US3763497A

US3763497A - Fire sate or burn preventive clothing

Info

Publication number: US3763497A
Application number: US00138732A
Authority: US
Inventors: J Leach
Original assignee: Burlington Industries Inc
Current assignee: BI/MS HOLDINGS I Inc A DE CORP
Priority date: 1971-04-29
Filing date: 1971-04-29
Publication date: 1973-10-09
Anticipated expiration: 1990-10-09

Abstract

A fire-resistant garment is constructed of inner and outer fabric layers which define a region to which a source of noncombustible gas is connected through a valve. The valve is operable either manually or automatically to introduce the gas to this region when fire or heat is encountered. The gas leaks through the porous outer layer to reduce combustion on that layer and also creates an insulating space between the layers. The layers may be made of cotton treated with a fire-resistant material or of noncombustible fibers.

Description

Elite States atent [191 Leach FIRE SATE OR BURN PREVENTIVE CLOTHING [75] Inventor: Jack Leach, Greensboro, N.C.

[73] Assignee: Burlington Industries Inc.,

Greensboro, N.C.

[22] Filed: Apr. 29, 1971 [21] Appl. No.: 138,732

[52] US. Cl. 2/81 [51] Int. Cl... A4ld 00/00 [58] Field of Search 2/81, 83

[56] References Cited UNITED STATES PATENTS 2,0l6,l37 10/1935 Javarmes 2/81 [451 Oct. 9, 1973 2,826,758 3/1958 Kahn 2/81 Primary Examiner-Patrick D. Lawson Attorney-Cushman, Darby & Cushman [5 7 ABSTRACT A fire-resistant garment is constructed of inner and outer fabric layers which define a region to which a source of noncombustible gas is connected through a valve. The valve is operable either manually or automatically to introduce the gas to this region when fire or heat is encountered. The gas leaks through the porous outer layer to reduce combustion on that layer and also creates an insulating space between the layers. The layers may be made of cotton treated with a fire-resistant material or of noncombustible fibers.

21 Claims, 6 Drawing Figures PAIENTEDUCI 9 ms SHIUIW 2 INVENTORS l/ ATTOR N EV S m w E 3. L w 4 WM M a a w 2 w: M P

FIRE SATE OR BURN PREVENTIVE CLOTHING BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to fire-resistant fabric constructions and in particular to burn-preventive garments or portions thereof made from such fabrics.

2. Description of the Prior Art The prevention of fire induced injuries to personnel working in areas where there is a fire'hazard has been often attempted, and a major amount of the effort in this area has been centered upon fireproof garments.

Some examples of known fire-resistant or burnpreventive fabrics are those made from fibers which are themselves fire-resistant, such as specially fabricated nylon fibers which will withstand 50 F. without melting, sold under the trademark Nomex. Other fireresistant fibers are sold under the trademark Kynol. Both of these fibers are essentially non-burning and flame-resistant. However, in the case of fluid fuel fires, even if a garment made from such fibers does not burn, the fluid fuel may seep through the garment and thus expose the wearer to burning.

In addition, it is known to be advantageous in certain circumstances to use a light-weight cotton or cotton blend for a fire-resistant fabric. Since these fabrics burn in the natural state, the prior art teaches their treatment with fire-resistant materials, and while this reduces the propensity of the fabric to burn, it does not keep liquid fuel from seeping through to the undergarment or skin of the wearer and there being ignited. Of course, non-woven fabrics exist which reduce the seeping problem but fire-resistant fabrics of this'type are generally much more expensive than fabrics of the woven type and these fabrics are often uncomfortable to the wearer since they completely inhibit the natural process of evaporation from the wearers skin.

Furthermore, none of the garments referred to above provide any substantial insulation of the wearers body from the heat produced by the fire.

SUMMARY OF THE INVENTION In the view of the disadvantages noted above with respect to the prior art, it is the purpose of this invention to provide a fire-resistant garment of woven material which is particularly resistant to penetration by fluid fuels, which exhibits good insulating properties and which does not unduly interfere with evaporation from the wearers skin. It is a further object of this invention to provide a fire-resistant garment in the form of an inner layer, an outer layer and, in the presence of a fire, an insulating gaseous layer.

The above and other objects are accomplished by the provision of a garment including an inner woven layer of relatively high porosity, an outer woven layer of at least partially porous fabric and means for introducing a noncombustible gas into the region defined between the inner andouter layers. The noncombustible gas seeps through the porous outer layer to provide a noncombustible covering layer and also forms an insulating layer between the inner and outer layers to reduce heat transfer from the fire to the wearers body.

