Patent Description:
Patent document number <CIT> describes an encapsulated protective suit having an external air flow hose and comprising a skin, a filter incorporated in the skin of the protective suit, and a seal, wherein when the seal is intact, air does not flow through the filter.

Patent document number <CIT> describes a personal protective ensemble including a sealed suit having at least one area intended to enclose the wearer's head. The suit is equipped with connection means intended to be connected to a pressurized air source. The ensemble includes a protective device having a sealed hood which, arranged underneath the sealed suit, is equipped firstly with means for feeding air to the hood volume and connected to the connection means of the suit, and secondly with means for supplying outside air to the suit via an air intake that is shut and can be opened, arranged in the suit, filtering means and a mouthpiece.

Patent document number <CIT> describes a respirator hood designed to fit over and around the head of a wearer. The respirator hood includes a substantially transparent lens received in a front opening of the hood. An inflatable neck cuff is positioned near a lower portion of the hood and substantially circumscribes an opening through which the wearer inserts his head, with the inflatable neck cuff being supplied by an air source and inflated so as to exert a sealing pressure against the neck of the wearer and to prevent the hood from rising up relative to the head of the wearer. The respirator hood also includes one or more overhead channels which define an air delivery path from the air source over the head of the wearer to the interior of the lens and downwardly across the face of the wearer.

The present invention in its various aspects is as set out in the appended claims. The invention is set out in claim <NUM>, while the preferred aspects are set out in the the dependent claims.

The features of the claims will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings.

It should be understood at the outset that although illustrative implementations of one or more embodiments are illustrated below, the disclosed systems and methods may be implemented using any number of techniques, whether currently known or not yet in existence. The term embodiments is to be understood as meaning that features may still be combined rather than illustrating mutually exclusive features of the invention. The disclosure is not necessarily limited to the illustrative implementations, drawings, and techniques illustrated below.

Known protective suits may have one or more shortcomings. Some protective suits have only a single primary source of breathable air, for example a source of breathable air provided by coupling to a breathable air manifold or provided by a powered air purifying respirator (PAPR) and do not provide an emergency air source for use when the primary source of breathable air fails. When a sole source of air fails, CO<NUM> levels may increase to dangerous levels inside the protective suit before a user of the suit can evacuate the hazardous air environment to a safe air environment. Other protective suits have a primary and an emergency source of breathable air but are fully encapsulated, full body length suits and hence possibly unnecessarily confining to worker freedom of motion and/or unnecessarily expensive. What is needed is a ventilated hood that provides both a primary source of breathable air and an emergency source of breathable air, that provides enhanced worker freedom of motion (i.e., gives less encumbrance) relative to a fully encapsulated protective suit, and that is less expensive than a fully encapsulated protective suit. Similarly, a ventilated hood is required which is more easily donned. The present invention addresses the above problems. The present invention is illustrated in the detailed description particularly so.

A ventilated hood is described herein. The ventilated hood may be implemented in a variety of embodiments. The ventilated hood receives a primary supply of breathable air form an external air hose and provides an alternative emergency breathing apparatus that provides an alternative supply of breathable air through a filter. This provides improved safety and reliability, such as whilst also reducing encumbrance. The ventilated hood may be used by a human being working in a work environment that may contain particulate contaminants and/or chemical contaminants that pose a health risk if the contaminants are inhaled by the human being. Without limitation, such environments may include nuclear power plants, nuclear material handling facilities, pharmaceutical manufacturing plants, asbestos removal projects, and others.

In an embodiment, a powered air purifying respirator carried by the human being may provide the primary supply of breathable air through the external air hose to the ventilated hood. Alternatively, a breathable air network may provide taps at different points in a work environment, and the human being may attach the external air hose provided at such a tap to the ventilated hood for supplying air to that hood. If the primary supply of breathable air fails, the human being may employ the emergency breathing apparatus to breathe safely. It is expected that the human, when normal air flow fails, will begin returning to a safe area shortly after the normal air flow source fails, and hence it is contemplated that the emergency breathing apparatus will be used for relatively short time intervals, for example for less than <NUM> minutes, for less than <NUM> minutes, or for less than <NUM> minutes.

