copper (Cu), vanadium (V), or titanium dioxide (Ti02) nanoparticles.

47. The air filtration enclosure device according to claim 35, conformed to fit over a stroller, baby carrier or other furniture.

48. A stroller, baby carrier or other furniture comprising the air filtration enclosure device according to claim 35.

49. The air filtration enclosure device according to claim 35, 47, or 48, further comprising a pneumatic pump to force air through the air filter.

Description:
PERSONAL AIR FILTRATION DEVICE

BACKGROUND OF THE INVENTION

Field of the invention

The present invention is in the technical field of air filtration. More particularly, the present invention is in the technical field of personal portable air filtration.

Summary of the related art

Over 2 billion people worldwide live in hazardous air pollution. Current filters are either stationary room filtration apparatuses that are not portable, and thus of little use outdoors in polluted areas, or masks. Current masks only filter PM2.5, one of the three major life-threatening common air pollutants, and are very costly and out of the price range of those most affected by air pollution. Moreover, the only commercial masks capable of effectively filtering S0 2 and N0 2 , the two remaining deadly air pollutants, are full-face gas masks with large chemical-based scrubbers that are expensive and uncomfortable. This renders current affordable masks only able to filter out PM2.5, leaving them incapable of filtering other major pollutants that are proven to cause health issues and early death. Further, many masks do not get an effective seal against the face, allowing outside air to pass around the filter and instead go through the leaks. Further, nearly all solutions require sufficient design and material to make them not cost-effective for most of the world's citizens. US Patent No. 6752149 discloses a nasal air filter with replaceable filters which must form a tight seal on the face around the nose. There is, therefore, a need for inexpensive personal air filters that can form a good seal with the mouth and filter out a variety of air pollutants.

BRIEF SUMMARY OF THE INVENTION

The present invention is a multi-inlet mouth-held filtration apparatus or face mask with a multi-stage filter, with each filter section optionally being individually replaceable to inexpensively filter out many different particulates, chemicals, or moisture depending on the specific environment.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a top view of an embodiment of a multi-inlet filtration apparatus of the present invention.

Fig. 2 is a perspective view of an embodiment of a of the multi-inlet filtration apparatus of the present invention.

Fig. 3 is a perspective view of an embodiment of a multi-stage filter of the present invention. Fig. 4 is an exploded view of an embodiment of a multi-stage filter of the present invention. Fig. 5 is a perspective view of an embodiment of a mask filtration apparatus of the present invention.

Fig. 6 is a perspective view of an embodiment of a dome-shaped canopy for use with the filtration device.

Fig. 7 is top view of an embodiment of a dome-shaped canopy for use with the filtration device. Fig. 8 is a perspective view of an embodiment of a dome-shaped canopy for use with the filtration design for use over a baby stroller, crib, or other infant resting or play place.

Fig. 9 is an exploded view of a replaceable one-way valve with an optional power turbine for the present invention.

Fig.10 shows filtration efficiency results for a PM2.5 multi-layered polyester filter.

Fig. 11 shows filtration efficiency results for a single -ply S02 unmodified pitch based carbon fiber filter.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the invention in more detail, in Fig. 1 (top perspective) and Fig. 2 (front end perspective), there is shown a multi-inlet mouth held filter apparatus 1, with a tubular housing for connection to the mouth and additional housings as filter inlets. While shown here as a two-inlet filter apparatus, the design is not limited to only two inlets, and other designs with more inlets can be used to allow for less conductance loss of airflow and thus easier breathing. The multi-inlet filter apparatus 1 has an optional replaceable one-way valve, also called a check valve, 2 for easier exhalation and moisture management, insertion slots 3 for filters, a flanged mouthpiece 4, made of rubber or other elastomeric material, to provide a seal against the environment using one's lips, with optional straps 5 to hold the filter apparatus to the face and a rubber (or other reversibly compressible material) indented section 6 to comfortably bite down on the filter apparatus to further hold the filter apparatus in place. Compared to current respirators which use the entire mask as a filter, the multi-inlet filter 1 reduces filter material area to reduce cost of the filtration apparatus while simplifying a proper seal by using the flexible mouthpiece 4, together increasing cost efficacy of the filter apparatus. An optional indicator 7 is either a multi-color LED light to indicate levels of pollution and required filter, or an LCD display to transmit information. An optional wireless communicator and power source 8

communicates with, without limitation, external sensors, computers, other wireless devices, or handheld or worn electronic devices, to receive or send information related to pollution, use of the apparatus, or potential health information.