The gas introducing means may be manual or automatic and at least the outer layer of fabric may be treated with a fire-resistant material or may be comprised of an essentially non-burning material.

The fire-resistant garment may be of a simple twolayer fabric construction or a tubular cell-type construction. Preferably the two-layers are permanently connected together at a plurality of points to aid in maintaining a gas space of as uniform thickness as possible, but in some cases it is contemplated that the inner layer may be merely an undergarment which is not permanently attached to the outer layer.

A special requirement of the fire-resistant garment is that it should utilize the gas space between layers to protect the wearer from the intense heat which accompanies a fire. A garment having an inner, and an outer layer separated by fabric-type of insulating layer would, of course, reduce heat transfer from the environment of the wearer. However, such a garment would also reduce heat transfer from the wearer to the environment and thus would be very uncomfortable in warm areas. Further, the bulk and weight of such a garment would interfere with the functioning of the wearer.

In some circumstances the inner layer may be eliminated. In these cases the gas would form a region between the outer layer and the wearer's body.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a rear view of a first embodiment of a fireresistant garment in its uninflated state;

FIG. 2 is a side view of the garment of FIG. 1 in which the garment is shown in its inflated state, the degree of inflation being exaggerated for purposes of illustration;

FIG. 3 is a fragmentary sectional view, on an enlarged scale, of a portion of FIG. 2;

FIG. 4 is a rear view of a second embodiment of a fire-resistant garment in its uninflated state;

FIG. 5 is a side view of the garment of FIG. 4 in its .inflated state; and

FIG. 6 is a schematization representation of the valve operating system used in the embodiment of FIGS. 4 and 5.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT and if desired it may consist only of a partial garment in the form of a helmet, jacket, trousers or the like.

Attached to the back of garment 10 is a tank 20 containing a supply of a noncombustible gas such as carbon dioxide under greater than atmospheric pressure. The pressure required is not critical and depends upon design criteria which will be discussed in more detail later.

The tank 20 is connected through a valve 22 to a region 28 between an inner layer 24 and an outer layer 26 of the garment. The valve 22 is operated by a ring 30 located within a recess 32 in a wall of the tank 20 such that when one reaches into the recess 32 and grasps and pulls the ring out from the recess, the valve 22 is opened to permit a flow of gas from tank 20 to region 28. By locating the ring 30 within the recess 32; the chances of accidental inflation of the garment are minimized.

FIG. 2 shows the garment in its inflated condition, the inner layer 24 being shown in dashed lines and the outer layer 26 is being shown in solid lines. The amount of inflation may, of course, be varied but it has been shown during testing that an inflation which produces a uniform distance of approximately one-fourth inch between the

layers

24 and 26 produces satisfactory results without producing an overly bulky garment. Such a region 28 may be effected where the inner layer 24 is fitted to the wearer with a comfortable degree of tightness and the outer layer 26 is sized approximately one size larger. In sizing the layers special care is used to insure a uniform spacing between the layers even at the normally tight fitting areas across the shoulders and upper back and across the back of the hips. Usually it will be necessary to attach the layers to each other at a plurality of points, as by means of threads 27.

In FIG. 3 the action of the noncombustible gas during inflation is demonstrated. When the valve 22 is opened, gas flows from the pressure tank through a conduit 23 to the lower pressure region 28. The tank volume and pressure should be such that the region 28 fills rapidly with gas upon opening the valve 22, and if necessary several conduits 23 may be provided to different parts of the garment. The tank volume and pressure should be sufficient in conjunction with the porosity of the outer layer 26 to insure a flow of at least 3 cubic feet per minute (CFM) through layer 26 to the atmosphere during the time interval necessary to extricate the wearer from the fire area. In most cases an upper flow limit of 20 CFM will insure satisfactory operation of the garment 10, although this quantity may vary with the degree of fire hazard which exists.

FIG. 3 shows that the noncombustible gas after seeping through the outer layer 26 forms a non-burning layer 34 adjacent thereto which both cools the outer layer 26 and extinguishes or blows out any flames which may attach themselves to the outer layer 26. The movement of the gas through the outer layer 26 also has the effect of physically blowing non-flaming hot liquid out of the garment or of preventing its penetration through more than the gasoline explosion such as found in racing car accidents or hanger deck fires where flaming fuel may hit the victim.

Moreover, since the region 28 is a dead air space when inflated by noncombustible gas, it forms an effective thermal insulation between the outer and inner layers, and thus the garment protects the wearer against the heat as well as the burning effects of the fire.