Turning now to <FIG>, a first emergency breathing apparatus <NUM> is discussed. In an embodiment, the first emergency breathing apparatus <NUM> comprises a filter <NUM>, a seal <NUM>, a filter coupling <NUM>, a breathing pipe coupling <NUM>, a breathing pipe <NUM>, and a mouth piece <NUM>. It is understood that the first emergency breathing apparatus <NUM> may comprise other components that are not illustrated or described herein. In some contexts the filter <NUM> may be referred to as an air filter. The filter <NUM> may filter particulate matter and/or chemical material. The first emergency breathing apparatus <NUM> and/or the filter <NUM> may be said to be incorporated into a skin <NUM> of a ventilated hood discussed further below. Additionally, the view presented in <FIG> is schematic and not intended to represent relative sizes or scale of the illustrated components. The inside of the ventilated hood is to the right of the skin <NUM> and the outside of the ventilated hood is to the left of the skin <NUM> as illustrated in <FIG>. The skin may be any extended surface that separates between an outside and an inside of the ventilated hood. Preferably, such a skin does not extend beyond that required to form a hood and as such does not normally extend below the torso of a user. The outside may be referred to in some contexts as the exterior of the ventilated hood and the inside of the ventilated hood may be referred to in some contexts as the interior of the ventilated hood. The exterior of the ventilated hood may also be referred to in some contexts as an external environment and/or a contaminated environment, for example an external contaminated work environment. The ventilated hood, in any of the embodiments disclosed herein, can be a single use ventilated hood, a limited use ventilated hood, and/or a reusable ventilated hood.

Under normal operation, that is when the user of the ventilated hood is breathing air provided via an external air hose, the seal <NUM> blocks flow into and out of the filter <NUM>. This blockage by the seal <NUM> contributes to the air-tightness of the ventilated hood (e.g., when a collar of the ventilated hood is inflated by air flow in an external air flow hose <NUM>) and promotes the efficiency of the ventilated hood. When emergency air supply is needed, the seal <NUM> is torn at least partially free of the skin <NUM> and/or free of the filter <NUM>, opening a pathway for air to flow in through the filter <NUM>, through the couplings <NUM>, <NUM>, up the breathing pipe <NUM>, to the mouth piece <NUM>. The portion of the filter <NUM> facing to the left in <FIG> may be referred to as an exterior face or an outside face of the filter <NUM>; the portion of the filter <NUM> facing to the right in <FIG> may referred to as an interior face or an inside face of the filter <NUM>.

In some embodiments, the emergency breathing apparatus <NUM> can pass through an additional crossing <NUM> such as a seal, barrier, or skin between the exterior of the filter <NUM> and the mouth piece <NUM>. The crossing <NUM> can create a seal or substantially seal against the breathing pipe <NUM> to create a barrier. In some embodiments, the crossing <NUM> can be formed of a material used to form the hood and may serve as a structural support rather than being intended to form a seal. When the ventilated hood comprises an inflated collar, as described herein, the crossing <NUM> can represent one or more portions of the inflated collar. This may allow the emergency breathing apparatus <NUM> to be incorporated into a skirt of the ventilated hood and pass through the collar and into an interior of the ventilated hood. This further reduces encumbrance.

In an embodiment, the filter <NUM> may be a pancake type filter. Pancake type filters are known in the art and may take a variety of different forms. In an embodiment, a pancake type filter may be substantially cylindrical in shape where the height of the cylinder is less than the width or diameter of the cylinder. For example, in an embodiment, the height of the cylinder may be less than <NUM>% of the width or diameter of the cylinder. Alternatively, in an embodiment, the height of the cylinder may be less than <NUM>% of the width or diameter of the cylinder. While pancake filters may be generally circular in section, the pancake filter may be polygonal in section or elliptical in section. The filter <NUM> may be a P3 filter. Alternatively, the filter <NUM> may be a P2 filter. Alternatively, in an embodiment, the filter <NUM> may be a P1 filter. By providing interchangeable filter types the usefulness of the ventilated hood is increased across a variety of environments. As is known by one skilled in the art, a P3 filter may filter at least <NUM>% of airborne particles; a P2 filter may filter at least <NUM>% of airborne particles; and a P1 filter may filter at least <NUM>% of airborne particles. In other embodiments, however, the filter <NUM> may be a different filter.