In further detail, still referring to Fig. 1 and Fig. 2, the multi-inlet filter 1 can be made of plastic, rubber, metal, or other rigid or semi-rigid polymers. The mouthpiece 4 is held between the lips to ensure a seal so that air can only travel through the filters. The distance from the reversibly compressible indented section 6 to the flexible mouthpiece 4 is sufficient to allow varying clearances between the indented section 6 and mouthpiece 4. The size of flexible mouthpiece 4 varies based on the size of the user. The length of the filter apparatus from the rubber mouthpiece 4 to the filter insertion slots 3 is sufficient to allow small clearance from the lips to filter insertion slots 3. The length of the filter insertion slots 3 vary to fit the filters, based on the intended use of the filtration apparatus. The optional wireless communicator and power source 8 sends and receives information to and from a plurality of other devices and sources, including, without limitation, a central database that stores anonymous information about pollution in different locations and filter use, a smart phone, or any other external device. An indicator 7, with an LED for low-cost apparatuses, and an LCD for higher-cost apparatuses, receives information from the wireless communicator or an internal information source to indicate the type and level of filters necessary for ambient pollution, and when filters need replacement. The location of indicator 7 and wireless communicator and power source 8 is not fixed, but could be anywhere on the filter apparatus, including inside the apparatus.

Referring now to Fig. 3 and Fig. 4, the multi-section replaceable filter 9 has multiple sections 10, 11, and 12 (or more or less, depending on the application; while three sections are used in this diagram, any number of sections can be brought together). Each filter section can house a separate filter type designed to filter different compounds or chemicals (air pollutants). Each filter section has a plastic, polymer, or metal outer shell 13 with a filter held inside, and each section filters different physical or chemical species. Each section can be individually replaced to tailor the multi-stage filter to the environment to reduce cost of the filter apparatus. For example, in an environment where filter section 10 is used frequently, but filter section 11 is rarely necessary, replacing filter section 10 when it expires, rather than replacing an entire filter apparatus, results in significant cost savings for the user. Filter sections lock together with complementary shaped edges 14. Complementary shaped edges 14 can be either the filter section housing or have rubber edges to ensure seal between filter sections. Filter sections at the ends of the filter have O-rings 15, on the outside to ensure that ambient air goes through the filter and not around it. In some embodiments, between each filter section is an optional pressure monitor to indicate when a filter is becoming clogged and needs replacement. The first filter in the series locks into the housing with a specific matching locking design built into the first filter and into the filter inlet housing of the filter apparatus. The filter(s) after the first filter lock(s) to the first filter, (or subsequent filters) and thus is or are also held in place by the lock between the first filter and the filter apparatus.

In an alternative embodiment, the filter 9 is multi-stage with several different filters, all of the filters being combined into a single section for ease of use if a user prefers not swapping individual sections.

In some embodiments, still referring to Fig. 3 and Fig. 4, the filter arrangement comprises, without limitation, one section with a microfiber filter, polyester filter, or other filter type to filter out PM2.5, which is particulate matter smaller than 2.5 microns produced by power plants and known to be carcinogenic, another section with an activated carbon fiber filter to filter ozone, which is a byproduct of power production and combustion engines, known to be a health hazard, and another section with pitch-activated carbon fibers to filter out N0 2 and S0 2 , which are byproducts of power production and some combustion engines, known to cause long-term lung damage and asthma.

The PM2.5 filter, common to other respirators, differs in design in that this design of a long filter allows for a filter between 3 -35mm thickness, rather than the current thin filters, allowing the use of lower-cost materials to provide increased efficiency per unit cost.

Additionally, the use of a graded particulate filter, with a coarse outer filter for larger particulates and a fine filter for PM2.5 allows more efficient filtering.

