U.S. patent application number 16/852993 was filed with the patent office on 2020-11-19 for reusable respiratory protection device.
The applicant listed for this patent is Applied Research Associates, Inc.. Invention is credited to Johnnie H. Copley, Christopher G. Estkowski, Delbert A. Harnish, Brian K. Heimbuch, Geoffrey A. Kibble, Sheila J. Nogueira-Prewitt, Thomas B. Stephenson, Chris Ward, Graham Wilson.
Application Number | 20200360645 16/852993 |
Document ID | / |
Family ID | 1000005192141 |
Filed Date | 2020-11-19 |
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United States Patent
Application |
20200360645 |
Kind Code |
A1 |
Heimbuch; Brian K. ; et
al. |
November 19, 2020 |
REUSABLE RESPIRATORY PROTECTION DEVICE
Abstract
A reusable respirator including a mask adapted for covering and
conforming to the face around the nose and a mouth of a user, a
strap configured to secure the mask to a face of the user, and a
filter component. All components of the respirator are capable of
being cleaned, disinfected and sterilized at temperatures in excess
of 50.degree. C. An outer surface of the mask is substantially
smooth and wettable for easily disinfecting and is shaped with a
pair of outer shield portions for housing particulate air filters.
The outer shield portions each include a closeable vent through the
outer surface that is adapted to provide a user seal check and
direct air flow through the outer surface for filtering by the
respective particulate air filter, which is adapted to filter at
least 95% of airborne particles.
Inventors: |
Heimbuch; Brian K.;
(Albuquerque, NM) ; Harnish; Delbert A.;
(Albuquerque, NM) ; Kibble; Geoffrey A.;
(Albuquerque, NM) ; Stephenson; Thomas B.;
(Albuquerque, NM) ; Nogueira-Prewitt; Sheila J.;
(Albuquerque, NM) ; Estkowski; Christopher G.;
(Pullman, MI) ; Copley; Johnnie H.; (Minooka,
IL) ; Wilson; Graham; (Flint, GB) ; Ward;
Chris; (St. Asaph, GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Applied Research Associates, Inc. |
Albuquerque |
NM |
US |
|
|
Family ID: |
1000005192141 |
Appl. No.: |
16/852993 |
Filed: |
April 20, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62848341 |
May 15, 2019 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61M 16/0605 20140204;
A61L 2202/22 20130101; A61M 16/1065 20140204; A61M 16/0683
20130101; A61M 2202/203 20130101; A61L 2/0035 20130101; A61L 2/206
20130101; A61M 2202/206 20130101; A61M 2209/088 20130101 |
International
Class: |
A61M 16/10 20060101
A61M016/10; A61M 16/06 20060101 A61M016/06; A61L 2/20 20060101
A61L002/20; A61L 2/00 20060101 A61L002/00 |
Goverment Interests
STATEMENT OF FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] This invention was made with government support under
Contract No. HHSO100201700032C awarded by the Department of Health
and Human Services, Office of the Assistant Secretary for
Preparedness and Response, Biomedical Advanced Research and
Development Authority. The government has certain rights in the
invention.
Claims
1. A reusable respiratory protection device, comprising: a mask
adapted for covering a portion of a user's face, said mask
comprising: a face seal adapted to conform to a user's face around
a nose and a mouth of the user; an outer surface; at least one
outer shield portion formed in the outer surface; and at least one
closeable deformable vent through the at least one outer shield
portion; at least one particulate air filter adapted to filter at
least 95% of airborne particles, said at least one particulate air
filter housed within the at least one outer shield portion, wherein
the at least one closeable deformable vent is adapted to direct air
flow through the outer surface for filtering by the at least one
particulate air filter, wherein the outer surface is substantially
smooth to mitigate bioburden accumulation and wettable to allow for
cleaning, disinfection, or sterilization thereof; and a strap
configured to secure the mask to the user's face.
2. The reusable respiratory protection device of claim 1, wherein
the device is configured to be cleaned, disinfected, and sterilized
without disassembly to facilitate reuse.
3. The reusable respiratory protection device of claim 2, wherein
the device is further configured to be sterilized by autoclaving,
gamma irradiation, vaporized hydrogen peroxide, or ethylene
oxide.
4. The reusable respiratory protection device of claim 1, wherein
the device is configured to be cleaned, disinfected, or sterilized
at temperatures above about 50.degree. C. to facilitate reuse.
5. The reusable respiratory protection device of claim 1, wherein
the mask is a unitary structure formed of a single piece of
material.
6. The reusable respiratory protection device of claim 1, further
comprising a protective pocket formed in each of the at least one
outer shield portion, the protective pocket being adapted to
protect the at least one particulate air filter, thereby permitting
cleaning and disinfecting of the outer surface.
7. The reusable respiratory protection device of claim 1, wherein
the strap and the mask are made of a silicone material that is
configured to be cleaned, disinfected, and sterilized to facilitate
reuse.
8. The reusable respiratory protection device of claim 1, wherein
the at least one particulate air filter comprises a filter media
having at least one polytetrafluoroethylene-based layer that is
wettable and sterilizable.
9. The reusable respiratory protection device of claim 1, where the
at least one outer shield portion is deformable for enabling
closure of the at least one closeable deformable vent for
functional testing of the face seal during use.
10. The reusable respiratory protection device of claim 1, wherein
the at least one outer shield portion forms a gap between the outer
surface of the mask and the at least one particulate air filter
that extends to the at least one closeable deformable vent, the gap
being adapted to provide ample space for dispersing flow of air
evenly across the surface of the at least one particulate air
filter.
11. The reusable respiratory protection device of claim 1, further
comprising an inner flexible layer disposed on an inner surface of
the at least one particulate air filter, wherein the inner flexible
layer is located between the at least one particulate air filter
and the user during use.
12. The reusable respiratory protection device of claim 1, further
comprising an identification tag, said identification tag being
adapted for scanning with a scanning device.
13. The reusable respiratory protection device of claim 1, wherein
the substantially smooth outer surface is configured to allow
cleaning or disinfecting of the device while being worn by the
user.
14. The reusable respiratory protection device of claim 1, wherein
the mask has no exhalation valve such that the device is configured
to maintain a sterile field in an environment surrounding the user
during use.
15. A reusable respirator, comprising: a unitary mask formed of a
single piece of material adapted for covering a portion of a user's
face, the mask comprising: a face seal adapted to conform to a
user's face around a nose and a mouth of the user; an outer
surface; a first outer shield portion formed in the outer surface;
a first deformable vent through the first outer shield portion; a
second outer shield portion formed in the outer surface; and a
second deformable vent through the second outer shield portion; a
first particulate air filter adapted to filter at least 95% of
airborne particles, said first particulate air filter housed within
the first outer shield portion; and a second particulate air filter
adapted to filter at least 95% of airborne particles, said second
particulate air filter housed within the second outer shield
portion, wherein the first deformable vent and the second
deformable vent are each adapted to direct air flow to the first
particulate air filter and the second particulate air filter,
respectively, wherein the outer surface of the mask is
substantially smooth to mitigate bioburden accumulation and
wettable to allow for cleaning, disinfection, or sterilization
thereof.
16. The reusable respirator of claim 15, wherein the first outer
shield portion is deformable for enabling closure of the first
deformable vent, and the second outer shield portion is deformable
for enabling closure of the second deformable vent, such that the
first deformable vent and the second deformable vent are
temporarily closeable for functional testing of the face seal
during use.
17. A method for processing a respirator for reuse, comprising: a)
providing a reusable respirator, comprising: a mask adapted for
covering a portion of a user's face, said mask comprising: a face
seal adapted to conform to a user's face around a nose and a mouth
of the user; an outer surface; at least one outer shield portion
formed in the outer surface; and at least one closeable deformable
vent through the at least one outer shield portion; at least one
particulate air filter adapted to filter at least 95% of airborne
particles, said at least one particulate air filter housed within
the at least one outer shield portion, wherein the at least one
closeable deformable vent is adapted to direct air flow through the
outer surface for filtering by the at least one particulate air
filter, wherein the outer surface is substantially smooth and
wettable to allow for disinfection thereof; and a strap configured
to secure the mask to the user's face; b) using the reusable
respirator in a field; and c) performing an extended reprocessing
protocol.
18. The method for processing a respirator of claim 17, further
comprising the steps of: performing a quick field reprocessing
protocol a predetermined number of times before step c).
19. The method for processing a respirator of claim 17, wherein the
respirator further comprises an identification tag, the method
further comprising: scanning the identification tag to track use of
the respirator, processing of the respirator, or both.
20. The method for processing a respirator of claim 17, wherein
performing the extended reprocessing protocol comprises sterilizing
the reusable respirator without disassembly.
Description
RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application No. 62/848,341, entitled "Reusable Respiratory
Protection Device," and filed on May 15, 2019, which is herein
incorporated by reference in its entirety.