Turning now to <FIG>, further details related to the seal <NUM> and the filter <NUM> are described. In an embodiment, the seal <NUM> is secured in a sealing position by a tearable weld <NUM>. In other embodiments, however, another means may be used to secure the seal <NUM>, for example an adhesive. Tearable welds and non-tearable welds are generally known in the art. Without limitation, a tearable weld may be distinguished as being an attachment or coupling between two structures that yields or releases when a first one of the structures is pulled away from the second structure before either structure is damaged. By contrast, without limitation, a non-tearable weld may be distinguished as being an attachment or coupling between two structures such that damage to one of the structures is likely to occur if a first one of the structures is pulled away from the second structure before the non-tearable weld yields.

When the user of the ventilated hood wishes to use the first emergency breathing apparatus <NUM>, the user may grasp the edge of the seal <NUM> and tear it downwards to breach the seal between the skin <NUM> and/or the filter <NUM> and the seal <NUM>. It is understood that the term seal may be used to refer to the structure seal <NUM> that in part establishes a seal, meaning a barrier, between the exterior and interior of the ventilated hood as well as to refer to the state of the existence of the barrier. When the seal <NUM> blocks flow into and out of the filter <NUM>, the seal established between the seal <NUM> and the skin <NUM> and/or the filter <NUM> may be said to be intact. In an embodiment, the seal <NUM> may also be secured to the skin <NUM> and/or the filter <NUM> by a non-tearable weld <NUM> or other structure. As shown in <FIG>, when the seal <NUM> is torn free from the tearable weld <NUM> to open the first emergency breathing apparatus <NUM>, the non-tearable weld <NUM> may retain the seal <NUM> coupled to the ventilated hood so that the seal <NUM> is not separated. This provides a means for rapidly enabling filter operation, such as in an emergency and is facilitated by being part of a hood rather than a full suit as a lower impediment to quick action and less encumbrance is present. If the seal <NUM> were completely separated, it may fall and create a foreign material incident (FMI) in a contaminated area. In another embodiment, however, the seal <NUM> may not be retained by the non-tearable weld <NUM>.

Turning now to <FIG>, the flow of air using the first emergency breathing apparatus <NUM> is described. As illustrated in <FIG>, the seal <NUM> has been torn free from the tearable weld <NUM> and is retained by the non-tearable weld <NUM>. This limits movement of the seal, which could otherwise migrate to, for example, impede and so encumber the vision of a user. Exterior air flow <NUM> enters the filter <NUM>, breathing pipe air flow <NUM> proceeds through the breathing pipe <NUM> to the mouth piece <NUM> where emergency filtered air flow <NUM> is breathed by the user <NUM>. The exhaled air flow <NUM> escapes from the mouth piece <NUM> either through an outflow valve or through user control of exhaled air. In an embodiment, a one-way air flow valve (not shown) may be incorporated in the first emergency breathing apparatus <NUM> to permit flow through the filter <NUM> from the outside to the inside, as illustrated in <FIG>, and to substantially block flow through the filter <NUM> from the inside of the ventilated hood to the outside of the ventilated hood. The view presented in <FIG> is schematic and not intended to represent relative sizes or scale of the illustrated components.

Turning now to <FIG>, a second emergency breathing apparatus <NUM> of the present invention is described. Some of the features of the second emergency breathing apparatus <NUM> are substantially similar to those of the first emergency breathing apparatus <NUM> described above. The view presented in <FIG> is schematic and not intended to represent relative sizes or scale of the illustrated components.

The filter <NUM> used in the second emergency breathing apparatus <NUM> may be a moisture laden or moisture bearing filter. The principle of operation of the filter <NUM> used in the second breathing apparatus <NUM> may depend upon the moisture contained within the filter <NUM>. For example, the filter <NUM> in the second breathing apparatus <NUM> may be a tritium filter. As is known to those skilled in the art, tritium is a radioactive isotope of hydrogen that may be encountered in nuclear reactor work environments and poses significant health risks to workers who may inhale tritium. To assure that the filter <NUM> in the second breathing apparatus <NUM> remains moist, the filter <NUM> may be sealed in the ventilated hood on both an exterior and interior of the ventilated hood. Thus, the seal <NUM> may be coupled to the exterior of the skin <NUM> and/or the exterior of the filter <NUM>, and the seal <NUM> may be coupled to the interior of the skin <NUM> and/or the interior of the filter <NUM>.

