US 3789839 A
A protective hood adapted to surround the head of a person in order to protect him against contact with and inhalation of aerosols and gases and other dangerous substances, the hood consisting of a bag-shaped member made of plastic foil, preferably transparent plastic foil, in which an opening is provided and closed by an inhalation filter, a shrouding member being provided and adapted to surround the hood and press it into contact with the surface of the head of the user, so that the dead space in the hood is decreased, said shrouding member preferably consisting of a hood-shaped, elastic net.
Claims available in
Description (OCR text may contain errors)
United States Patent Lund et a1. 1 1 Feb. 5, 1974  COVERING FOR PROTECTING HEAD AND 2,432,311 12/1947 Hall 128/ 142.6
C OM DANGEROUS AEROSOLS AND 2,821,192 1/1958 Monro 128/1426 GASES 3,033,199 5/1962 Jacobs 128/1427 7 3,327,720 6/1967 Carmony et a1. 2/190 [75) Inventors: Bodil Vibeke ,Ierslev Lund; Frederik 3,521,629 7/1970 Reynolds 128/1427 Chrlsflan Freuchen Luna 3,621,841 1 1/1971 Austin 6! 3i. 128/142] both 01' Hellerup, Denmark Primary Examiner-Jordan Franklin } Asslgnee' gigg gg g Copenhagen Assistant Examiner-Peter Nerbun Attorney, Agent, or Firm-Bucknam and Archer  Filed: June 27, 1972  Appl. No: 266,573  ABSTRACT A protective hood adapted to surround the head of a  Foreign Application Priority Data person in order to protect him against contact with June 29, 1971 Denmark 3212/71 and inhalation of aerosols and gases and other dangerous substances, the hood consisting of a bag-shaped 52 US. Cl. 128/142.7, 2/206 member made of Plastic foil, preferably transparent 51 Int. Cl. A62b 18/04, A42b 1/18 Plastic foil, in which an Opening is provided and closed 581 Field ofSearch..... 2/202, 4, 84, 203, 205, 206, by n, inhalation filt a htqu ine bs being 2 71 3 1 0; 128/1426, 42 7 1466; provided and adapted to surround the hood and press 32 4 46 it into contact with the surface of the head of the user, so that the dead space in the hood is decreased, said 5 References Cited shrouding member preferably consisting of a hood- UNITED STATES PATENTS shaped elastlc 521,9'39 6/1894 Pozdena 128/1427 5 Claims, 8 Drawing Figures x 6 $1 Hy/1,7,, I E /ii: 1
PATENTEUFEB 5W 3.789.839
SHEEI 1 [If 3 PATENTEU 5W4 3.789.839
sum 2 or 3 Fig. 5
COVERING FOR PROTECTING HEAD AND FACE FROM DANGEROUS AEROSOLS AND GASES The invention relates to a covering for protecting head and face against dangerous aerosols and gases, more particularly for protecting civil persons during military operations.
Protective coverings for use in military operations are mainly so-called gas masks which are face masks covering part of the face only, mainly the regions around nose and mouth and usually the eyes. This design ensures that the dead space between the filter of the gas mask and nostrils and mouth of the wearer may be relatively small, which is of essential importance to the use of the mask since there will be an accumulation of carbon dioxide in the said space if this volume is not small in relation to the respiratory ventilation.
Gas masks of the kind generally used are relatively costly and are mainly used by a comparatively small number of persons taking active part in military operations or protective measures. The use of such gas masks requires a certain training and there must therefore be a number of different sizes and possibilites of adjustment requiring time-consuming adaptation which, by the way, is dependent on, say, hairdressing. Ordinary glasses and hearing aids cannot be used directly in combination with gas masks nor is adequate sealing obtainable when the wearer has a beard.
The known gas masks of the aforesaid kind usually occupy a rather large volume when packed in a carrying bag.
There has been found to be a demand for a protective covering which can be worn as a safety outfit by every civil person in a dangerous period, and for this purpose the known gas masks will be less suitable. Such a protective covering will have to be manufactured at a very low cost and be adapted for packing so as to occupy very little space, preferably so that it may be placed in a pocket or a handbag. The protective covering must furthermore be of such design that it may be used for all sizes and forms of heads, including bulky hairdressings and the like, and be applicable by persons wearing glasses or dressings on the head. It must furthermore be possible to use the protection effectively without thorough and repeated instructions or adjustments.
Hood shaped protective coverings as known can only be worn a short period, as the dead space is very large and the inspiration air for the wearer will very quickly include a great amount of expiration air having a great content of CO which causes illness.