BACKGROUND
1. Field
[0003] Embodiments of this disclosure relate generally to face
masks for respiratory protection. More specifically, embodiments of
this disclosure relate to an elastomeric half-mask respirator that
prevents at least 95% of most airborne particles (most penetrating
particle size is approximately 0.3 .mu.m) from penetrating the mask
(e.g., "N95" filter class).
2. Related Art
[0004] Various disposable N95 filter masks intended for single use
are known. Additionally, many elastomeric half-masks that are
reusable have been described, but these generally have one or more
drawbacks that limit their appropriate reuse in a health care
setting. For example, most existing masks generally require
replaceable filter cartridges, include exhalation valves, may not
be capable of being cleaned at high temperatures (e.g., greater
than 50.degree. C.), are not autoclavable, contain filtration media
that cannot be cleaned and/or disinfected, and/or are not designed
to limit bioburden accumulation.
SUMMARY
[0005] Embodiments of this disclosure provide an elastomeric
half-mask respirator that is reusable and adapted to filter at
least 95% of airborne particles for both non-oil-based and
oil-based aerosols as well as viable and non-viable microorganisms
(e.g., N95, R95, P95, N99, R99, P99, N100, R100, P100 filter
class), thereby limiting penetration of airborne particles through
the mask to less than 5% of the most penetrating size (e.g., 0.3
.mu.m). Embodiments disclosed herein are cleanable at temperatures
exceeding 50.degree. C., autoclavable, designed with surfaces that
can be easily cleaned, and may be embodied in a single piece that
includes integrated head straps and filters that do not require
removal during cleaning, disinfection, or sterilization. In certain
embodiments, the head straps and filters are detachable and capable
of being reprocessed as separate components and/or being replaced.
Reprocessing protocols (cleaning, disinfection, and/or
sterilization) enable reusability of the respirator. In certain
embodiments, a quick field reprocessing protocol enables additional
reuses between extended reprocessing protocols, which are further
described below as including more thorough reprocessing treatments
(e.g., washer-disinfector, autoclave, etc.).
[0006] In an embodiment, a reusable respiratory protection device
includes a mask adapted for covering a portion of a user's face.
The mask includes a face seal adapted to conform to a user's face
around a nose and a mouth of the user, an outer surface, at least
one outer shield portion formed in the outer surface, and at least
one closeable vent through the at least one outer shield portion.
The reusable respiratory protection device further includes at
least one particulate air filter adapted to filter at least 95% of
airborne particles. The at least one particulate air filter is
housed within the at least one outer shield portion. The at least
one closeable vent is adapted to direct air flow through the outer
surface for filtering by the at least one particulate air filter.
The outer surface is substantially smooth to mitigate bioburden
accumulation and wettable to allow for cleaning, disinfection, or
sterilization thereof. A strap is configured to secure the mask to
the user's face.
[0007] In another embodiment, a reusable respirator includes a
unitary mask formed of a single piece of material adapted for
covering a portion of a user's face. The mask includes a face seal
adapted to conform to a user's face around a nose and a mouth of
the user, an outer surface, a first outer shield portion formed in
the outer surface, a first vent through the first outer shield
portion, a second outer shield portion formed in the outer surface,
and a second vent through the second outer shield portion. A first
particulate air filter, housed within the first outer shield
portion, is adapted to filter at least 95% of airborne particles. A
second particulate air filter, housed within the second outer
shield portion, is adapted to filter at least 95% of airborne
particles. The first vent and the second vent are each adapted to
direct air flow to the first particulate air filter and the second
particulate air filter, respectively. The outer surface of the mask
is substantially smooth to mitigate bioburden accumulation and
wettable to allow for cleaning, disinfection, or sterilization
thereof.
[0008] In yet another embodiment, a method for processing a
respirator for reuse includes a) providing a reusable respirator.
The reusable respirator includes a mask adapted for covering a
portion of a user's face. The mask includes a face seal adapted to
conform to a user's face around a nose and a mouth of the user, an
outer surface, at least one outer shield portion formed in the
outer surface, and at least one closeable vent through the at least
one outer shield portion. At least one particulate air filter,
housed within the at least one outer shield portion, is adapted to
filter at least 95% of airborne particles. The at least one
closeable vent is adapted to direct air flow through the outer
surface for filtering by the at least one particulate air filter.
The outer surface is substantially smooth and wettable to allow for
disinfection thereof. A strap is configured to secure the mask to
the user's face. The method further includes b) using the reusable
respirator in a field, and c) performing an extended reprocessing
protocol.
[0009] This summary is provided to introduce a selection of
concepts in a simplified form that are further described below in
the detailed description. This summary is not intended to identify
key features or essential features of the claimed subject matter,
nor is it intended to be used to limit the scope of the claimed
subject matter. Other aspects and advantages will be apparent from
the following detailed description of the embodiments and the
accompanying drawing figures.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
[0010] Embodiments of this disclosure are described in detail below
with reference to the attached drawing figures, wherein:
[0011] FIG. 1 is a first embodiment of a reusable respiratory
protection device;
[0012] FIG. 2 is a perspective view of the reusable respiratory
protection device of FIG. 1;
[0013] FIG. 3 is an exploded view of the reusable respiratory
protection device of FIG. 1;
[0014] FIG. 4 is a perspective backside view of a mask of the
reusable respiratory protection device of FIG. 1;
[0015] FIG. 5 is a cross-sectional bottom view of the mask of the
reusable respiratory protection device of FIG. 1, in an
embodiment.
[0016] FIG. 6 is another cross-sectional bottom view of the mask of
the reusable respiratory protection device of FIG. 1;
[0017] FIG. 7 is a flow diagram of a respirator reuse method for a
reusable respiratory protection device, in an embodiment;
[0018] FIG. 8 shows a machine that is designed to receive the
respirator for performing the process of the invention;
[0019] FIG. 9 shows an exemplary hardware platform for certain
embodiments of the invention;
[0020] FIG. 10 shows a second embodiment of a reusable respiratory
protection device; and
[0021] FIG. 11 is an exploded view showing components of the
reusable respiratory protection device of FIG. 10.
[0022] The drawing figures do not limit the invention to the
specific embodiments disclosed and described herein. The drawings
are not necessarily to scale, emphasis instead being placed upon
clearly illustrating the principles of the invention.
DETAILED DESCRIPTION
[0023] The following detailed description references the
accompanying drawings that illustrate specific embodiments in which
the invention can be practiced. The embodiments are intended to
describe aspects of the invention in sufficient detail to enable
those skilled in the art to practice the invention. Other
embodiments can be utilized and changes can be made without
departing from the scope of the invention. The following detailed
description is, therefore, not to be taken in a limiting sense. The
scope of the invention is defined only by the appended claims,
along with the full scope of equivalents to which such claims are
entitled.
[0024] In this description, references to "one embodiment," "an
embodiment," "the embodiment," or "embodiments" mean that the
feature or features being referred to are included in at least one
embodiment of the technology. Separate references to "one
embodiment," "an embodiment," "the embodiment," or "embodiments" in
this description do not necessarily refer to the same embodiment
and are also not mutually exclusive unless so stated and/or except
as will be readily apparent to those skilled in the art from the
description. For example, a feature, structure, act, etc. described
in one embodiment may also be included in other embodiments but is
not necessarily included. Thus, the technology can include a
variety of combinations and/or integrations of the embodiments
described herein.
[0025] Respirators provide respiratory protection against
atmospheres with airborne respiratory hazards (e.g., particles,
microorganisms, dusts, mists, oils) including viable and non-viable
airborne particles. Air-purifying respirators are designed for use
in an atmosphere that provides adequate oxygen to support life
since no supplemental oxygen is provided (as in a self-contained
breathing apparatus). Respirators can be powered or unpowered.
Powered air-purifying respirators (PAPRs) supply filtered air to a
mask with a positive pressure air blower that may or may not be
breath-assisted. Non-powered air-purifying respirators use the
user's negative inhalation pressure to draw ambient air through
filters to remove particulates from the ambient air and use a
positive pressure exhaled from the wearer to trap any particulates
that may be exhaled.
[0026] Non-powered air-purifying respirators generally fall into
one of two categories: 1) filtering facepiece respirators (FFRs),
or 2) half-mask elastomeric respirators (HMERs). FFRs are generally
respirators in which the facepiece is formed of the filter material
in either a preformed "cup" style, flat fold type, or duck bill
type. FFRs are generally designed for single use because the filter
material is not wettable per manufacturer guidance, which prevents
the FFR from being cleaned, disinfected or sterilized (e.g., washed
or disinfected with a disinfectant solution, washer-disinfector,
ultrasonicator, sterilized via steam autoclave, chemical sterilant,
etc.) for subsequent reuse. FFRs are also constructed using
materials and methods that are not intended to support reusability
(e.g., durability). FFRs are lighter than half-mask elastomeric
respirators and typically discarded after a single use to avoid
acting as a fomite by spreading infectious diseases, making them
preferred in health care settings. Many FFRs are approved by the
National Institute for Occupational Safety and Health (NIOSH) and
cleared for use in hospital settings by the U.S. Food & Drug
Administration (FDA). During an infectious disease pandemic, such
as an influenza or coronavirus pandemic, a large number of
respirators are needed, especially for health care workers.