Before donning the ventilated hood, a user may tear down the seal <NUM>. After tearing down the seal <NUM>, the user may couple the filter air coupler 122a with the breathing pipe air coupler 122b. Then when the user needs to employ the second emergency breathing apparatus <NUM>, for example in emergency breathing situation, the user tears open the seal <NUM> and breathes through the mouthpiece <NUM> as described above with reference to the first emergency breathing apparatus <NUM>. In an embodiment, a one-way air flow valve (not shown) may be incorporated in the second emergency breathing apparatus <NUM> to permit flow through the filter <NUM> from the outside of the ventilated hood to the inside of the ventilated hood, and to substantially block flow through the filter <NUM> from the inside of the ventilated hood to the outside of the ventilated hood.

It is understood that the above teachings can be applied to ventilated hoods of various form factors. In general, the ventilated hood has a skin that provides a barrier between the outside, possibly contaminated environment, and an inside where the human wearer, a user, of the protective suit would otherwise be vulnerable to the subject contaminants. The contaminants may be radioactive particulate matter, chemical particulate matter, asbestos, or other contaminants. As examples and without limitation, the work environment in which ventilated hoods may desirably be used may be nuclear power plants, radioactive materials handling facilities (e.g., medical materials such as radioactive sources for diagnostic imaging and radioactive materials for cancer treatments, radioactive sources for smoke detection), pharmaceutical production plants, chemical factories, oil refineries, asbestos removal projects, and others. In some cases, the contaminants may be gases or air borne liquids (e.g., aerosols).

The ventilated hood may be composed partly of ordinary clothing and partly of a breathing apparatus that encloses the human's head. For example, the ventilated hood may be composed of ordinary shoes, ordinary socks, ordinary pants, ordinary shirt, and a breathing hood that covers the head and comprises a cowl that extends down over the shoulders and chest. The ventilated hood may be composed of ordinary shoes, ordinary socks, a jump suit or overall having leg cuffs that secure closely at the ankles or lower calves and a breathing hood. The collar feature of the present invention allows an interface between such garments and the protective hood that reduces the risk of contamination inside the hood.

Some contaminants pose little health hazard on the outside skin of a human being but may be very hazardous when inhaled. For example, alpha particles emit low energy radiation which does not readily penetrate skin. Thus, alpha particles on the outside skin of a human being may pose little health risk. These same alpha particles, however, can pose significant long term health risks to human beings when inhaled. For example, inhalation of alpha particles may increase long term risk of developing lung cancer. Managing the risk of worker exposure to alpha particles may focus on reducing or preventing inhalation by the worker of alpha particles and washing alpha particles off of the skin of the human worker and off of the clothing of the human worker.

Turning now to <FIG> and <FIG>, a ventilated hood <NUM> is described. The ventilated hood <NUM> (e.g., a breathing hood) in <FIG> is provided with the air flow hose <NUM> that is connected to a tap of a breathable air network provided in the work environment. The breathable air network provides clean, contaminant free air to the air flow hose <NUM> to be breathed by the human being. The ventilated hood <NUM> in <FIG> is provided with the air flow hose <NUM> that is connected to a powered air purifying respirator (PAPR) device <NUM>. The PAPR device <NUM> may incorporate a filter that filters out contaminants from the ambient air in the work environment before feeding it through the air flow hose <NUM> into the ventilated hood <NUM> to be breathed by the human being. In different work environments, either the configuration of <FIG> or the configuration of <FIG> may be preferred.

The ventilated hood <NUM> comprises a collar <NUM> that is coupled to the air flow hose <NUM> and is configured to inflate in response to the air flow in the air flow hose <NUM>. When inflated, the collar <NUM> impedes and/or reduces infiltration of contaminants from the outside environment into the inside of the ventilated hood <NUM>. In an embodiment, the ventilated hood <NUM> may comprise a one-way exhaust valve (not shown) that allows air to pass from the inside of the ventilated hood <NUM> to the outside environment but blocks passage of air from the outside environment into the inside of the ventilated hood <NUM>. Alternatively, or in addition, the flow of air from the air flow hose <NUM> into the ventilated hood <NUM> may exhaust out through gaps between the ventilated hood <NUM>, the collar <NUM>, and the clothing of the human being. The flow of air from the air flow hose <NUM> may provide a positive pressure differential between the inside of the ventilated hood <NUM> and the exterior of the ventilated hood <NUM>, whereby contaminants may tend to be excluded from casual infiltration inside the ventilated hood <NUM>. For example, in an embodiment, the flow of air from the air flow hose <NUM> may provide a positive pressure differential of more than <NUM>,<NUM> Pascals and less than <NUM>,<NUM> Pascals between the inside of the ventilated hood <NUM> and the exterior of the ventilated hood <NUM>. Such pressures also serve to correctly inflate the collar feature to ensure a balance between pressure applied, such as to a user, and sealing efficiency.