The present invention provides a protective covering capable of satisfying the said requirements, and an essential feature of the invention is that the protective covering consists partly of a protective hood of a flexible material difficult to penetrate or impenetrable by dangerous liquids and gases, the said material being preferably transparent plastic foil of such size that it may be pulled over the head and at least part of the neck, the said hood being in addition to the end opening provided with a smaller opening which is closed by an inhalation filter adapted to retain the injurious substances, and partly of such a shrouding member that when arranged on the outer side of the protective hood it presses the said hood against the surface of the head and neck of the user.
It has been found that a covering of such design may afford essential protection against many weapons in the form of liquid, aerosol or gas, and that it can ensure a satisfactory respiration of the user for a certain period. Suitable plastics may form a foil which may provide a certain desired protection against dangerous substances and which may have a suitable resistance to mechanical stresses, and in such a hood it is comparatively easy to insert an effective filter to retain the dangerous substances and permit the passage of an adequate amount of air for respiration. A number of plastic foils having advantageous qualities possess the additional advantage that' they are so transparent that a special window element may be disposed with.
If a protective hood of plastic foil were arranged solely around the head of the user and kept tightly to his neck, there would always be a dead space far in excess of what is permissible so that satisfactory respiration would soon be out of the question. This essential problem is solved by means of the aforesaid shrouding which involves no essential enhancement of the cost or complication of the protective covering. it may readily be provided on the protective hood which is thereby pulled into contact with the head and the face so that the dead space is reduced so much that the respiration is not affected to any appreciable extent.
According to the invention the shrouding member may consist of a hood-formed elastic net formed, for example, of knitted textile material. Such a net can be made at a very low cost; it is of small volume, very light weight and may nevertheless act efficiently to pull the plastic foil hood into tight contact with head and face. Such an elastic shrouding member may be of such design that the area of the mesh openings is considerable compared with the area of the threads, and it constitutes no essential obstruction to the view of the wearer. The advantage obtained is that the shrouding member involves no obstruction to the view of the wearer in any of his orientations.
It will often be convenient to keep the protective hood together around the neck of the wearer by means of an elastic, tape-formed closing member as specified in Claim 4, since it is of paramount importance to ensure sufficient sealing at this place.
Usually it will be found preferable to use a plateformed filter which may consist of a plurality of layers, for example a fibrous material with activated carbon and one or more aerosol filter layers. Such a plateformed filter may, according to the invention, be mounted in a frame of relatively more rigid plastic material which is welded or glued to the edge portion around the smaller opening in the protective hood.
Such a filter may be so formed and arranged that it rests in contact with the bridge of the nose and the chin of the wearer so that a relatively small, flat space is left open between the plate-formed filter and nostrils and mouth, which facilitates the respiration.
In order to make the said space of a very convenient form and size, the filter frame may consist of two sections which in the protection provided form an obtuse angle with each other, their axis of intersection extending from the nose of the user downwards to his chin. As a result the filter fits rather snugly to the face of the user.
In certain cases it may be convenient to provide the protective hood with a special exhalation valve, but generally both inhalation and exhalation will be possible through the same passage, which is provided with an aerosol/gas filter.
The invention will now be described with reference to the drawing, in which:
FIG. 1 shows a protective hood, in diagrammatical front view,
FIG. 2 a shrouding member, viewed from the side in its extended state,
FIG. 3 a section through a filter,
FIG. 4 a front view of a filter,
FIG. 5 a protective covering according to the invention as worn by the user,
FIG. 6 a part of a protective hood, viewed from the side in section,
FIG. 7 the same as FIG. 6 for a modified embodiment of the filter, and
FIG. 8 a front view of a protective hood with divided filter.
The protective hood illustrated in FIG. 1 and denoted by 1 may be manufactured as a bag of plastic foil material, and having a substantially rectangular form in flat condition, the said bag may have a mouth 2 at one end and at the other end a welding seam 3. The bag may have one or two side welding seams. It may also be provided with folds and, on the whole, be made in the same manner as conventional packaging bags of plastic foil. In its side wall the hood has a rectangular opening 4 in which there is attached a plate-formed filter 5.
FIG. 3 shows such a filter which is carried by a frame 6 of rather more rigid plastic material with a flange 7 by means of which the frame is welded to the protective hood 1 around the opening 4. In the frame 6 is provided suitable filter material 8 which, for example, may consist of an outer and an inner aerosol filter and an intermediate layer of fibrous material with activated carbon. The frame 6 may be attached to the protective hood 1 by glueing or welding, and the filter 8 may be glued both to the protective hood and to the frame. At 9 is indicated an adhesion which prevents the passage of air around the filter plate along its edge where it joins the frame. The said adhesion may, however, also be substituted by a moulding process, either by injectinga suitable thermoplastic material'between frame and filter or by moulding the frame as a whole of thermoplastic material around the filter. FIG. 4 is a front view of a filter in frame. A grating 17 serves in the embodiment disclosed to relieve tensional forces in the connection between filter and frame. The grating 17 may either be made together with the frame in a moulding process or consist of a plastic material or a wire netting which is glued or moulded into the frame. A corresponding grating for mechanical relief may be provided on such side of the filter as faces the wearer.