Single-use respirators, such as FFRs, will quickly be consumed
during a pandemic lasting weeks or months, thus requiring an
alternative approach to stockpiling and meeting the expected
demand.
[0027] HMERs generally include a molded facepiece to which
replaceable filtering cartridges may be attached. The mask itself
is reusable, whereas the filtering cartridges are generally
replaceable since the filter material cannot be cleaned or
decontaminated (e.g., washed, disinfected, or steam sterilized)
because they cannot be wetted per manufacturer guidance. Cleaning
of HMERs in hospitals is time consuming, tedious, and prone to
error for use, and they are not designed to withstand the moisture,
temperature, and pressures of autoclaves and washer-disinfectors.
HMERs also contain a number of grooves, crevices, materials, and
design features that render them difficult to clean. Additionally,
HMERs have not been cleared for use in the medical setting by the
U.S. FDA.
[0028] Embodiments of this disclosure provide a single-piece HMER
that is reusable and adapted to filter at least 95% of the most
penetrating airborne particles. Respirators providing at least 95%
efficiency at filtering airborne particles of the most penetrating
size are referred to as being in the "P-, R-, or N95" filter class,
per 42 C.F.R. Part 84. In other embodiments, the filter may be
adapted to achieve higher levels of filtration efficiency in
accordance with NIOSH requirements for P-, R-, or N99 filters
and/or P-, R-, or N100 filters. N-series filters are restricted for
use in environments free of oil aerosols. The R- and P-series
filters are intended for removal of any particulate that includes
oil-based liquid particulates. In addition to filtration
efficiency, embodiments of the filter will meet or exceed (e.g.,
lower than maximum value) the maximum inhalation resistance and
exhalation resistance values as defined in 42 CFR Part 84.
Embodiments disclosed herein differ from conventional HMERs in that
the filter media can be disinfected and/or sterilized via aqueous
cleaning mechanisms (detergents, alcohol, bleach, etc.) and
sterilization practices to effectively remove and/or otherwise
render inert all contamination species. Certain embodiments include
integrated or detachable straps, allowing the device to be donned
similar to current FFRs. Certain embodiments include fixed or
removable filters, allowing for integrated or separate
reprocessing, respectively. The result is a sustainably reusable
fully integrated respirator meeting NIOSH requirements as defined
in 42 CFR Part 84 for a P-, R-series, or N-series filter with at
least 95% filtration efficiency (e.g., P95, P99, P100, R95, R99,
R100, N95, N99, N100). Additionally, the respirator provides an
assigned protection factor greater than or equal to 10 as required
for air-purifying respirators by the Occupational Safety and Health
Administration under 29 CFR 1910.
[0029] FIG. 1 is a frontside view of an exemplary reusable
respiratory protection device 100, which includes a mask 110 and
straps 161, 162 configured for wearing on a user's face. The
reusable respiratory protection device 100 may be referred to
herein as "respirator 100" for short. The respirator 100 is an
example of an elastomeric half-mask reusable respirator.
Specifically, in one embodiment, the mask 110 is a half mask,
meaning that it covers the lower half of the user's face including
the nose and mouth, but not the eyes. The respirator 100 is adapted
to be lightweight for improved comfort, especially for health care
workers who may wear a respirator for long durations. For example,
the respirator 100 is adapted to be lighter than existing
elastomeric half-mask respirators due to the use of lighter and
fewer materials. In certain embodiments, the mask weighs between
about 3-oz. to about 4-oz. In other embodiments, the mask may weigh
between 2-oz.-5 oz, or less than 2-oz, or greater than 5-oz.
[0030] The respirator 100 is adapted to have a shelf life longer
than that of existing N95 FFRs, which is typically three to five
years, due to the use of more durable materials and construction.
In certain embodiments, the rated shelf life of respirator 100 is
expected to be between ten and twenty years.
[0031] The mask 110 and straps 161, 162 provide a substantially
smooth semi-rigid protective surface adapted for compatibility with
cleaning and disinfection wiping protocols, which extends the life
cycle of respirator 100 by allowing it to sustain numerous
disinfections and/or sterilization cycles. Specifically, the mask
110 and straps 161, 162 include a smooth wettable surface that is
adapted to be easily cleanable. The mask 110 and straps 161, 162
lack small edges, corners, and nooks to make surfaces easily
accessible for wiping with disinfectant to avoid bioburden, such as
a buildup of microorganisms. The mask 110 and straps 161, 162 are
made of a material that is resistant to common disinfectants, such
as isopropyl alcohol, benzalkonium chloride, hypochlorite or
quaternary amines, for example. An exemplary material for the mask
110 and/or straps 161, 162 is silicone.
[0032] In one embodiment, due to the fact that the mask 110 and
straps 161, 162 can be molded as a single piece of material, this
feature further enables rapid and effective cleaning since the mask
110 and straps 161, 162 lack creases, bond lines, or other
mechanical connections between separate components that could
accumulate bioburden. Specifically, the mask 110 can be a unitary
piece that includes a face seal 150 (described below in connection
with FIG. 4), a first outer shield portion 131 and a second outer
shield portion 132 formed in an outer surface of the mask 110
(described below in connection with FIG. 2) and a first vent 171
and a second vent 172 through the first and second outer shields
131, 132, respectively (described below in connection with FIG. 4).
The single piece design also enhances the ability of the respirator
100 to withstand an automated cleaning regimen for rapid and
repeated cleaning/sterilization without degradation that otherwise
might initiate along bond lines or other mechanical
connections.
[0033] FIG. 2 is a perspective view of respirator 100 of FIG. 1.
FIGS. 1 and 2 are best viewed together with the following
description. The first outer shield portion 131 and the second
outer shield portion 132 are portions of the mask 110 that protrude
from the front of the mask 110 on either side (e.g., left or
right). The first and second outer shield portions 131, 132 are
formed as part of the material of the mask 110 and shaped to house
and protect an inner filter material for purifying air (e.g.,
particulate air filters 141, 142, described below in connection
with FIGS. 3 and 5). Specifically, the outer shield portions 131,
132 each forms a protective pocket for housing and protecting the
inner filter material (e.g., protective pockets 133, 134 described
below in connection with FIG. 6). The outer shield portions 131,
132 serve as a splashguard to protect the inner filter material
from fluids that may be burdened with biological contamination
(e.g., blood, saliva, and cough/sneeze droplets). The outer shield
portions 131, 132 also provide protection of the inner filter
material from damage due to impact.
[0034] Straps 161, 162 provide an integrated harness for
maintaining the mask 110 comfortably against the user's face. The
strap may be formed of a single piece of material or two or more
pieces of material. For example, as depicted in FIGS. 1-3, the
strap includes an upper strap 161 and a lower strap 162, but
alternative strap arrangements may be employed without departing
from the scope hereof. For example, a unitary strap having an upper
band and a lower band may be employed. An exemplary material for
the strap is silicone, however other elastomeric, stretchable,
and/or conformable materials may be used. This enables the strap to
be stretched for assisting with donning and doffing the respirator
100, such that the strap has a first elongated length when
stretched for placing over the user's head, and a second contracted
length while being worn to securely maintain the mask 110 on the
user's head. In some embodiments, the fixed contracted length of
the strap may be adapted for a specified size range (e.g., to
provide proper fit for different head sizes). However, the strap
may optionally include a length-adjusting feature (e.g., a
gathering clip), without departing from the scope hereof. The strap
may be attached to the mask 110 in an integrated or detachable
manner. To prevent hearing impairment, the strap is adapted to
avoid the user's ears. As further described below, the strap is
adapted to be easily cleaned and sterilized together with the mask
110 without needing to be detached. In other embodiments, the
straps can be detached for cleaning, disinfection and/or
sterilization.
[0035] FIG. 3 is an exploded view of respirator 100 for viewing
internal components. Not all components of respirator 100 are
depicted in FIG. 3 for clarity of illustration. The respirator 100
includes the mask 110, the straps 161, 162, a first particulate air
filter 141, and a first filter rim 145 adapted for holding the
first particulate air filter 141. A second particulate air filter
142 and a second filter rim 146 are shown in FIG. 5. In certain
embodiments, each particulate air filter 141, 142 is surrounded
about its circumferential edge by a respective filter rim 145, 146.
In some embodiments, the filter rim 145, 146 may be made of
polypropylene, although other materials (e.g., silicone) may be
used. In some embodiments, the particulate air filters 141, 142 and
the filter rims 145, 146 may be formed together by overmolding.