Turning now to the second embodiment, one major difference between the garment 36 shown in FIG. 4 and that shown in FIG. 1 is that the latter garment 36 has a tubular cell type of construction. That is, the garment 36 consists of tubular double-walled cells 38 separated from one another by bands 40 at which the inner and outer layers are attached to and in contact with each other. Gas passes from cell to cell by means of tubes 42 which connect all of the cells to the pressurized gas tank 20' through a valve 44. The tubular cells 38, each include a region 28 allows for easier bending at the wearer's joints than does the article of the first embodiment and thus provides superior mobility. In addition, the regions 28 confine the non-combustible gas so as to retard downward movement of heavier than air gas.

The second embodiment also differs from the first in the design of its valve control means. As seen in FIG. 4, the tank 20' and valve 44 form portions of a back pack 46 which also include a valve control means comprising a battery 48, a temperature sensor 50 and a valve operator 52.

As illustrated in FIG. 6 the battery 48 is connected through the temperature sensor 50 of the bimetallic switch type to the valve operator 52 which may be solenoid mechanically connected to the valve 44. When the ambient temperature is below a given level the bimetallic switch will be open and thus the solenoid 52 will not be energized and the battery will experience no current drain. When a fire raises the ambient temperature to a given level, the bimetallic switch will close, the solenoid will be energized to open valve 44 and the pressurized contents of tank 20 will flow to region 28.

The type of fabric from which the outer layer 26 is manufactured is not critical to the invention so long as it is at least partially porous. One particularly suitable construction is a twill weave, because a twill weave permits close control of fabric porosity so that uniform porosity can be provided. The inner layer 24 should have relatively high porosity to permit evaporation of moisture from the skin. When the garment has no glove or foot portions, the ends of the sleeves and trousers portions may be sealed to the wearer's skin with elastic bands with the result that the porosity of the inner layer 24 does not create appreciable leakage of gas from the region between the layers.

In either-of the above described embodiments, the particular type of fabric used should be dependent upon the accessibility of an escape route from the area of fire hazard, i.e., the length of time the material will be exposed to the flame and heat of a fire.

In ordinary cases where the person is working in a relatively open area where a high fire hazard condition exists, both the inner and outer layers of the garment may be woven from cotton or cotton blends. A cotton garment may be treated with a fire resistant material such as n-methylol acrylamide plus triallyl phosphate. Alternatively, the fabrics may be composed of a blend of approximately 50 percent nylon and 50 percent cotton which has heat inhibiting properties and tends to reduce the penetration of heat of the high temperature flash type for what might very well be the crucial few seconds necessary for allowing the person to escape from the area through the exit routes.

Under other conditions where the person is working in a confined area without a ready exit route available, the fabrics should be made from Nomex or blends of Nomex and Kynol fibers which are essentially nonburning and flame-resistant. The use of these fibers or blends thereof, together with the positive gas pressure inside the region 28, will normally prevent heat and flame penetration for a time equal to the time which the gas delivery source can provide gas to the region 28. A limited exit condition would be one that might exist in an Army battle tank or an extremely harzardous industrial area where extra precautions are taken with regard to fire walls, fire doors, and the like where the main thrust of the industrial effort is to prevent propagation of the fire beyond a very limited area or to prevent explosion escape into other more vulnerable areas.

While the above description throughly covers the preferred embodiment many modifications are possible within the scope of the invention.

Thus, for example, the inner layer may be dispensed with, and the region 28 would be the region between layer 26 and the wearers body. Additionally, the area of coverage may be restricted to less than the total area of the wearers body. Moreover, the source of noncombustible gas may be located apart from the wearer and connected to the garment by a flexible tube. Of course, the specific type of valve control means can also be altered; for instance, an optical sensor which would complete a circuit when exposed to light of a certain intensity may replace the sensor 50.

Furthermore, other fire protective equipment such as boots, gloves and helmets can be used with the garment whence the garment itself need not be designed to cover the hands, feet and all but the face portion of the operators head as is shown in the Figures. As an alternative to the back pack and as a quick escape unit, a bottle, containing the inflation gas, can be attached to the waist by any of several harness or sling arrangements. This bottle can be equipped with a quick release valve and orifice to allow immediate release by the suit wearer in the event of a sudden flash fire. The bottle can be loaded with enough CO or other suitable gas for protection for a minimum of 30 seconds. The valve on the bottle can be activated by a slap type release or heat activated unit. For weight distribution more than one bottle may be used. Such an arrangement would be light and allow mobility for users who are actively performing duties which require physical movements.