The S0 2 and N0 2 filter differs from other chemical filters in that it uses pitch-carbon or chemically enhanced activated carbon as the filter medium,. Current carbon fiber filters are made from charcoal. Pitch carbon and polyacrylonitrile carbon (PAN-carbon), made from coal pitch, petroleum pitch, or tar pitch, is currently not used for filters, and, due it its expense, is used almost exclusively as a component for composites in airplane construction. The chemical properties of pitch/PAN carbon provide nearly double the adsorption surface area compared to standard activated carbon filters, and also have nitrogen inclusions which chemically enhance the catalyses and subsequent breakdown of S0 2 and N0 2 . Another embodiment of this filter is a chemically enhanced activated carbon or pitch/PAN carbon fiber. Currently no pollution mask uses chemically enhanced carbon fibers to enhance filtration and reduce pressure drop for a given filtration efficacy. The filter according to the invention optionally has activated carbon or pitch carbon augmented with, without limitation, one or more of iron (Fe), copper (Cu), vanadium (V), or titanium dioxide (Ti0 2 ) nanoparticles, as these elements attract S0 2 and N0 2 , to chemically enhance filtration. These particles catalytically alter S0 2 and N0 2 to forms that are more readily sequestered in the filter. These can allow for a thinner filter for a given efficacy, reducing how much the filters restrict breathing.

All of the above described filter sections are removable if they are unnecessary for certain environments, or additional sections are added for more types of pollutants. Air flows through filter sections from first filter to last filter, which progressively scrubs harmful physical and chemical species (pollutants) and/or moisture from ambient air. Each type of filter is available in several grades of efficacy, allowing users to use less expensive and less restrictive filter grades when more expensive ones are not necessary. Each type of filter section is optionally available with differing colors and print to indicate the compounds or chemicals filtered, as well as the efficacy level of the replaceable filter section. Filter lengths may also vary by the substance filtered to further distinguish type of filtration. Each filter optionally has a color band associated with the strength of the filter, the color also being associated with the Air Quality Indicator in the country of sale or use, providing a user with a simple metric to understand which level of filter is needed.

In some embodiments, for humid environments, a replaceable dessicant filter or filter section can be used in place of the air pollutant filters discussed above to remove all humidity from the air. The dessicant filter has simple screens to hold in the dessicant material. This will be of benefit to anyone suffering lung maladies exacerbated by moist environments, or to someone acclimated to a dry environment who is traveling to a humid environment. Since airborne viruses and bacteria and bacteria that cause illnesses such as Middle East Respiratory Syndrome (MERS) travel in water droplets, the dessicant filter can also be used to protect the user from these pathogens.

In some embodiments, still referring to Fig. 3 and Fig. 4, a replaceable filter 9 can optionally be made out of a material that can withstand high temperatures, including, without limitation, iron, steel, aluminum, tungsten, or titanium, allowing adsorbed impurities or other filtered chemicals and compounds to be burnt off by heating, without destroying the filter or filter material, thus allowing for re-use and recycling of a filter.

Referring now to Fig. 1 through Fig. 4, a multi-stage filter 9 is inserted into filter insertion slots 3 (channels in the filter inlet housings, which are in fluid communication with the longitudinal channel in the first housing) on the filter apparatus 1. The filter 9 can be removed and taken apart to replace separate filter sections and reassembled and re -inserted into filter insertion slots 3.

In some embodiments, referring now to Fig. 3 and Fig 5, a mask air filtration apparatus la is used with the replaceable multi-stage filter 9. The mask air filtration apparatus la can be made from, without limitation, plastic, other polymers, metals, and other materials, with the material at the face edge of the mask being elastomeric, such that it can form to a face and create a good seal against the environment. Mask filtration apparatus la has an optional or replaceable one-way exhalation valve 2 to ease exhalation and reduce moisture buildup in the mask. A replaceable multi-stage filter 9 is inserted into filter insertion apertures or slots 3. The mask is held in place with straps 5. In some embodiments, an optional LED or LCD display 7 is either a multi-color LED light to indicate levels of pollution and required filter, or an LCD display to transmit information. In some embodiments, an optional wireless communicator and power source 8 communicates with, without limitation, external sensors, computers, other wireless devices, or handheld or worn electronic devices, to receive or send information related to pollution, use of the apparatus, or potential health information. In some embodiments, the mask air filtration apparatus further comprises a sensor to measure the pollution level (not shown). The location of LED or LCD 7, the wireless communicator and power source 8, and the pollution level sensor is not fixed, but can be anywhere on the mask, including inside the mask.