Each particulate air filter 141, 142, secured within its respective
filter rim 145, 146, can then inserted be into one of the outer
shield portions 131, 132 of the mask 110. The mask 110 is
configured such that the outer shield portions 131, 132 stretch to
form a tight seal around each of the air filters 141, 142,
respectively. In certain embodiments, the air filters 141, 142 may
be sealed to the mask 110 via overmolding or other appropriate
manufacturing process. Each of the air filters 141, 142, and its
respective filter rim 145, 146, may be inserted into one of the
outer shield portions 131, 132 of the mask 110 by hand, or by
automated methods (e.g., robotics), or other manufacturing methods
(e.g., overmolding). In some embodiments, the air filters 141, 142
are removable from the mask 110, but in other embodiments the air
filters 141, 142 are not removable.
[0036] In some embodiments, the first vent 171 provides an air
passage that connects the first particulate air filter 141 to
outside the mask 110. Similarly, the second vent 172 (see FIG. 4)
provides an air passage that connects the second particulate air
filter 142 to outside the mask 110. In one embodiment, the first
and second vents 171, 172 face downwardly and back towards the user
and are further described below in connection with FIGS. 4-6.
[0037] In one embodiment, the first and second particulate air
filters 141, 142 are made of a filter media or other material
adapted to purify respirable air by filtering airborne particles,
which prevents inhalation of the particles by the user of
respirator 100. The filter media may be pleated, with a number of
pleats being adapted for improved ventilation. Pleating the media
increases the filter surface area which reduces breathing
resistance. Other embodiments may use non-pleated media.
[0038] In an embodiment, first and second particulate air filters
141, 142 are adapted to exceed NIOSH requirements for the P-, R-,
or N95 filter class. Other embodiments contain air filters adapted
to exceed NIOSH requirements for the P-, R-, or N99 filter class,
or P-, R-, or N100 filter class. In some embodiments, the
particulate air filters 141, 142 are adapted to meet or exceed the
European EN 143 guidance requirements. The thickness of the
particulate air filters 141, 142 is adapted to be thin enough to
maximize the amount of pleated or non-pleated media in the
respirator to improve ventilation, lower breathing resistance, and
increase speech intelligibility. A pressure drop across the
particulate air filters 141, 142 may be used to measure the
relative ease of breathing while wearing a respirator. For example,
the NIOSH-mandated maximum inhalational pressure drop for an N95
respirator is 25 mm-H.sub.2O. The respirator 100 is adapted to meet
or exceed (lower than max value) this maximum inhalation pressure
drop even after numerous cleaning/sterilizing protocols (e.g., see
the extended reprocessing protocol Step 210, described below in
connection with FIG. 7). A target goal of 10 mm-H.sub.2O has been
established by Project BREATHE (Radonovich L. et al., Better
respiratory equipment using advanced technologies for healthcare
employees (Project B.R.E.A.T.H.E.): A report of an interagency
working group of the U.S. federal government. 2009.
http://www.publichealth.va.gov/docs/cohic/projectbreathe-report-2009.pdf)-
. In certain embodiments, the respirator 100 may be adapted to meet
or exceed this goal pressure drop.
[0039] Each of the first and second particulate air filters 141,
142 may include a protective coating or protective layer 147
disposed on one or both sides of the filter media, in some
embodiments. The protective coating/layer 147 is substantially air
permeable and substantially hydrophobic to mitigate contamination
and wetting of the filter media for prolonging its integrity. The
protective coating/layer 147 is, for example, a polypropylene or
polyethylene layer that would protect the inner layer. In some
embodiments, the filter media contains a polytetrafluoroethylene
(PTFE) layer, which is substantially air permeable and
substantially hydrophobic. The PTFE layer is preferably located
between two protective layers 147 or affixed to a single protective
layer 147. The particulate air filters 141, 142 may include other
types of filter media, without departing from the scope hereof,
such as high-efficiency particulate air (HEPA) filters and
ultra-low particulate air (ULPA) filters or vapor capture materials
(e.g., carbon). Other types of filter media such as microglass may
be used without departing from the scope hereof, although a
non-shedding filter media is preferable for durability and user
safety.
[0040] In some embodiments, the first and second particulate air
filters 141, 142 are capable of being cleaned, disinfected, and/or
sterilized. In some embodiments, the particulate air filters 141,
142 may be cleaned with detergents and/or enzymes using manual or
automated methods. In some embodiments, the particulate air filters
141, 142 may be cleaned using ultrasonic baths and/or
washer-disinfectors. In other embodiments, particulate air filters
141, 142 may be disinfected with isopropyl alcohol, bleach,
hydrogen peroxide, or other known disinfectants. In other
embodiments, particulate air filters 141, 142 may be sterilized
using an autoclave, gamma radiation, VHP, EtO, or other known
sterilization methods. In some embodiments, the particulate air
filters 141, 142 may be cleaned, disinfected, and/or sterilized
while still housed within the respirator 100. In other embodiments,
particulate air filters 141, 142 may be removed from the respirator
100 for separate cleaning, disinfecting, or sterilization.
[0041] The mask 110 may include an optional inner layer 190, in
some embodiments, located between the first and/or second
particulate air filter 141, 142 and the user for reducing
accumulation of breath secretions on the first and second
particulate air filters 141, 142. The inner layer 190 may include a
removable washable, flexible insert (e.g., scrim) that provides a
protective surface covering each of particulate air filters 141,
142 on the innermost portion of the mask 110 facing the user. In
other embodiments, the inner layer 190 may be provided as a unitary
part of the particulate air filter 141, 142. The inner layer 190
may further extend the life cycle of the respirator 100 by
protecting the filter media during disinfection, cleaning, and/or
sterilization processes. The inner layer 190 is composed of, for
example, a flexible mesh fabric. Exemplary materials for the inner
layer 190 include, but are not limited to, polyolefin,
polypropylene, polyethylene, and/or polyphenylsulfone. Other
flexible materials are also possible. The inner layer 190 may be
removably attached to the filters 141, 142, permanently attached to
the filters 141, 142, filter overmolded, or could be a stand-alone
part.
[0042] In some embodiments, the respirator 100 may further include
a speech diaphragm, microphone and/or a wireless transmitter to
allow a user to communicate better.
[0043] FIG. 4 is a perspective backside view of mask 110 of
respirator 100. Upper and lower 161, 162 straps are not shown for
clarity of illustration. The face seal 150 is adapted to
comfortably fit over the user's nose and mouth and form an airtight
seal against the user's face. The face seal 150 includes a main
pocket 155 that encloses the user's nose and mouth and permits
ample air exchange with the first and second particulate air
filters 141, 142.
[0044] The face seal 150 includes a nose bridge 151 adapted to
extend over the bridge of the user's nose and a chin pocket 152
adapted to extend below the user's chin, which provide the face
seal 150 with a positive location that is stabilized by the lower
strap 162 to ensure seal integrity. The outer profile of the face
seal 150 is compact below the nose so as to reduce interference
with the user's field of vision and to avoid interference with
eyewear (e.g., glasses) or other personal protective equipment
(e.g., face shield). The face seal 150 is adapted to fit a large
variety of different face sizes and shapes. The mask 110, including
the face seal 150, may be manufactured in a variety of sizes (e.g.,
infant, child, small, medium, large, etc.) to provide proper fit
for different head sizes ranging from pediatric to adult head
sizes. In certain embodiments, the face seal 150 is made of
silicone or thermoplastic elastomer and is adapted to reduce facial
discomfort. In some embodiments, other conformable materials may be
used for the face seal 150.
[0045] FIG. 5 is a cross-sectional bottom view of the mask 110 that
shows the first and second particulate air filters 141, 142, which
are located internally within the first and second outer shield
portions 131, 132 of the mask 110. FIG. 6 is a cross-sectional
bottom view of the mask 110 with the first and second particulate
air filters 141, 142 shown removed. FIGS. 5 and 6 are best viewed
together with the following description.
[0046] A first protective pocket 133 houses the first particulate
air filter 141, and a second protective pocket 134 houses the
second particulate air filter 142. The first and second protective
pockets 133, 134 are formed within the first and second outer
shields, 131, 132, respectively.
[0047] A first gap 181 is formed between the first outer shield
portion 131 and the first particulate air filter 141, as depicted
in FIGS. 5 and 6. Similarly, the second outer shield portion 132 is
shaped to form a second gap 182 between the second outer shield 132
and the second particulate air filter 142. The first and second
gaps 181, 182 provide ample space to disperse flow of air evenly
across the surface of each of the particulate air filters 141, 142,
which ensures efficient filter media utilization and low resistance
to air flow. The first gap 181 extends to the first vent 171 (e.g.,
see FIG. 4) to connect the air passage to the outside. Similarly,
the second gap 182 extends to the second vent 172 (e.g., see FIG.
4), to connect the air passage to the outside. In one embodiment,
the first vent 171 and the second vent 172 are formed of a flexible
material so as to be selectively closeable. Alternatively, in
another embodiment, the vents 171, 172 may be a rigid opening in
the outer surface of the mask for allowing airflow
therethrough.