The collar <NUM> may be referred to in some contexts by other equivalent terms such as a baffle or inflatable baffle, a flange or an inflatable flange, a bulkhead or an inflatable bulkhead. When the air flow hose <NUM> is unable to supply breathable air to the ventilated hood <NUM>, for example in an emergency circumstance or when disconnected from a breathable air network to leave the work environment, the collar <NUM> may deflate and may no longer impede infiltration of contaminants from the outside environment into the inside of the ventilated hood <NUM>. This is one reason why the emergency breathing apparatus <NUM>, <NUM> is desirably provided for the ventilated hood <NUM>. Another reason is that CO<NUM> levels may build to a dangerous level within the ventilated hood <NUM> if no alternative source of breathable air is provided. A full-face mask with filter may provide an alternative to the ventilated hood <NUM>, but workers may find the full-face mask to be uncomfortable and distracting in comparison to the ventilated hood <NUM>. The use of the ventilated hood <NUM> may be preferred in a work environment with a moderate to low concentration of contaminants while a full-body protective suit may be preferred in a work environment with high concentration of contaminants. In summary, the collar is preferably configured to both receive incoming air and to leak that air in a controlled manner such that removal of inflating air can deflate the collar and thus avoid potential suffocation, such as, for example, if a secondary air supply is either not present or malfunctions. The leak or outlet is preferably of smaller dimensions than the air inlet.

The ventilated hood <NUM> may be a single use protective device or it may be a limited use protective device. A limited use protective device may be used two times or three times before it is discarded. The ventilated hood <NUM> may be inspected to determine if it is suitable for continued limited use or whether it should be discarded. If the expected contaminants in the work environment are radioactive contaminants, the ventilated hood <NUM> may be inspected with a Geiger counter or with another radiation sensitive measuring device. If the expected contaminants in the work environment are chemicals or asbestos, the ventilated hood <NUM> may be visually inspected by the human user and discarded if it looks visibly dirty.

In an embodiment, the emergency breathing apparatus <NUM>, <NUM> may be removable from the ventilated hood <NUM>. For example, the emergency breathing apparatus <NUM>, <NUM> may be coupled to the ventilated hood <NUM> (e.g., a cowl <NUM> of the ventilated hood <NUM>) with a tearable weld or by an adhesive joint. A human user may exit a contaminated work area and enter a changing room. In the changing room, the human user may activate breathing using the emergency breathing apparatus <NUM>, <NUM>, remove the emergency breathing apparatus <NUM>, <NUM> from the ventilated hood <NUM>, doff (e.g., take off) the ventilated hood <NUM>, discard the doffed ventilated hood <NUM>, and exit the changing room to a clean area. In the clean area, the human user may discard the emergency breathing apparatus <NUM>, <NUM> and begin breathing unfiltered air. It is understood that the changing area may have some low level contamination. In some contexts, the changing room may be referred to as an intermediate changing room or by some other name. The human user may further remove work clothes such as work boots, work gloves, work pants, work shirt, or overalls while in the changing room.

Turning now to <FIG>, further details of the ventilated hood <NUM> are described. In an embodiment, the ventilated hood <NUM> comprises a head enclosure <NUM> having a viewing window <NUM> and the collar <NUM>. The air flow hose <NUM> is coupled to the ventilated hood <NUM> and the collar <NUM> in such a way as to both supply breathable air to the inside of the ventilated hood <NUM> and to cause the collar <NUM> to inflate and impede infiltration of contaminants from the outside environment to the inside of the ventilated hood <NUM>. The collar <NUM>, when inflated in this way, may be said to seal, at least partially, gaps between the head enclosure <NUM> and the neck of the human user of the ventilated hood <NUM>. The head enclosure <NUM> and collar <NUM>, when the collar <NUM> is inflated, completely protect the head from contamination in the outside environment while the body of the human user is unprotected (e.g., unprotected by the ventilated hood <NUM>: the body may be protected from contamination in the outside environment by other articles of clothing such as a work overall, work boots, work gloves and the like). The collar is preferably in the form, when inflate4d, of a toroidal tube connected to the skin and is preferably located proximal to and coaxial with the neck position of a user when wearing the ventilated hood.