What is claimed is:

l. A fire-resistant garment comprising, an outer layer of at least partially porous fabric which envelopes at least a portion of the wearers body and means for introducing pressurized noncombustible gas into the region between said outer layer and the wearers body whereby said gas forms a thermally insulating layer and flows through said layer to blow out flame and prevent entry of fluids, said introducing means comprises a source of noncombustible gas, a conduit means connecting said source to said region, valve means disposed within said conduit for controlling gas flow through said conduit, a temperature sensor which produces a signal when it senses a certain temperature and an'operator responsive to the output from said temperature sensor for actuating said valve means to permit gas to flow from said source to said region.

2. A fire-resistant garment comprising an outer layer of at least partially porous fabric which envelopes at least a portion of the wearers body an inner layer of fabric which covers at least a portion of the wearers body and which is enveloped by said outer layer,

and means for introducing pressurized noncombustible between said outer layer and said inner layer whereby said gas forms a thermally insulating layer and flows through said layer to blow out flame and prevent entry of fluids,

said inner and outer layers being arranged together so as to form a plurality of tubular cells, each of which is defined by a region enclosed between said inner and outer layers and adjacent points of contact between said inner and outer layers.

3. The garment claimed in claim 12 wherein passage means connects each tubular cell of said tubular cell arrangement with said introducing means.

4. A fire-resistant garment comprising an outer layer of porous fabric which envelopes the entire portion of the wearer's body except for the front of the head, said fabric having a twill type construction to insure a relatively constant porosity throughout the various portions of the fabric, and means for introducing pressurized noncombustible gas into the region between said outer layer and the wearers body whereby said gas forms a thermally insulating layer and flows through said layer to blow out flame and prevent entry of fluids.

5. The garment claimed in claim 4 wherein said introducing means comprises a source of noncombustible gas, conduit means connecting said source to said region and valve means associated with said conduit for controlling gas flow through said conduit, said valve means being actuable by the wearer for permitting said gas to flow from said source to said region.

6. The garment claimed in claim 4 wherein at least the outer fabric is comprised of an essentially nonburning fabric.

7. The garment claimed in claim 4 further including an inner layer of fabric which covers at least a portion of the wearer's body and is enveloped by said outer layer such that the noncombustible gas is introduced into the region between said outer and inner layers.

8. The garment claimed in claim 17 wherein the inner and outer layers are arranged together in a tubular cell type of construction.

.9. The garment of claim 7 wherein the inner and outer layers are connected together at a plurality of points by threads.

10. A fire-resistant garment comprising an outer layer of at least partially porous cotton fabric treated with a fire-resistant material which envelopes the entire portion of the wearers body except for the front. of the head and means for introducing pressurized noncombustible gas into the region between said outer layer and the wearers body whereby said gas forms a thermally insulating layer and flows through said layer to blow out flame and prevent entry of fluids.

ill. The garment claimed in claim 10, wherein said introducing means comprises a source of noncombustible gas, conduit means connecting said source to said region and valve means associated with said conduit for controlling gas flow through said conduit, said valve means being actuable by the wearer for permitting said gas to flow from said source to said region.

112. The garment claimed in claim 10, wherein at least the outer fabric is comprised of an essentially nonburning fabric.

13. The garment claimed in claim 10, further including an inner layer of fabric which covers at least a portion of the wearers body and is enveloped by said outer layer such that the noncombustible gas is introduced into the region between said outer and inner layers.

14. The garment claimed in claim 13 wherein the inner and outer layers are arranged together in a tubular cell type of construction.

15. The garment of claim 13, wherein the inner and outer layers are connected together at a plurality of points by threads.

16. A fire-resistant garment comprising an outer layer of at least partially porous fabric comprised of a blend of cotton and nylon which envelopes the entire portion of the wearers body except for the front of the head and means for introducing pressurized noncombustible gas into the region between said outer layer and the wearers body whereby said gas forms a thermally insulating layer and flows through said layer to blow out flame and prevent entry of fluids.

ing an inner layer of fabric which covers at least a portion of the wearers body and is enveloped by said outer layer such that the noncombustible gas is introduced into the region between said outer and inner layers.

20. The garment claimed in claim 19, wherein the inner and outer layers are arranged together in a tubular cell type of construction.

21. The garment of claim 19, wherein the inner and outer layers are connected together at a plurality of points by threads.