[0048] In operation, as a user of respirator 100 inhales, air is
drawn into the mask 110 via the first and second vents 171, 172,
through respective first and second gaps 181, 182, and across
respective first and second particulate air filters 141, 142.
Particles in the air are filtered by the first and second
particulate air filters 141, 142, and purified air is delivered to
the main pocket 155 within mask 110 for inhalation by the user.
When exhaling, the exhaled breath of the user passes in the
opposite direction through the air filters 141, 142 across the gaps
181, 182, and out of the mask 110 via the vents 171, 172.
[0049] The mask 110 includes a built-in user seal check method
adapted for the user of the respirator 100 to ensure facial seal
integrity with the mask 110. The user seal check method allows the
user of the respirator 100 to test that the face seal 150 provides
a proper airtight seal before using the respirator 100 in the
field. Along an underside of the first and second outer shield
portions 131, 132, where the first and second vents 171, 172 are
formed, the mask 110 is adapted to be flexible, thus enabling
temporary closure of the vents.
[0050] To test the seal, the outer shield portions 131, 132 can
each be deflected inward against the outer surface of the mask 110
to temporarily close the closeable vents 171, 172. Specifically,
the user presses inwardly (e.g., with a finger) on the outer-lower
region of the first outer shield portion 131 in such a manner that
the first vent 171 closes. Similarly, the user presses inwardly
(e.g., with another finger) on the outer-lower region of the second
outer shield portion 132 in such a manner that the second vent 172
closes. With both of the vents 171, 172 simultaneously closed, the
user inhales, and if a proper airtight seal is formed, a slight
inhalation vacuum results, which pulls the mask against the user's
face confirming a proper facial seal. Otherwise, if a leak exists
along the face seal 150, the user can detect the leak as air rushes
in against the user's face and a lack of vacuum upon inhalation.
Upon release of the lower region of the first and second outer
shield portions 131, 132, the first and second vents 171, 172,
respectively, return to their original shape. This re-opens the
vents 171, 172, providing ports for air exchange with the first and
second particulate air filters 141, 142, respectively.
[0051] FIG. 7 is a flow diagram of an exemplary respirator reuse
method 200 adapted for reuse of respirator 100 or respirator 300
(see FIGS. 8 and 9 and their description below). Respirators 100
and 300 are adapted for cleaning, disinfection, and/or
sterilization using a variety of protocols, which may be employed
in various combinations to increase the number of reuses, as
described below in connection with FIG. 7. Although the below
protocols are discussed with respect to respirator 100, similar
protocols could be performed on respirator 300.
[0052] Embodiments may include performing a high-level
sterilization process that includes cleaning the respirator 100
followed by autoclave treatment. Other sterilization processes such
as vaporized hydrogen peroxide, ethylene oxide, gamma irradiation,
etc. are envisioned. Embodiments may include performing a
disinfection process that includes cleaning the respirator 100
followed by disinfection via washer-disinfector, chemical
disinfection, heat disinfection, etc. Embodiments may include
performing a quick field reprocessing protocol, which may include
manually cleaning and disinfecting the respirator 100, 300 by an
operator or assigned staff.
[0053] More specifically, in Step 210, an extended reprocessing
protocol is performed. In one embodiment, the extended reprocessing
protocol 210 involves cleaning, disinfecting and/or sterilizing
steps using specialized equipment that may be found in a hospital
or other health care setting, such as an autoclave,
washer-disinfector, gamma radiation, VHP, EtO, ultrasonic bath,
etc. The respirator 100 is adapted to be fully autoclavable,
cleanable, and/or disinfectable as a single unit (e.g., without
requiring any disassembly and reassembly), including with the first
and second particulate air filters 141, 142, as well as with the
upper and lower straps 161, 162 attached.
[0054] In certain embodiments, the first and second particulate air
filters 141, 142, as well as the upper and lower straps 161, 162
may be disassembled and processed separately using the extended
reprocessing protocol of Step 210. In an example of Step 210, the
respirator 100 is subjected to a cleaning and/or disinfecting step
in a washer-disinfector at about >50.degree. C. or an ultrasonic
bath after retrieval from the field (see Step 240, described
below); and then following washing/cleaning/disinfecting, the
respirator 100 is subjected to autoclaving (e.g., steam
sterilization application of high temperature and pressure) for a
predetermined duration. The order of the cleaning/disinfecting and
autoclaving steps may be reversed in some embodiments. In some
embodiments, a pre-rinse to the respirator may be included. An
exemplary extended reprocessing protocol is an OSHA protocol
defined under 29 CFR 1910.134. Another embodiment of the cleaning
and sterilization process allows the respirator to be disassembled
and each part undergoes a separate cleaning and sterilization
process.
[0055] As an alternative to above-described processing methods, the
extended reprocessing protocol 210 may include cleaning and drying
the respirator 100 at home for personal reuse using a washing
machine or dishwasher, and then a residential dryer if
necessary.
[0056] Reuse of the filter media following
cleaning/disinfection/sterilization processing is an advantage for
the reusability of the respirator 100. A greater number of reuses
provides a lower cost per use, reduces the need for stockpiling of
respirators in preparation for a pandemic, and maintains
availability of clean respirators during a pandemic. In certain
embodiments, the extended reprocessing protocol of Step 210 enables
safe reuse of respirator 100 for at least one hundred reuses.
[0057] In Step 220, the respirator 100 is used in the field. In an
example of Step 220, the respirator 100 is deployed for use in the
field after extended reprocessing protocol 210. In another example
of Step 220, the respirator 100 is deployed for use in the field
after a quick field reprocessing protocol is performed (see Step
230, described below). Here the term "field" is meant to broadly
include any indoor or outdoor location where the respirator 100 may
be worn by a user, including but not limited to hospitals, clinics,
other occupational settings, homes, businesses, parks, gyms, and
while traveling via transportation vehicles (e.g., airplanes,
ships, trains, automobiles, bicycles, scooters, etc.).
[0058] In Step 230, a quick field reprocessing protocol is
performed. In an example of Step 230, the respirator 100 is wiped
down with a disinfectant material or a disinfecting wipe. In
another example of Step 230, at least a portion of the respirator
100 is cleaned with a detergent, then disinfected with a wipe or
spray. In some embodiments, only the exterior surfaces of the mask
110 (including those surfaces facing the user) are
cleaned/disinfected. In other embodiments, the mask 110 and straps
161, 162 are cleaned/disinfected. In some embodiments, the
respirator 100 may be disinfected with isopropyl alcohol, bleach,
hydrogen peroxide, or other known disinfectants. The quick field
reprocessing protocol may be quickly performed (e.g., in less than
one minute) without needing specialized cleaning equipment such as
an autoclave, washer-disinfector, or ultrasonic bath. The quick
field reprocessing protocol is intended to be performed a
predetermined number of times (e.g., five or more) to provide a
limited number of reuses before performing the extended
reprocessing protocol referenced in Step 210.
[0059] The quick field reprocessing protocol may include steps
intended to ensure adequate disinfection based on
standard-operating-procedures that adhere to tested and
well-defined health care practices. For example, the quick field
reprocessing protocol may stipulate an appropriate disinfectant, a
preferred sequence of surfaces to wipe, a sufficient duration for
wiping and a sufficient contact time of the disinfectant. The quick
field reprocessing protocol may stipulate steps for the safety of
the person performing the protocol, such as instructions for
wearing safety gloves, a lab coat, safety glasses, etc.
Additionally, the quick field reprocessing protocol may stipulate
steps for appropriate disposal of the wipes (e.g., instructions
regarding local regulations for the handling and disposal of
biohazardous waste). The quick field reprocessing protocol 230 may
be performed while the respirator is worn by the user. Due to the
smooth wipeable surfaces of the mask 110 and straps 161, 162, the
user is able to easily wipe down the mask 110 prior to donning and
doffing to mitigate self-contamination.
[0060] Following Step 230, the respirator reuse method 200 returns
to Step 220 for reusing the respirator in the field. The respirator
reuse method 200 is intended to proceed back and forth between Step
220 and Step 230 a limited number of times before the respirator
reuse method 200 proceeds with Step 240, described below, for
retrieval of the respirator 100 from the field. The number of uses
(in Step 220) and optionally the number of subsequent quick field
reprocessing protocols (in Step 230) that are performed in between
extended reprocessing protocols (in Step 210) may be tracked as
part of a use monitoring program, as further described below in
connection with Step 250. Alternatively, the respirator reuse
method may be performed without Step 230 entirely.
[0061] When Step 210 and Step 230 are both performed, the number of
quick field reprocessing protocols between each extended
reprocessing protocol results is a multiplier of the available
number of uses. For example, if the respirator 100 is processed by
the quick field reprocessing protocol 230 five times between each
extended reprocessing protocol 210, the respirator 100 would be
then be able to be used six hundred times rather than one
hundred.