The head enclosure <NUM> may comprise opaque material or transparent material. The head enclosure <NUM> may be, for example, at least partly stiff and impact resistant. The viewing window <NUM> preferably provides a transparent window that promotes the human being seeing the exterior of the ventilated hood <NUM>, for example to see a work environment. The viewing window <NUM> may be a plastic material. The viewing window <NUM> may be a flexible plastic material. In an embodiment, the head enclosure <NUM> may comprise polyvinyl chloride (PVC). In an embodiment, the viewing window <NUM> may comprise crystal PVC. Such materials can build a static charge and as such it is particularly useful that the tearable portion of the tearable seal is retained after tearing to avoid adhesion by static charge to the viewing window and thus impeded vision. This is particularly relevant in an emergency when the tearable seal may be used.

In the present invention the ventilated hood <NUM> may further comprise a cowl <NUM> configured to rest on the top of the human being's shoulders and to drape down below the crest of the shoulders, over the chest and over the back of the human being. Suc a cowl is part of the skin along with the head enclosure. In some contexts, the cowl <NUM> may be referred to with other roughly equivalent terms such as apron or cape. The cowl <NUM> may provide protection from splashes, projections (squirting or spraying), and/or spills of contaminants such as chemicals. The cowl <NUM> may comprise PVC or another plastic or rubberized fabric. In an embodiment, the cowl <NUM> may be white or colored. For example, in some nuclear power plants pink color may be used to prompt proper disposal of items that may be deemed contaminated.

The ventilated hood <NUM> further comprises the first emergency breathing apparatus <NUM>, the breathing pipe <NUM>, and the mouth piece <NUM> described above. It is understood that in an embodiment, the ventilated hood <NUM> comprises the second emergency breathing apparatus <NUM> described above rather than the first emergency breathing apparatus <NUM>. In emergency circumstances (e.g., when the air flow hose <NUM> is unable to provide breathable air for any reason), the emergency breathing apparatus <NUM>, <NUM> provides filtered breathable air to the human being. In some circumstances, for example in the changing room as described above, the emergency breathing apparatus <NUM>, <NUM> may provide filtered breathable air to the human being, the user, while he or she is doffing the ventilated hood <NUM>.

The cowl <NUM> and/or the head enclosure <NUM> may be said to comprise a skin of the ventilated hood <NUM>. The emergency breathing apparatus <NUM>, <NUM> may be said to be incorporated into the ventilated hood <NUM>, into the cowl <NUM>, into the head enclosure <NUM>, and/or into the skin of the ventilated hood <NUM>. The emergency breathing apparatus <NUM>, <NUM> may be removable from the cowl <NUM> or from the head enclosure <NUM>.

In <FIG>, the emergency breathing apparatus <NUM> is illustrated located in a front or chest area of the cowl <NUM>, but the emergency breathing apparatus <NUM> may be located in different areas of the ventilated hood <NUM>, for example in a back area of the cowl <NUM>, in a right shoulder top area of the cowl <NUM>, in a left shoulder top area of the cowl <NUM>, or elsewhere. See the above descriptions for further details of the emergency breathing apparatus <NUM>, <NUM>.

The cowl <NUM> may extend any distance down over the chest and back. In an embodiment, the cowl <NUM> may comprise at least partially enclosing sleeves. In such an embodiment, the enclosing sleeves may comprise closures such as buttoned cuffs, draw strings, Velcro closures, and the like, to at least partially seal the sleeves against the arms or hands of the human being. In such an embodiment, the enclosing sleeves may comprise elastic material that automatically pulls the end of the sleeves together to seal at least partially against the arms or hands of the human being. In an embodiment, the cowl <NUM> may comprise draw strings to secure the cowl <NUM> to the torso of a human being. In an embodiment, the cowl <NUM> may comprise elastic material that automatically pulls the edges of the cowl <NUM> close to the torso of the human being.

