SHIRT WITH REINFORCED FRONT

Abstract

A fire resistant shirt is described that is constructed from two or more layers of fire resistant fabric strategically located across the front portion of the shirt to protect the torso of the wearer.

Description

FIELD OF THE INVENTION

This invention is directed to a fire resistant shirt having a front that is reinforced to protect the torso of the wearer.

BACKGROUND OF THE INVENTION

Workers in many industries may be subjected to sudden thermal flashes directly toward the front of the workers' bodies. Electrical workers, for example, may experience an electric arc of great thermal intensity. This is particularly damaging to female workers because their brassieres may ignite outright, or the fabric and underwire melt or burn, causing severe injury. The traditional market solution has been to require female employees who are exposed to these types of danger to wear a brassiere made of a fire resistant fabric. This solution is problematic for the employer because such brassieres are expensive and are often difficult to fit and procure. This solution also causes problems for female employees because these brassieres are made from a fabric having fire resistant fibers, which is heavier, stiffer, more uncomfortable, and more cumbersome than a female employee's regular brassiere fabric.

Typical fire resistant shirts have an arc thermal performance value (ATPV) between 4.2 and 5.6 calories per square centimeter. The highest scoring shirts that are presently commercially available are made from a fire resistant fabric sold under the trademark INDURA ULTRA SOFT®, and weighing 7.0 ounces per square yard. This fabric has an ATPV of approximately 8.3 calories per square centimeter, which is desirable for constructing conventional fire resistant shirts. Conventional shirts manufactured from this fabric, however, can be heavy and hot. Heavier clothing, especially clothing made from fire resistant material, tends to trap heat and result in excessive perspiration (which can conduct electricity), heat exhaustion, heat stroke, or other serious medical conditions that affect an employee's judgment and dexterity on the job.

Accordingly, there is a need for a fire resistant shirt with a construction that provides maximum protection, flexibility, comfort and ventilation while still meeting applicable safety standards. There is also a need for such a fire resistant shirt that provides specialized protection to females. There is a further need for a fire resistant shirt that is economical to manufacture. Still further, there is a need for a fire resistant shirt that can be worn without additional garments protecting a wearer's torso. It is to these needs and others that the present invention is directed.

BRIEF SUMMARY OF THE INVENTION

The present invention is directed toward a flame resistant shirt that provides necessary protection for a wearer by using two or more layers of fire resistant fabric strategically located across the front of the shirt. The layers or plies of fabric greatly increase the frontal resistance of the shirt to the thermal effects of an electric arc, and provide significantly more protection than a single ply of fire resistant fabric, with a minimum increase in weight. Two or more plies of fabric used in accordance with the present invention are especially beneficial when applied to the front of the shirt for a number of reasons. For example, accidents involving electric arcs in work situations generally occur while an affected employee is working with his or her hands on a given task, and therefore generally occur in front of the employee. Infrared energy is the primary heat energy resulting from an electric arc. The arc travels in a straight line and generally does not affect the back of a shirt. Also, most employees wear arc-rated gloves that extend to the elbow and often additionally wear full rubber sleeves that extend from the wrists to the top of the shoulders. These rubber sleeves are held in place with a strap that buckles around the back of the shoulders. The gloves and sleeves leave an unprotected zone from the chest to the abdomen of a wearer, leaving a fire resistant shirt as the primary means of protection.

Many arc-rated rubber sleeves and gloves have an ATPV ranging from 25 to 100 calories per square centimeter. Thus, the main purpose for wearing long sleeved shirts under these rubber sleeves and gloves is not for added protection, but rather for the comfort of the wearer. Constructing the sleeves from a lighter weight material best suits this purpose. Accordingly, the sleeves of the shirt of the present invention can be constructed from one or more plies of varying lengths relative to each other, and the one or more plies can comprise varying materials for the comfort and safety needs of the wearer. Likewise, the overall length of the sleeves can vary to enhance the comfort and safety needs of the wearer. An exemplary embodiment of the shirt in accordance with the present invention includes a double layer of fire resistant fabric on the front panels, and sleeves comprised of a single layer of fire resistant fabric, which allows the wearer to have increased dexterity.

Constructing a fire resistant shirt with two or more layers of fire resistant fabric on the front yields greatly increased protection in the chest/abdomen area with greater breathability and reduced heat retention. This construction also provides a manufacturer with the ability to use one or more layers of lighter material in strategic areas on the shirt instead of using a heavier-weight fire resistant fabric to construct the entire shirt. An exemplary embodiment of the shirt in accordance with the present invention comprises a single layer of fire resistant fabric used to construct the sleeves and the rear portion of the shirt. This construction allows for increased heat ventilation of the back and shoulders of the wearer, and reduces the risks associated with heat build-up. Alternatively, a manufacturer can strategically use fabric or material with or without fire resistance in various areas on the shirt that are not likely to encounter a thermal arc.

The shirt in accordance with the present invention facilitates easier enforcement of fire resistant uniform policies, which can be problematic for an employer of both male and female employees. For example, it is difficult to ascertain whether a female employee is wearing a Nomex IIIA® brassiere or whether a male employee wearing a proper undershirt underneath a conventional fire resistant shirt. The shirt of the present invention can bear a distinctive insignia to allow an employer to readily determine the shirt's arc rating, and thus determine whether an employee is compliant with the employer's fire resistant uniform policies.

The benefits of the construction of the shirt extend to numerous other applications, and the exemplary embodiments described herein are in no way intended to be limited solely to shirts for female wearers, nor solely to the type of sewing construction utilized in the attached drawings as being the definitive means of construction. The shirt can be constructed by other joining or sewing methods known in the art, and by other conventional means of adhesion. By way of example, some drawings illustrate a double ply construction that includes the entirety of the front panels, however, the front panels may be constructed of multiple layers of varying lengths to better accommodate job requirements.