[0062] In Step 240, the respirator is retrieved from the field. The
respirator may be retrieved from the field after a predetermined
number (e.g., five) of quick-field disinfections, or fewer/longer,
as performed in Step 230. In an example of Step 240, a health care
worker turns in their respirator 100 to a health care facility
equipped with specialized equipment for performing an extended
reprocessing protocol in Step 210. In an example of Step 240 for
personal use, a user places the respirator 100 in a home dishwasher
or home washing machine for cleaning in Step 210.
[0063] In an optional Step 250, monitoring the use and reprocessing
of the respirator is performed for the purposes of life cycle
management. In an example of Step 250, the respirator 100 is
tracked as part of a use monitoring program. An identification tag
105, shown in FIGS. 2 and 3, may be attached to the respirator 100
for quickly identifying individual respirators as part of the use
monitoring program. An example of the identification tag 105 is a
scannable identification tag, including but not limited to a
barcode or a radio-frequency identification (RFID) tag, which may
be scanned with a scanning device for quickly identifying a
respirator 100 and indicating its current use category. The barcode
may be a one-dimensional (1D) barcode, a two-dimensional (2D), or a
matrix barcode such as a Quick Response (QR) code. Alternatively, a
RFID tag may be attached to, or embedded within, the respirator 100
for identifying each respirator unit (e.g., via a serial number)
and for tracking its use and disinfection. Other types of tracking
devices or markers 105 may also be used.
[0064] For example, in connection with Step 210, following
completion of the extended reprocessing protocol, or optionally at
intermediate steps throughout the reprocessing protocol, individual
respirators 100 are scanned for tracking their status via a
processor within a database. Use monitoring may be performed in
connection with any of the steps of the respirator reuse method
200. For example, following each use in the field (Step 220),
and/or following each quick field reprocessing protocol (Step 230),
and/or following each extended reprocessing protocol 210, and/or
following retrieval of the respirator (Step 240), respirator 100
may be scanned for updating the database accordingly. The database
may also be accessed from a mobile device (e.g., smartphone or
tablet) for remotely updating information (e.g., to indicate that a
quick field reprocessing protocol 230 has been performed in the
field).
[0065] The extended reprocessing protocol 200 may be manual or
automated. For example, batch processing of a plurality of
respirators may be accomplished by a machine-automated process.
[0066] FIG. 8 shows an embodiment of a machine 500 designed to
receive the respirator 100 for the extended reprocessing protocol
210. Machine 500 may include a first stage 502 where
disinfection/cleaning is performed, an optional holding area 504, a
second stage 506 wherein sterilization is performed.
[0067] In some embodiments, the disinfection machine 500 may
include a tracking interface 508 that cooperates with an
identification tag 105 on the respirator to indicate that a
disinfection cycle has been performed. The tracking interface 508
may cooperate with a computer 510 that may have at least one
processor, a graphical user interface, an input device, and a
display for allowing the user to track the disinfection process.
Tracking may include the number of times the disinfection has been
performed on the particular personal protective equipment (PPE),
the locations where the PPE has been used, and the identification
of users of the PPE. The computer 510 may optionally interface with
an inventory management system for assisting with inventory
management and purchasing.
[0068] The computer 510 may also allow a user to control all
aspects of the process, including the predetermined amounts of time
for each of the steps, the desired concentrations for any
disinfecting solutions being applied, a temperature for
sterilization, and the type of sterilization to be applied. The
machine 500 is capable of processing one respirator or a plurality
of respirators simultaneously. The machine 500 may include a
bar-code reader or other scanner or tracking device for receiving
information from each respirator to be treated, which may be read
from an indicator, such as identification tag 105.
[0069] For purposes of life cycle management of the respirator, the
machine 500 may manually receive the age of the respirator from the
operator or may automatically detect the age of the respirator. The
machine 500 may include an automatic detection mechanism for
determining the age of the respirator, such as by a spectral scan
of the material, a measurement of the off-gassing or volatile
materials, or a particular response to the disinfection process.
The machine 500 may alternatively or additionally detect the age of
the PPE from identification tag 105 on the respirator, which may be
cross-referenced with a database tracking system. The machine 500
may alternatively or additionally use the identification tag 105 to
correlate the number of allowable disinfection cycles with a
look-up table containing the useful life for various respirator and
contamination levels/types. The machine 500 may include a mechanism
for providing an alert, which may be visual and/or audio, when the
respirator has exceeded the allowable number of disinfection
cycles.
[0070] The disinfection machine 500 may include racks designed to
support the respirator such that all outer surfaces can be evenly
treated during the process. The racks may be extendable and/or
interchangeable depending on what type/size of respirator is to be
disinfected. The machine 500 may include hooks for hanging the
straps of the respirator thereon.
[0071] In some embodiments, central computer 510 that is part of
machine 500 described in reference to FIG. 8 may be a computer 702
as described with reference to FIG. 9.
[0072] FIG. 9 shows an exemplary hardware platform for certain
embodiments of the invention. Computer 702 can be a desktop
computer, a laptop computer, a server computer, a mobile device
such as a smartphone or tablet, or any other form factor of
general- or special-purpose computing device. Depicted with
computer 702 are several components, for illustrative purposes. In
some embodiments, certain components may be arranged differently or
absent. Additional components may also be present. Included in
computer 702 is system bus 704, whereby other components of
computer 702 can communicate with each other. In certain
embodiments, there may be multiple busses or components may
communicate with each other directly. Connected to system bus 704
is central processing unit (CPU) 706. Also attached to system bus
704 are one or more random-access memory (RAM) modules 708. Also
attached to system bus 704 is graphics card 710. In some
embodiments, graphics card 710 may not be a physically separate
card, but rather may be integrated into the motherboard or the CPU
706. In some embodiments, graphics card 710 has a separate
graphics-processing unit (GPU) 712, which can be used for graphics
processing or for general purpose computing (GPGPU). Also on
graphics card 710 is GPU memory 714. Connected (directly or
indirectly) to graphics card 710 is display 716 for user
interaction. In some embodiments, no display is present, while in
others it is integrated into computer 702. Similarly, peripherals
such as keyboard 718 and mouse 720 are connected to system bus 704.
Like display 716, these peripherals may be integrated into computer
702 or absent. Also connected to system bus 704 is local storage
722, which may be any form of computer-readable media and may be
internally installed in computer 702 or externally and removably
attached.
[0073] Computer-readable media include both volatile and
nonvolatile media, removable and nonremovable media, and
contemplate media readable by a database. For example,
computer-readable media include (but are not limited to) RAM, ROM,
EEPROM, flash memory or other memory technology, CD-ROM, digital
versatile discs (DVD), holographic media or other optical disc
storage, magnetic cassettes, magnetic tape, magnetic disk storage,
and other magnetic storage devices. These technologies can store
data temporarily or permanently. However, unless explicitly
specified otherwise, the term "computer-readable media" should not
be construed to include physical, but transitory, forms of signal
transmission such as radio broadcasts, electrical signals through a
wire, or light pulses through a fiber-optic cable. Examples of
stored information include computer-usable instructions, data
structures, program modules, and other data representations.
[0074] Finally, network interface card (NIC) 724 is also attached
to system bus 704 and allows computer 702 to communicate over a
network such as network 726. NIC 724 can be any form of network
interface known in the art, such as Ethernet, ATM, fiber,
Bluetooth, or Wi-Fi (i.e., the IEEE 802.11 family of standards).
NIC 724 connects computer 702 to local network 726, which may also
include one or more other computers, such as computer 728, and
network storage, such as data store 730. Generally, a data store
such as data store 730 may be any repository from which information
can be stored and retrieved as needed. Examples of data stores
include relational or object-oriented databases, spreadsheets, file
systems, flat files, directory services such as LDAP and Active
Directory, or email storage systems. A data store may be accessible
via a complex API (such as, for example, Structured Query
Language), a simple API providing only read, write and seek
operations, or any level of complexity in between. Some data stores
may additionally provide management functions for data sets stored
therein such as backup or versioning. Data stores can be local to a
single computer such as computer 728, accessible on a local network
such as local network 726, or remotely accessible over Internet
732. Local network 726 is in turn connected to Internet 732, which
connects many networks such as local network 726, remote network
734 or directly attached computers such as computer 736. In some
embodiments, computer 702 can itself be directly connected to
Internet 732. Additionally, instructions to perform any of the
steps described in reference to FIG. 7 may be stored on the local
storage 722.
[0075] FIG. 10 shows a second embodiment of an exemplary reusable
respiratory protection device 300 having a mask 310 and a strap
360. The reusable respiratory protection device 300 may be referred
to herein as "respirator 300" for short. The respirator 300 may be
similar to respirator 100, FIG. 1. For example, the mask 310 is
also a half mask that covers the lower portion of the user's face
including the nose and mouth but not the eyes. The respirator 300
is also adapted to be lightweight for improved comfort (e.g.,
between about 3-oz. to about 4-oz).