Turning now to <FIG>, an alternative location of the emergency breathing apparatus <NUM>, <NUM> is described. In an embodiment, the emergency breathing apparatus <NUM>, <NUM>, may be located in a side of the head enclosure <NUM> and the breathing pipe <NUM> may wrap around an interior of the head enclosure <NUM> to be proximate to and accessible to a human mouth for use in emergency breathing scenarios. In an embodiment, the emergency breathing apparatus <NUM>, <NUM> may filter particulate contamination. In an embodiment, the first emergency breathing apparatus <NUM> and/or the second emergency breathing apparatus <NUM> may filter chemical contamination. For example, the filter <NUM> may feature, at least in part, a filter medium that interacts with and bonds chemical contamination thereby removing at least part of the chemical contamination from air passed through the filter <NUM> to the breathing pipe <NUM> to the mouthpiece <NUM> to be breathed by a human being. The filter <NUM> may comprise a charcoal filter medium. In an embodiment, the filter <NUM> may comprise an adsorbent medium. In an embodiment, the filter <NUM> may comprise an absorbent medium.

Turning to <FIG>, an embodiment of the emergency breathing apparatus <NUM>, <NUM> is described as having a different interface for breathing <NUM>. The remainder of the emergency breathing apparatus can be the same as or similar to any of the embodiments disclosed with respect to <FIG>. In this embodiment, the mouthpiece of the interface for breathing 600can be in the form of a facepiece <NUM> that is operable to fit over the nose and mouth of a user. The facepiece <NUM> may comprise a molded material, wherein the edge of the facepiece <NUM> may seal against the user's face whenever the facepiece <NUM> is worn. In some embodiments, a user may hold the facepiece <NUM> against their face by holding a mouthpiece in their mouth. The breathing pipe <NUM> may fit through an opening in the facepiece <NUM>, and may be sealed so that no air can pass into the facepiece <NUM> other than through the breathing tube <NUM> when it is worn by a user.

The facepiece <NUM> may comprise a transparent material. In some embodiments, the facepiece <NUM> may comprise a rigid material. In some embodiments, the facepiece <NUM> may comprise a flexible material. In some embodiments, the facepiece <NUM> may comprise a general shape designed to fit on the face of a user. In some embodiments, the facepiece <NUM> may comprise a customized shape for a specific user. In some embodiments, the facepiece <NUM> may comprise one of a plurality of general shapes or sizes, such as small, medium, and large. In some embodiments, the facepiece <NUM> may comprise a nose clip operable to fit over the nose of a user. In some embodiments, the nose clip may fit tight enough on a user's nose to effectively close the use's nose, thereby allowing the user to only breathe through their mouth. In some embodiments, the facepiece <NUM> may comprise an exhalation valve.

The mouthpiece as described herein can be included within the facepiece <NUM>. In some embodiments, the mouthpiece may comprise one or more elements, such as bite plates, grooves, and/or lips. These elements have the advantage the mouthpiece may thereby fit comfortably in the mouth of a user. In some embodiments, a mouthpiece may not be present and the facepiece <NUM> can be used by being held against the user's face. The facepiece <NUM> may not require any elastic or straps to hold the facepiece <NUM> to the user's face, wherein the mouthpiece held in the user's mouth holds the facepiece against the user's face.

<FIG> illustrates the facepiece <NUM> inside the hood <NUM>. The facepiece <NUM> may be placed on either side of the user's head within the hood <NUM>. When the user dons the hood <NUM>, the facepiece <NUM> can be placed out of the way within the hood <NUM>. The facepiece <NUM> may be accessible to the user such as be grasping the mouthpiece within the facepiece <NUM> with their mouth without having to use their hands.

