Patent Application
20060283455
Respirator hoods are used for respiratory protection and to keep a worker's face, head, and hair free from contamination. Respirator hoods reduce the risk of skin absorption of chemicals. Respirator hoods provide the advantage of covering the entire face and head of a worker, as small respirator devices for the face do not work for people who have facial hair, abnormally sized facial features, or other features that may increase the difficulty of achieving a proper seal around the mouth and nose of the worker. Conversely, full body respirator suits are bulky and cumbersome, often interfering with the movement of the wearer. Further, The cost associated with full body suits detracts from their use where a hood will provide adequate protection.
Respirator hoods cover the head and neck of a wearer. A shroud portion can be draped around the shoulders of a wearer to provide a seal about the person. Further, an additional inner shroud may be tucked into the other garments of the wearer to provide additional protection. Typically, the hood does not provide hit impact protection. Respirator hoods are often made to be flexible. Air is typically supplied into the hood via a hose attached to the front or back. Such respirator hoods are available from many manufacturers, including Minnesota Mining and Manufacturing Company of St. Paul, Minn. The hoods are typically made from a non-woven material having a polymeric coating on the surface. Hoods can also be made from paper, cloth, or additional polymers. Often, the material chosen for the hood prevents the flow of fluids through the material.
In most cases, at least a portion of the hood is transparent. This transparent portion is typically located in an area that will allow the wearer to view the surrounding environment. The hood provides upper body protection against splash hazards, as well as provides the wearer with a field of vision. Respirator hoods may be used in combination with head gear, such as a head suspension or a hard cap. The head suspension or hard cap supports the hood on the head of the wearer and establishes at least a minimal space between the face of the wearer and the hood. The hood may be attached to the head gear in a detachable manner.
The structure of the hard cap may add some definition to the shape of the hood. Even with either a hard cap or a head suspension inserted in the hood, the material of the hood may be sufficiently flexible to allow a wearer access in and out of tight areas that would not be possible for the wearer to observe if the hood was of an inflexible construction. Due to this flexibility of the hood material, hoods often contain creases in the line of vision of the wearer which may impair the vision of the wearer at times.
In one embodiment, a respirator hood assembly comprises a pliable hood including a transparent viewing area and a removable stiffening support structure mountable within an interior of the hood, wherein the support structure draws taut the pliable hood to inhibit the formation of creases in the transparent viewing area.
In another embodiment, the invention is an improvement for a respirator hood assembly having a gas impermeable hood made of a flexible material, the material of the gas impermeable hood having a transparent viewing area, a filtered air inlet to receive breathable air into the hood, at least one check valve for facilitating the exhausting of gas from the hood, and a portion for securing the hood about a head of a wearer. The improvement comprises a removable stiffening support structure attached within an interior of the hood, the support structure being sufficiently rigid to maintain the hood in an expanded upright position and to draw taut the transparent viewing area to enhance wearer viewability therethrough.
In another embodiment, a respirator hood assembly comprises a flexible hood structure having a first condition wherein the hood structure is collapsed for storage and transport and a second condition wherein the hood structure is expanded for respiratory use. The respirator hood assembly also comprises a removable stiffening support structure for the hood structure which, when attached to the hood structure, places the hood structure in the second condition whereby at least a front portion of the hood structure including a transparent viewing area and sides of the hood structure are drawn taut, and means for attaching the removable stiffening support structure to the flexible hood structure.
In another embodiment, the invention is a method of using a respirator hood assembly to protect a wearer from a respiratory hazard. A flexible hood comprising a filtered air inlet, an exhaust system including at least one check valve, and a transparent viewing area, wherein the flexible hood contains an opening for insertion of a head of a body of the wearer is provided. A removable stiffening support structure is removably disposing within an interior of the hood to create a stiffened hood assembly. The stiffened hood assembly is placed about the head of the body of the wearer, and sealed to inhibit the respiratory hazard from entering the interior of the hood assembly.
The above summary of the present invention is not intended to describe each disclosed embodiment or every implementation of the present invention. The figures and the detailed description which follow more particularly exemplify illustrative embodiments.