[0076] A frame 320 provides structural support for other components
and one or more attachment points for the strap 360. A pair of
outer shield portions 330 each serve as a splashguard that protect
an inner filter material, such as particulate air filters 340 (see
FIG. 9) from contamination. Each outer shield portion 330 is
positioned on one side (e.g., left or right) of the mask 310. A
plurality of vents 331 are positioned along the edge of each outer
shield portion 330 for allowing air passage to and from the
particulate air filters 340. Not all vents 331 are enumerated in
FIGS. 10 and 11 for clarity of illustration. The outer shield
portions 330 are compatible with reprocessing protocols, such as
the quick field reprocessing protocol 230, described above in
connection with FIG. 7. A face seal 350 provides an airtight seal
against the wearer's face.
[0077] FIG. 11 shows an exploded view of the respirator 300 of the
embodiment of FIG. 8. The exploded view provides separation between
components of the respirator 300 for clarity of illustration. In
addition to the components depicted in FIG. 10, FIG. 11 illustrates
a particulate air filter 340 and a filter rim 345 adapted for
holding the particulate air filters 340. An optional inner shield
335 may be used in some embodiments for protecting an inner side of
the particulate air filters 340, as further described below. In
certain embodiments, the particulate air filters 340 may include a
pair of air filters 340 each adapted for a left and right side of
mask 310, respectively. Likewise, the optional inner shield 335 may
include a pair of inner shields 335 each adapted for a respective
side of mask 310.
[0078] The face seal 350 includes a nose bridge that extends over
the bridge of the wearer's nose and a chin pocket that extends
below the wearer's chin, which provide the face seal 350 with a
positive location that is stabilized by the strap 360 to ensure
seal integrity.
[0079] In certain embodiments, the frame 320 includes a pair of
frames each adapted for supporting one of the pair of particulate
air filters 340 and one of the pair of outer shield portions 330,
respectively. However, in some embodiments, the frame 320 is molded
as a single component. During manufacture of the mask 310, the
filter rim 345 is overmolded with the frame 320 encapsulating the
particulate air filters 340. The outer shield portions 330 are
coupled with the frame 320 (e.g., overmolded or snap-in) for
protecting the outer side of the particulate air filters 340.
[0080] The outer shield portions 330 include a substantially smooth
surface adapted for protecting the particulate air filters 340 and
for being wettable and washable. Each outer shield portion 330 is
raised above the particulate air filter 340 creating a gap between
the outer shield portion 330 and the frame 320 with an ample plenum
incorporated on the underside of the outer shield portion 330 to
disperse flow evenly across the surface of the particulate air
filters 340 ensuring efficient filter media utilization and low
resistance. The plurality of vents 331 provide ports for passage of
air from outside the respirator 330 to the space behind each outer
shield 330.
[0081] Each outer shield portion 330 provides a semi-rigid
protective surface for covering the underlying particulate air
filter 340. An exemplary material for the outer shield portion 330
is silicone. The outer shield portion 330 is also wettable and
resistant to common disinfectants, such as benzalkonium chloride,
hypochlorite or quaternary amines, for example.
[0082] In general, during wash and disinfecting cycles, mechanical
stress placed on filter media when fully exposed to the forces of
the washing cycle reduce the filter media life. The outer shield
portions 330 not only provide protection from biological fluid
contamination (e.g., blood, saliva, and cough/sneeze droplets), the
outer shield portions 330 also increase the number of wash cycles
that the underlying particulate air filters 340 can withstand,
extending the life cycle of the respirator 300. The outer shield
portion 330 also enables a simplified cleaning process, including
automated cleaning regimens.
[0083] The particulate air filter 340 may be similar to the first
particulate air filter 141 of FIG. 3. The filter rim 345 is
configured to hold at least one particulate air filter 340. In some
embodiments, the filter rim 345 is adapted to hold a pair of
particulate air filters 340, one on the left side of the mask 310
and another on the right side of the mask 310. In some embodiments,
the filter rim 345 is adapted to encapsulate four particulate air
filters 340, a top-left, a top-right, a bottom-left, and a
bottom-right particulate air filter. Other configurations of the
filters are possible.
[0084] The filter rim 345 and the frame 320 may be molded
separately or overmolded together in one step with one or more
particulate air filters 340 encapsulated therein. In certain
embodiments, each particulate air filter 340 includes a
polytetrafluoroethylene (PTFE) filter media having at least one
layer of PTFE. In some embodiments, the particulate air filter 340
may include other types of filter media, such as high-efficiency
particulate air (HEPA) filters and ultra-low particulate air (ULPA)
filters. Other types of filter media such as microglass may be used
without departing from the scope hereof, although a non-shedding
filter media is preferable for durability.
[0085] Similar to the first and second particulate air filters 141,
142, the particulate air filter 340 is adapted to exceed NIOSH
requirements for the N95 filter class after performing numerous
reprocessing protocols. The thickness of the particulate air filter
340 is adapted to be thin enough for improved ventilation, lower
breathing resistance, and speech intelligibility.
[0086] The optional pair of inner shields 335 provide a washable,
flexible insert (e.g., a scrim) that provides a protective surface
covering the pair of particulate air filters 340, respectively. The
optional inner shields 335 extend the life cycle of the respirator
by protecting the filter media during automated cleaning
processes.
[0087] The face seal 350 is similar to the face seal 150 of FIG. 1
and designed to comfortably fit over the wearer's nose and mouth
and form an airtight seal. In certain embodiments, the face seal
350 is made of silicone and is adapted to reduce facial pressure
and discomfort.
[0088] The face seal 350 includes a built-in user seal check
method. The user seal check method is adapted for a wearer of the
respirator 300 to test that the face seal 350 provides a proper
airtight seal. In one embodiment, the pair of outer shield portions
330 are each adapted to be collapsible against a respective
particulate air filter 340, providing a seal against the respective
air filter 340, which allows the user seal test to be performed.
Each outer shield portion 330 is flexible enough to be pushed into
a collapsed configuration to create a seal when needed. The user
then tests the seal by inhaling slightly to confirm a good facial
seal. A flap valve may be included on the mask 310 that is
activated by a push of a finger. The flap valve is normally
slightly open and may be pushed closed with a finger. The user then
tests the seal by inhaling slightly to confirm a good facial
seal.
[0089] The materials used to form the individual components of the
respirator 300 are selected to have bonding compatibility with one
another to ensure a durable bond. For example, the outer shield
portion 330, frame 320, filter rim 345, optional inner shield 335,
and face seal 350 may be made of one or more plastic materials
(e.g., via an injection molding process) that have bonding
compatibility (e.g., for overmolding). Exemplary plastic materials
include but are not limited to silicone, polypropylene,
Thermoplastic Silicone Vulcanizate (TPSiV), polyolefin,
polyphenylsulfone, high-density polyethylene (HDPE), acrylonitrile
butadiene styrene (ABS), acrylic polymethyl methacrylate (acrylic
PMMA), acetal copolymer (POM), polyetheretherketone (PEEK), and/or
polybutylene terephthalate (PBTR).
[0090] In certain embodiments, the strap 360 provides a
single-sized harness made of a single piece of material (e.g., a
silicone material). Alternatively, the strap 360 may include a
two-piece harness, or multiple pieces. The strap 360 may be
available in different sizes to fit different head sizes of the
user. The strap 360 is adapted to avoid the wearer's ears to
prevent hearing impairment. The strap may be coupled to the frame
320 in an integrated or detachable manner.
[0091] Respirator 300 is adapted to be lightweight for improved
comfort, especially for health care workers who may wear a
respirator for long durations. For example, the respirator 300 is
adapted to be lighter than existing elastomeric half-mask
respirators due to the use of lighter materials and fewer
materials. In certain embodiments, the mask weighs between about
3-oz. to about 4-oz, but may weigh more or less. The respirator 300
is adapted to have a shelf life longer than that of existing N95
FFRs, which is typically three to five years, due to the use of
materials that last longer. In certain embodiments, the rated shelf
life of respirator 300 is expected to be greater than fifteen
years.
[0092] Respirator 300 may include an identification tag similar to
the identification tag 105 described above in connection with FIGS.
2 and 3. Respirator 300 may be used with respirator reuse method
200 described above in connection with FIG. 7.
[0093] Advantages provided by embodiments of this disclosure
include the ability to clean, disinfect, and/or sterilize the
respirator 100 as a single unit (including filtration media)
without disassembly using either automated reprocessing
technologies found in health care settings, other occupational
settings, or homes and/or manual field reprocessing protocols
(e.g., OSHA cleaning/disinfection guidance, disinfectant wipe,
etc.) that can be performed regardless of environment. The
materials used to construct the respirator 100 can withstand
temperatures in excess of 50.degree. C. These features foster
reusability especially in the health care setting, which leads to a
lower cost per use and reduced storage requirements compared to
current N95 FFRs used in health care settings. In addition to
filtering particles, gas/vapor absorbents (e.g., carbon) may be
added to the respirator to provide VOC capture.