<FIG> illustrates the hood <NUM> and facepiece <NUM> when the facepiece <NUM> is worn on the user's face. The user may grasp the mouthpiece using their mouth to place the facepiece <NUM> onto their face. The user may bend their neck and shoulders to reach the mouthpiece with their mouth. The user may wish to wear the facepiece <NUM> that is coupled to the filter <NUM>, <NUM> to provide filtered breathing air as described herein. Additionally, when doffing the hood <NUM>, the user may be in an area where exposure to hazardous gases is still possible. Therefore, the user may wear the facepiece <NUM> coupled to the filter <NUM>, <NUM> to provide filtered breathing air until the user can move to a safe area. When the user is doffing the hood <NUM>, the user may remove the filter <NUM>, <NUM> from the hood <NUM> to allow the user to continue wearing the facepiece <NUM> when the suit is removed.

A method of using ventilated hoods as previously described may comprise donning a ventilated hood, where the ventilated hood comprises an external air flow hose, a filter incorporated in the ventilated hood, and a first seal and where when the first seal is intact, air does not flow out through the filter from an interior of the ventilated hood. The method may further comprise, after donning the ventilated hood, breaching the first seal and after breaching the first seal, inhaling air received from the filter. Breaching the first seal may comprise ripping the first seal at least partly free of the ventilated hood. Ripping the first seal may comprise ripping the first seal free of a tearable weld coupling the first seal to the ventilated hood. The ventilated hood may further comprise a second seal, the first seal is coupled to an exterior of the ventilated hood, and the second seal is coupled to an interior of the ventilated hood. The method may further comprise breaching the second seal by ripping the second seal at least partly free of the ventilated hood. The second seal in this instance may be breached before donning the ventilated hood. Alternatively, the second seal may be breached after donning the ventilated hood, for example by reaching with a hand below the cowl <NUM> to grip the second seal and rip it at least partly free of the ventilated hood. Reaching under the ventilated hood to rip the second seal at least partly free of the ventilated hood may be performed at about the time the ventilated hood is donned or at about the time that it is desired to commence inhaling air through the filter. In some cases the method may further comprise tearing the emergency breathing apparatus <NUM>, <NUM> free from the cowl <NUM> or free from the head enclosure <NUM>, for example when doffing the ventilated hood <NUM> in a changing room.

While several embodiments have been provided in the present disclosure, it should be understood that the disclosed systems and methods may be embodied in many other specific forms without departing from the scope of the present disclosure. The present examples are to be considered as illustrative and not restrictive, and the intention is not to be limited to the details given herein. For example, the various elements or components may be combined or integrated in another system or certain features may be omitted or not implemented.

Claim 1:
A ventilated hood (<NUM>), comprising:
an external air flow hose (<NUM>) coupled to the ventilated hood (<NUM>);
an emergency breathing apparatus (<NUM>, <NUM>) comprising a filter (<NUM>) incorporated in the ventilated hood (<NUM>), the filter (<NUM>) having an exterior face and an interior face, where the exterior face of the filter (<NUM>) faces towards an exterior of the ventilated hood (<NUM>) and wherein the interior face of the filter (<NUM>) faces towards an interior of the ventilated hood (<NUM>);
a first seal (<NUM>) coupled to one of the exterior of the ventilated hood (<NUM>) or the exterior face of the filter (<NUM>);
a head enclosure (<NUM>); and
characterized in that
the ventilated hood (<NUM>) further comprises a collar (<NUM>) positioned so as to, in use as a hood (<NUM>), be proximal to the neck of a user and coupled to the external air flow hose (<NUM>) and configured to:
inflate in response to receiving air flow from the external air flow hose (<NUM>) for impeding infiltration of contaminants from an external environment to an interior of the head enclosure (<NUM>) by taking up space between the ventilated hood (<NUM>) and the neck of the user; and
leak the received airflow in a controlled manned such that removal of the received airflow deflates the collar (<NUM>) to avoid suffocation; and
the emergency breathing apparatus (<NUM>, <NUM>) further comprises:
a facepiece (<NUM>) operable to fit over the nose and mouth of the user, wherein the facepiece (<NUM>) includes a mouthpiece (<NUM>) to allow the user to hold the facepiece (<NUM>) against their face, wherein an edge of the facepiece (<NUM>) seals against the face of the user when worn; and
a breathing pipe (<NUM>) passing through an opening in the facepiece (<NUM>), wherein the breathing pipe (<NUM>) is coupled at one end to the filter (<NUM>) and at the other end to the mouthpiece (<NUM>),
wherein the collar (<NUM>) comprises a crossing (<NUM>) configured to allow the breathing pipe (<NUM>) to pass through the collar (<NUM>).