The present invention is further explained with reference to the drawing figures, wherein like structures are referred to by like numbers throughout the several views.
While the above-identified drawings set forth multiple embodiments of the present invention, other embodiments are also contemplated, as noted in the discussion. In all cases, this disclosure presents the present invention by way of representation and not limitation. It should be understood that numerous other modifications and embodiments can be devised by those skilled in the art which fall within the scope and spirit of the principles of this invention.
“draws taut” means pulled or drawn tight, not slack.
“expanded upright position” means the shape taken by the respirator hood upon insertion of the removable support structure.
“optical properties” means a characteristic, trait, or capability relating to sight as well as characteristics or capabilities relating to the protection of the eyes.
“removable stiffening support structure” means an insert capable of manipulation for insertion and extraction into the respirator hood which adds structure to the respirator hood and draws taut the outer skin layer.
“stiffened hood assembly” means the respirator hood with an insert which reinforces the hood material and makes the sidewall more difficult to move, deform, or bend.
“transparent viewing area” means the portion of the respirator hood capable of transmitting light so that objects or images of the environment are visible to the wearer.
The respirator hood 14 comprises an upper portion 12, and a lower portion 16 including a shroud 18. In the embodiment illustrated, the hood 14 is comprised of an outer skin layer 19 of a gas impervious material. For example, the outer skin layer 19 of the hood 14 may be constructed of a 0.5 mm thick sheet of polyurethane. The hood material is chemical resistant yet environmentally friendly. Other polymers, including polyvinyl chloride (PVC), or coated fabrics, are also used in the construction of such respirator hoods. As illustrated, the hood 14 is transparent. In alternate embodiments, hood 14 may contain a non-transparent, opaque, or colored portion with a transparent visor portion which allows the wearer visibility through a portion of the outer layer skin 19 of the hood 14.
In
The shroud 18 may be constructed from the same or similar flexible, gas impervious material. The shroud 18 need not be transparent. The shroud acts to cover the neck and shoulder portions the body of the wearer and typically includes structure for inhibiting air from entering the interior of the hood 14. The hood and shroud are connected via a seam 26, which may be a heat-sealed seam or other similar permanent attachment similar to seam 24. The shroud 18 contains an opening 27 which allows the head of a wearer to be inserted into the hood 14.
The hood 14 also includes one or more one-way valves 28. Each one-way valve 28 allows air from the interior of the hood 14 to escape while preventing the outside air from entering the interior of the hood 14. The hood 14 also contains an air inlet 30. Typically, the air inlet 30 is connected to a hose (not shown) that runs to a filtering system (not shown) which filters the outside air and transfers the filtered air to the interior of the hood 14. This prevents the wearer from coming in contact with the outside air, which may be unsuitable for unfiltered breathing.
Because the hood 14 is made of a flexible material, the outer skin layer 19 of the hood 14 is allowed to flex which creates folds, undulations, and creases 32 within the hood 14. When disposed within that portion of the hood 14 which serves as a viewing area 36 for a wearer, the creases 32 create visual distortions for the wearer, as well as create physical distractions by allowing the hood 14 to come in contact with the face or head of the wearer. The viewing area 36 extends across the front portion 14a and in many cases at least into the side portions 14b and 14c thereof.
In one embodiment, insert 34 is a sheet of polyethylene terephthalate glycol (PETG) having a thickness of 0.75 mm. Alternatively, insert 34 is constructed from a sheet of polycarbonate, acetate, or a crystalline polymer or similar material. Insert 34 is sufficiently flexible that it is capable of being deformed for insertion into the hood assembly 10. The flexibility of the insert 34 is varied relative to the flexibility of the outer skin layer 19 of the hood 14 to obtain a desired balance between flexibility and stiffness of the hood assembly 10. For instance, hood assembly 10 stiffness can be adjusted or regulated by varying the ratio of the thickness of the insert 34 to the thickness of the outer skin layer 19 of the hood 14, and/or by varying the relative materials. In one embodiment, the thickness of the insert 34 is one and one-half times the thickness of the outer skin layer 19. As can be seen when comparing
In the illustrated embodiment, insert 34 also contains apertures 48 which allow for placement of the insert 34 around the one-way valves 28 of the hood 14. In the embodiment illustrated in
Insert 34 is manufactured as a flat sheet. The sheet is pliable and flexible to allow the sheet to be rolled into a generally cylindrical or conical shape for insertion into the interior of the hood 14. As illustrated in
The hard cap 60 contains a concave bottom surface for reception of the head of a wearer. The concave bottom surface is generally centrally located within the top 20 of the hood 14. Thus, with the insert 34 installed and the hood 14 placed on the head of a wearer, the hard cap 60 positions the hood 14 about the head of the wearer, leaving space between the face and back of the head of the wearer and the interior of the hood 14. Thus, the material of the side wall 22 of the hood 14 is inhibited from coming in contact with the head of the wearer, so as not to distract or irritate the wearer.