* s :u a:

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION t n 3,763,497 Dated October 9, 1973 Inventor(s) Ja-Ck Leach It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Correct title 12 0 read: "FIRE SAFE OR BURN PREVENTIVE CLOTHING" Col. 1, in the Heading: correct title to read:

"FIRE SAFE QR BURN PREVENTIVE CLOTHING" Col. 1, line 16 change "50F" to -+5ooF--.

Signed anq sealed this Zlet day of May 197E.

(SEAL) Attest:

EDWAIQJ I LFLETUIIEII, Jli. C MARSHALL DANI'J Attest'lng; Officer Commissioner of Patents FORM PO-IOSO (10-69) USCOMM-DC 60376-P69

Claims

1. A fire-resistant garment comprising, an outer layer of at least partially porous fabric which envelopes at least a portion of the wearer''s body and means for introducing pressurized noncombustible gas into the region between said outer layer and the wearer''s body whereby said gas forms a thermally insulating layer and flows through said layer to blow out flame and prevent entry of fluids, said introducing means comprises a source of noncombustible gas, a conduit means connecting said source to said region, valve means disposed within said conduit for controlling gas flow through said conduit, a temperature sensor which produces a signal when it senses a certain temperature and an operator responsive to the output from said temperature sensor for actuating said valve means to permit gas to flow from said source to said region.

2. A fire-resistant garment comprising an outer layer of at least partially porous fabric which envelopes at least a portion of the wearer''s body an inner layer of fabric which covers at least a portion of the wearer''s body and which is enveloped by said outer layer, and means for introducing pressurized noncombustible between said outer layer and said inner layer whereby said gas forms a thermally insulating layer and flows through said layer to blow out flame and prevent entry of fluids, said inner and outer layers being arranged together so as to form a plurality of tubular cells, each of which is defined by a region enclosed between said inner and outer layers and adjacent points of contact between said inner and outer layers.

4. A fire-resistant garment comprising an outer layer of porous fabric which envelopes the entire portion of the wearer''s body except for the front of the head, said fabric having a twill type construction to insure a relatively constant porosity throughout the various portions of the fabric, and means for introducing pressurized noncombustible gas into the region between said outer layer and the wearer''s body whereby said gas forms a thermally insulating layer and flows through said layer to blow out flame and prevent entry of fluids.

6. The garment claimed in claim 4 wherein at least the outer fabric is comprised of an essentially non-burning fabric.

7. The garment claimed in claim 4 further including an inner layer of fabric which covers at least a portion of the wearer''s body and is enveloped by said outer layer such that the noncombustible gas is introduced into the region between said outer and inner layers.

8. The garment claimed in claim 7 wherein the inner and outer layers are arranged together in a tubular cell type of construction.

9. The garment of claim 7 wherein the inner and outer layers are connected together at a plurality of points by threads.

10. A fire-resistant garment comprising an outer layer of at least partially porous cotton fabric treated with a fire-resistant material which envelopes the entire portion of the wearer''s body except for the front of the head and means for introducing pressurized noncombustible gas into the region between said outer layer and the wearer''s body whereby said gas forms a thermally insulating layer and flows through said layer to blow out flame and prevent entry of fluids.

11. The garment claimed in claim 10, wherein said introducing means comprises a source of noncombustible gas, conduit means connecting said Source to said region and valve means associated with said conduit for controlling gas flow through said conduit, said valve means being actuable by the wearer for permitting said gas to flow from said source to said region.

12. The garment claimed in claim 10, wherein at least the outer fabric is comprised of an essentially non-burning fabric.

13. The garment claimed in claim 10, further including an inner layer of fabric which covers at least a portion of the wearer''s body and is enveloped by said outer layer such that the noncombustible gas is introduced into the region between said outer and inner layers.

16. A fire-resistant garment comprising an outer layer of at least partially porous fabric comprised of a blend of cotton and nylon which envelopes the entire portion of the wearer''s body except for the front of the head and means for introducing pressurized noncombustible gas into the region between said outer layer and the wearer''s body whereby said gas forms a thermally insulating layer and flows through said layer to blow out flame and prevent entry of fluids.

17. The garment claimed in claim 16 wherein said introducing means comprises a source of noncombustible gas, conduit means connecting said source to said region and valve means associated with said conduit for controlling gas flow through said conduit, said valve means being actuable by the wearer for permitting said gas to flow from said source to said region.

18. The garment claimed in claim 16 wherein at least the outer fabric is comprised of an essentially non-burning fabric.

19. The garment claimed in claim 16 further including an inner layer of fabric which covers at least a portion of the wearer''s body and is enveloped by said outer layer such that the noncombustible gas is introduced into the region between said outer and inner layers.