FIG. 2 shows a shrouding member having the form of a net which may be made by knitting of textile yarn and which is denoted by 10. The net takes the form of a hood but can also be a tube open in both ends. Shown in FIG. 2 in its distended state, it may be passed down over the hood without difficulty.
When the protective covering is to be used, the plastic foil hood 1 is passed down over the head into a position in which the filter is arranged outside the region of nose and mouth, leaving an unobstructed view. The lower part of the hood will then be located opposite the neck of the user. The shrouding member 10, which may be attached at one or a few places to the top of the hood, is then pulled down over the hood and somewhat down along the neck of the user where any excessive part of the shrouding member may form folds or rolls.
After the aforesaid operation the shrouding member presses, owing to its elasticity, the hood 1 against the head, face and neck of the user as indicated in FIG. 5. The dangerous space in the protective hood is reduced to a minimum and a certain sealing is provided at the neck so that respiration takes place essentially through the filter.
The plastic foil hood 1 will usually form folds at the neck, at the top of the head and at the throat. The relatively rigid filter in combination with the region around the eyes and the forehead of the user will, however, prevent the formation of actual folds in front of the eyes.
When the shrouding member has been mounted as described above, the hood may be oriented for optimum position of filter to suit requirements and will give in this condition a certain protection.
FIG. 5 shows an elastic tape-formed closing member 11 arranged around the neck. The said tape provides primarily efficient sealing of the protective hood around the neck and secondly it retains the hood effectively to the head. The tape or band member 11 is preferably provided with an elastic pad-like layer which can press the hood material against the neck of the wearer over its complete periphery in spite of the uneven shape of the neck surface. The band may include a layer of elastic plastic foam material. As will appear from FIG. 5, glasses used by the wearer do not prevent the use of the protective covering according to the invention. As will appear from FIG. 6, the frame 6 may be so formed that it is capable of resting in contact with the bridge of the nose and the chin of the user so that a relatively small space 12 is formed between the filter 8 and the nostrils and mouth of the user.
FIG. 7 shows a special embodiment of a filter in which the frame is divided into two parts 13 and 14 with flanges 15 which are welded together with the foil material of the protective hood 10 between them. In this embodiment the filter has a front wall and a rear wall which is perforated, the front wall consisting, for example, of obliquely disposed lamella-formed wall parts 16. A filter with a frame of equivalent design may also be manufactured by moulding a thermoplastic material around the filter. In this case the frame has a flange for one-sided attachment to the material of the hood.
In the frame 6 or between the frame parts 13 and 14 may be provided a grate-formed element 17 (FIG. 4) so as to form a number of passageways 18 which contain the filter material.
In the embodiment according to FIG. 8 the filter is divided into two sections consisting of two frames 19 and 20 which form an angle of less than and the axis of intersection between the plates of the two frames is denoted by 21 and extends substantially vertically from the bridge of the nose to the chin. In this embodiment the filter will fit relatively snugly to the face despite the relatively large area of the filter plate. The two frames may be connected with material of such flexibility that they adapt themselves to the form of the head as described above and may be folded against each other during storage. As a result, the maximum dimensions of the packed protective unit is substantially reduced.
1. A covering for protecting the head and face against toxic substances dispersed in the air, which comprises a hood made of flexible, gas-proof material and disposed to encompass the head and neck of the wearer, seal means on said hood operable to circumferentially engage the neck of the wearer to seal the hood thereto and thereby prevent entry of toxified air into the volume enclosed by the hood, air filter means connected to said hood for support thereby and operable to filter and detoxify air passing from outside the hood to the inside thereof for breathing by the wearer, and an elastic net shroud disposed in surrounding relation to said hood and for contact with the exterior surface thereof to press said hood against the wearer and thereby minimize the open volume enclosed by the hood, said elastic net shroud extending from said seal means over substantially the entire area of the hood covering the neck and head of the wearer.
2. A covering according to claim 1 wherein said hood is made of transparent plastic foil.
3. A covering according to claim 1 wherein said elastic net shroud is made of knitted textile material.
4. A covering according to claim 1 wherein said air filter means includes a frame connected in sealing relation to said hood.
5. A covering according to claim 4 wherein said frame has two sections disposed at an angle with respect to each other along an axis of intersection positioned to extend generally from the nose of the wearer down to the chin thereof.
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