Insert 80 contains a series of fasteners 86 about the upper and lower parallel sides. In the embodiment illustrated in
Insert 80 also contains a visor portion 90 as defined by perimeter 88. In this embodiment, the visor portion 90 may be an aperture in the insert 80, or may have different optical properties than that of the rest of insert 80. For example, visor portion 90 may be tinted, polarized, magnify, be UV resistant, or a harder material for shielding the eyes of the wearer from airborne debris, or similar properties. The visor portion 90 may also include a structural pattern on the surface such as a micro-replicated surface. Additionally, the visor may be coated with another substance, including a lubricating liquid or silicon prior to installation into the hood assembly 10. Such a micro-replicated surface or lubricant inhibits the formation of air pockets on the contact surface between the visor portion 10 and the inner surface of side wall 22 of hood 14.
The insert 80, including visor portion 90, may contain a coating on the inner surface, that is, the surface closest to the wearer. The coating can comprise or further aid optical properties. For example, the coating may be an antifogging agent, or a scratch resistant coating to prevent items of the wearer (piercings, eyeglasses, etc.) from marring the surface to create visual obstacles for the wearer. Similarly, visor portion 90 may be formed from a transparent crystalline polymer, while the rest of insert 80 contains a differing optical property (such as being tinted or opaque). Alternately, the insert 80 may be a single sheet containing the same optical properties with no discernable perimeter 88 of a visor portion 90.
In addition to the tabs on insert 34 and fasteners on insert 80, the insert of the present inventive hood assembly could be secured to the hood by any of common fastening means or combination of different fastening means for attaching the materials of the hood and insert. The fasteners could be magnets, and the hood would contain ferrous inserts for the magnets to attract and secure the insert to the hood. The hood may contain pockets or slots while the insert contains corresponding structures such as tabs as previously described, or the insert may be sized so that one or more tabs on one side are received in like slots on the other side of the insert. Alternately, one or more strips of hook tape may be attached near the top edge and bottom edge of an insert, and corresponding loop tape strips attached to the inner surface of the side wall of the hood (or vice versa). Upon insertion and placement of insert into the appropriate area of the interior of the hood, each opposed pair of the hook-and-loop tape strips are pressed together to secure the insert in place. An insert can also be secured by sewing or lacing the hood to he insert using a heavy gage thread. A repositionable pressure sensitive adhesive may be applied to the outer perimeter of an insert so that upon placement of the insert within the hood, the wearer presses the hood and insert together to activate the adhesive. The term “repositionable” means that the insert containing the adhesive can be adhered to and removed from a clean solid surface at least two times without substantially losing tack. Similarly, the material of the hood may be designed and fabricated to contain a static sling film that will secure an insert upon contact with the interior of the side wall of the hood.
Inserts 34 and 80 are removable from hood 14. This creates the advantage, with the insert removed, of increased flexibility of the hood 14 so that it can fit into more areas than if it was a rigid hood or was supported as a more rigid structure by the inventive insert structure. Also, with the insert removed, the hood can be collapsed and stored relatively flat until it is required for use (and the insert can be stored in its flattened state as well). When a stiffened hood is required, the insert may again be inserted and secured relative to the hood 14, assuming the configuration shown in
As was disclosed previously, a hood with the insert in the embodiment of
Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.