[0094] Another advantage is an increased lifetime of the respirator
100 compared to FFRs and possibly HMERs and/or their filters, both
in terms of years and total uses, because of the materials selected
and the exclusion of any adhesive bonds between components that are
susceptible to premature failure, especially when repeatedly
subjected to harsh cleaning treatments (e.g., disinfectants,
autoclaving, washer-disinfection, and/or ultrasonic bath). A longer
shelf life also leads to lower costs for the user.
[0095] The reusable respirator 100, 300 is designed to limit
bioburden accumulation by using smooth external surfaces. Because
the mask 110 (and potentially straps 161, 162) is formed from a
single piece of material, creases, bond lines, and other non-smooth
surfaces that typically exist along interfaces between separate
components are mitigated. This provides an advantage for
cleanability, since smooth surfaces are more readily wiped clean.
These smooth surfaces help facilitate the use of a quick field
reprocessing protocol (e.g., disinfectant wipe) that may be applied
for a limited number of reuses (e.g., five or more) between
disinfection processing, which increases the total number of reuses
(e.g., >600 total reuses). Bioburden is also mitigated by
providing an external surface shape with easy accessibility that
reduces entrapment geometry where bioburden can accumulate. All
external surfaces are elastomeric and smooth making manual wiping
effective at removing contamination.
[0096] Other advantages are the use of an integrated tracking
feature (e.g., barcode, QR code, or RFID tag) for monitoring reuse.
The disclosed embodiments do not require exhalation valves, which
are commonly used in FFRs and HMERs and disadvantageously allow the
user to breathe out contaminants, making these devices unacceptable
for use in a sterile environment such as an operating room.
Although the disclosed embodiments are adapted for use in health
care settings, they also provide an improved reusable respirator
option for the general public to protect themselves against
airborne particulate threats.
[0097] Features described above as well as those claimed below may
be combined in various ways without departing from the scope
hereof. The following examples illustrate some possible,
non-limiting combinations:
[0098] (A1) A reusable respiratory protection device includes a
mask adapted for covering a portion of a user's face. The mask
includes a face seal adapted to conform to a user's face around a
nose and a mouth of the user, an outer surface, at least one outer
shield portion formed in the outer surface, and at least one
closeable vent through the at least one outer shield portion. The
reusable respiratory protection device further includes at least
one particulate air filter adapted to filter at least 95% of
airborne particles. The at least one particulate air filter is
housed within the at least one outer shield portion. The at least
one closeable vent is adapted to direct air flow through the outer
surface for filtering by the at least one particulate air filter.
The outer surface is substantially smooth to mitigate bioburden
accumulation and wettable to allow for cleaning, disinfection, or
sterilization thereof. A strap is configured to secure the mask to
the user's face.
[0099] (A2) For the reusable respiratory protection device denoted
as (A1), the device may be configured to be cleaned, disinfected,
and sterilized without disassembly to facilitate reuse.
[0100] (A3) For the reusable respiratory protection device denoted
as (A1) or (A2), the device may be configured to be sterilized by
autoclaving, gamma irradiation, vaporized hydrogen peroxide, or
ethylene oxide.
[0101] (A4) For the reusable respiratory protection device denoted
as any of (A1) through (A3), the device may be configured to be
cleaned, disinfected, or sterilized at temperatures above about
50.degree. C. to facilitate reuse.
[0102] (A5) For the reusable respiratory protection device denoted
as any of (A1) through (A4), the mask may be a unitary structure
formed of a single piece of material.
[0103] (A6) For the reusable respiratory protection device denoted
as any of (A1) through (A5), a protective pocket may be formed in
each of the at least one outer shield portion, the protective
pocket being adapted to protect the at least one particulate air
filter, thereby permitting cleaning and disinfecting of the outer
surface.
[0104] (A7) For the reusable respiratory protection device denoted
as any of (A1) through (A6), the strap and the mask may be made of
a silicone material that is configured to be cleaned, disinfected,
and sterilized to facilitate reuse.
[0105] (A8) For the reusable respiratory protection device denoted
as any of (A1) through (A7), the at least one particulate air
filter may include a filter media having at least one
polytetrafluoroethylene-based layer that is wettable and
sterilizable.
[0106] (A9) For the reusable respiratory protection device denoted
as any of (A1) through (A8), the at least one outer shield portion
may be deformable for enabling closure of the at least one
closeable vent for functional testing of the face seal during
use.
[0107] (A10) For the reusable respiratory protection device denoted
as any of (A1) through (A9), the at least one outer shield portion
may form a gap between the outer surface of the mask and the at
least one particulate air filter that extends to the at least one
closeable vent, the gap being adapted to provide ample space for
dispersing flow of air evenly across the surface of the at least
one particulate air filter.
[0108] (A11) For the reusable respiratory protection device denoted
as any of (A1) through (A10), an inner flexible layer disposed on
an inner surface of the at least one particulate air filter,
wherein the inner flexible layer is located between the at least
one particulate air filter and the user during use.
[0109] (A12) For the reusable respiratory protection device denoted
as any of (A1) through (A11), an identification tag may be
provided, said identification tag being adapted for scanning with a
scanning device.
[0110] (A13) For the reusable respiratory protection device denoted
as any of (A1) through (A12), the substantially smooth outer
surface may be configured to allow cleaning or disinfecting of the
device while being worn by the user.
[0111] (A14) For the reusable respiratory protection device denoted
as any of (A1) through (A13), the mask may have no exhalation valve
such that the mask is configured to maintain a sterile field in an
environment surrounding the user during use.
[0112] (B1) A reusable respirator includes a unitary mask formed of
a single piece of material adapted for covering a portion of a
user's face. The mask includes a face seal adapted to conform to a
user's face around a nose and a mouth of the user, an outer
surface, a first outer shield portion formed in the outer surface,
a first vent through the first outer shield portion, a second outer
shield portion formed in the outer surface, and a second vent
through the second outer shield portion. A first particulate air
filter, housed within the first outer shield portion, is adapted to
filter at least 95% of airborne particles. A second particulate air
filter, housed within the second outer shield portion, is adapted
to filter at least 95% of airborne particles. The first vent and
the second vent are each adapted to direct air flow to the first
particulate air filter and the second particulate air filter,
respectively. The outer surface of the mask is substantially smooth
to mitigate bioburden accumulation and wettable to allow for
cleaning, disinfection, or sterilization thereof.
[0113] (B2) For the reusable respirator denoted as (B1), the first
outer shield portion may be deformable for enabling closure of the
first vent, and the second outer shield portion may be deformable
for enabling closure of the second vent, such that the first vent
and the second vent are temporarily closeable for functional
testing of the face seal during use.
[0114] (C1) A method for processing a respirator for reuse includes
a) providing a reusable respirator. The reusable respirator
includes a mask adapted for covering a portion of a user's face.
The mask includes a face seal adapted to conform to a user's face
around a nose and a mouth of the user, an outer surface, at least
one outer shield portion formed in the outer surface, and at least
one closeable vent through the at least one outer shield portion.
At least one particulate air filter, housed within the at least one
outer shield portion, is adapted to filter at least 95% of airborne
particles. The at least one closeable vent is adapted to direct air
flow through the outer surface for filtering by the at least one
particulate air filter. The outer surface is substantially smooth
and wettable to allow for disinfection thereof. A strap is
configured to secure the mask to the user's face. The method
further includes b) using the reusable respirator in a field, and
c) performing an extended reprocessing protocol.
[0115] (C2) For the method for processing a respirator denoted as
(C1), the method may comprise performing a quick field reprocessing
protocol a predetermined number of times before step c).
[0116] (C3) For the method for processing a respirator denoted as
any of (C1) through (C2), the respirator may further comprise an
identification tag, and the method may further comprise: scanning
the identification tag to track use or the respirator, processing
of the respirator, or both.
[0117] (C4) For the method for processing a respirator denoted as
any of (C1) through (C3), performing the extended reprocessing
protocol may comprise: sterilizing the reusable respirator without
disassembly.
[0118] It should be appreciated that, while the above disclosure
has been generally directed to the field of respirator masks for
protection from airborne particles such as bacteria and viruses,
embodiments of this disclosure may be directed to other fields and
uses. For example, embodiments of the elastomeric half-mask N95
reusable respirator described herein may be adapted to filter other
types of particulates and to provide different levels of
protection, such as 99% or 99.97% minimum filtration efficiency
(e.g., N99 or N100 filter classes, respectively) or different
classes (P-series, R-series). Additionally, while the respirator
100, 300 is designed for compatibility with health care worker use,
this device may be used by other industry and the general
population and cleaned using a home dishwasher/washing machine or
other suitable methods.
[0119] Although embodiments of this disclosure have been described
with reference to the illustrations in the attached drawing
figures, it is noted that equivalents may be employed and
substitutions made herein without departing from the scope hereof
as recited in the claims.
[0120] Having thus described various embodiments, what is claimed
as new and desired to be protected by Letters Patent includes the
following:
* * * * *
References