In some embodiments, referring now to Fig.3, Fig. 6, Fig. 7, and Fig. 8, a plastic dome, or other-shaped enclosure, 16 can be used with the multi-stage filter 9 to create a clean enclosed environment. A clear plastic cover 17 has support ribs 18 to maintain a dome or other enclosed shape. At the bottom of the plastic cover 17 is an elastomeric piece 19. The elastomeric piece 19 conforms to an object, including, without limitation, cribs, beds, baby strollers, or other furniture, and create a sealed volume. The sealed environment and is easily accessible through zipper 20. The zipper 20 has a strip of rubber or another elastomeric material beneath it to further ensure environmental seal. A solid plastic piece 21 embedded on the clear plastic cover 17 houses filter insertion slots 3, and the multi-stage replaceable filter 9 is inserted into the filter insertion slots 3. In some embodiments, solid plastic piece 21 contains a pneumatic pump to force air through the filters, providing an active filter to the filtered environment and ensuring the occupant has a steady supply of fresh air, and providing positive pressure to ensure that polluted air cannot flow back through any leaks in the seal between the enclosure and the furniture. The enclosure can either be form-fitted and included in the manufacture of the stroller, crib, or other furniture, or it can be added separately.

In some embodiments, referring now to Fig. 9, a replaceable one-way valve system 2 has a one-way valve 22 which opens during exhalation to allow easier exhalation and venting of moisture, and closes during inhalation to prevent polluted ambient air from bypassing the filters. For more advanced filter apparatus embodiments, the one-way valve has turbine 23 which turns as air passes it, turning turbine stem 24, generating and storing electricity in turbine generator and capacitor 25. Electricity generated and stored in turbine generator and capacitor 25 can be used to power accessories on or associated with the filter apparatuses.

Among the advantages of the present invention is that it is portable, less expensive to manufacture and buy, less expensive to maintain than current filters, and more effective than most filters in filtering out more harmful species. The small design and materials chosen reduces the cost of the filter apparatus. The embodiments in which the multi-stage filter has each section being replaceable drastically reduces the cost of replacing filters by allowing the user to replace individual sections, rather than an entire filter. For portable filters, the filter apparatus and filter cost less to maintain than most filters in that only the filter is replaced, not the entire mask. The mouth-held filter apparatus is more effective in that the multi-inlet filter apparatus guarantees a complete seal compared to difficult-to-seal masks, since there is no mask edge inconformity to break the seal, forcing air to go through the filter and ensuring breathing of filtered air. The filter is more effective than nearly all other filters in that it filters particulate matter and in some embodiments chemical compounds and/or moisture, rather than just particulate matter. In preferred embodiments, the present invention is a personal filtration apparatus to filter out particulate matter and chemicals.

The following Examples are provided to further illustrate certain preferred embodiments of the invention and are not to be construed to limit the scope of the invention.

Example 1

Efficacy of a PM2.5 filter

Referring to Fig. 3 and Fig. 4, in some embodiments, one of the replaceable filters 10, 11, and 12 will be a particulate matter filter, and another will be an S0 2 and N0 2 filter. In an embodiment of the invention, a PM2.5 particulate matter multi-layered polyester filter, with a first course layer for larger particles, and a fine layer with a Minimum Efficiency Reported Value (MERV) rating of 13 (out of 20) was used. The layers were stacked by gluing with a fine glue that does not block air flow. This filter showed a 90% efficacy of filtering harmful particulate matter. Dylos particle counters were used to determine particle matter pollution levels before and after the filter. Particulate matter pollution was measured simultaneously before and after the filter with two calibrated particle counters. The difference in particles counted indicates the efficacy of the filter. Shown in Fig. 10 are the results of the test, indicating a nearly 90% effective filtration of PM2.5 Example 2

Efficacy of an SO? pitch carbon fiber filter

Still referring to Fig. 3 and Fig. 4, and multi-part filters 10, 11, and 12, S0 2 filtration was tested using a single ply of unmodified pitch-based carbon fibers as a filter medium. Pitch based carbon is made from hydrocarbon pitch, rather than the activated charcoal typically used for activated carbon fibers for filtration. The filters in this trial averaged 9mm in length and were woven into a fine mesh. The data were obtained using two Aeroqual ENV500 S0 2 detectors to determine S0 2 pollution levels before and after the pitch-based carbon filter. S0 2 pollution was measured simultaneously before and after the filter with the S0 2 detectors. The difference in S0 2 pollution levels indicate the efficacy of the filter. Shown in Fig. 11 are the results of the test, indicating a 15% effective filtration of S0 2 .

While the foregoing written description of the invention enables one of ordinary skill to make and use what is considered presently to be the best mode thereof, those of ordinary skill will understand and appreciate the existence of variations, combinations, and equivalents of the specific embodiment, method, and examples herein. The invention should therefore not be limited by the above described embodiment, method, and examples, but by all embodiments and methods within the scope and spirit of the invention as claimed.