In one embodiment, the front panels comprise first plies of fire resistant fabric extending from the shoulder seams of the front panels of the shirt to a terminus at the bottom edge of the front portion of the shirt. Second plies of fire resistant fabric extend from the shoulder seams of the front panels of the shirt to a terminus located above the bottom edge of the front portion of the shirt. This construction can reduce the cost of the shirt, and can further reduce heat retention.

These features, and other features and advantages of the present invention will become more apparent to those of ordinary skill in the relevant art when the following detailed description of the preferred embodiments is read in conjunction with the appended drawings in which like reference numerals represent like components throughout the several views.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front perspective view illustrating an embodiment of a shirt of the present invention.

FIG. 2 is a detailed view from the interior of the shirt at point A of FIG. 1.

FIG. 3 is a detailed view from the interior of the shirt at point B of FIG. 1.

FIG. 4 is a front perspective view illustrating an alternative embodiment of the shirt of the present invention.

FIG. 5 is a detailed view from the exterior of the shirt at point A of FIG. 4.

FIG. 6 is a detailed view from the exterior of the shirt at point B of FIG. 4.

FIG. 7 is a front perspective view of the front portion of an alternative embodiment of a shirt in accordance with the present invention with the interior side of the shirt facing outward, detailing the construction of the front portion of a shirt with two plies having different lengths relative to each other.

FIG. 8 is a front perspective view of another alternative embodiment of a shirt in accordance with the present invention, showing in phantom lines an alternative construction of the front portion of a shirt with two plies having different lengths relative to each other.

FIG. 9 is a front perspective view of another alternative embodiment of a shirt in accordance with the present invention, showing in phantom lines an alternative construction of the front portion of a shirt with two plies having different lengths relative to each other.

DETAILED DESCRIPTION OF THE DRAWINGS

Illustrative embodiments of the shirt according to the present invention are shown in FIGS. 1 through 9. With reference to FIG. 1, a shirt 1 comprises sleeves 2a and 2b, which extend from armholes 3a and 3b. There is a collar 4 formed above a neck opening 5. Shoulder seams 6a and 6b extend from armholes 3a and 3b to the neck opening 5. Left front panel 8 and right front panel 7 are each constructed from two-plies of fire resistant fabric. Plies 7a and 7b (FIGS. 2 and 3) are stitched together at the neck opening 5 and the shoulder seams 6a and 6b, around the armholes 3a and 3b, and optionally have a stitched hem or surged finish at bottom edges 9 and 10. The sleeves 2a and 2b, the collar 4, and the back portion 1b of the shirt are constructed of a single ply of fire resistant fabric. Two plies of fire resistant fabric are applied in the front panels 7 and 8 only where they are needed for the safety of the wearer.

In one embodiment, the front portion 1a of the shirt 1 comprises the top ply 7a and the bottom ply 7b (FIGS. 2 and 3) of fire resistant fabric, each fire resistant fabric ply having an ATPV of greater than 4.2 calories per square centimeter. Neck opening 5 is at the top of the front portion 1a and a sewn hem is along the bottom edges 9 and 10 of the shirt 1. Stitching around the neck opening 5 and along the bottom edges 9 and 10 holds together the two or more plies 7a and 7b of fire resistant fabric, which are otherwise continuously unbonded in order to enhance the fire resistant properties of the shirt 1. The front portion 1a further comprises left front panel 8 and right front panel 7, which are joined together at an overlapping button hole panel 12 and button panel 11. Stitching 12a along the button hole panel 12 and stitching 11a along the button panel 11 holds together the two or more plies 7a and 7b of fabric. The shirt 1 also has a back portion 1b constructed of a single ply of fabric.

Although opposing surface areas of the plies 7a and 7b are stitched together along certain seams, are generally adjacent one another, and are in contact at their opposing faces, the plies 7a and 7b are otherwise continuously unbonded to each other along the surface areas of their opposing faces. The continuously unbonded plies 7a and 7b provide an air space for additional protection to the wearer. Conventional plies that are continuously bonded or bonded over at least a portion of one or more opposing faces, for example using flammable adhesives, rivets, or additional stitching, can create potentially unsafe conditions for the wearer. The continuously unbonded plies 7a and 7b provide the further advantage of an outer layer (ply 7a) that ablates or peels away from the inner layer (ply 7b) when exposed to a thermal arc, thus removing the thermal energy from the shirt and the wearer.

The single ply of fabric of the back portion 1b and sleeves 2a and 2b are preferably constructed of a fire resistant fabric. A “fire resistant fabric” in accordance with the present invention means that the fabric is not only generally fire or flame resistant, but also meets accepted standards applying to garments exposed to electric arcs or flash fires, like NFPA and ASTM standards. As used herein, a “fire resistant fabric” also has an ATPV of equal to or greater than 4.2 calories per square centimeter. Other fabrics commonly used for fashion and outerwear bearing some general degree of “flame resistance” (such as wool or silk, which are known in the art to be incapable of withstanding electric arcs or flash fires) are not “fire resistant fabrics” as the phrase is used herein. Such fashion fabrics (as opposed to fire resistant fabrics for protective clothing) are not suitable to construct the shirt according to the present invention.

In another embodiment of the shirt 1 in accordance with the present invention, the front portion 1a is comprised of at least two unbonded plies 7a and 7b of fire resistant fabric. The bottom edges 9 and 10 of the top ply 7a and bottom ply 7b of the left and right front panels 8 and 9 can be unstitched such that each ply 7a and 7b has an unfinished edge. This construction is especially applicable when the shirt 1 is constructed from a fire resistant knit material, or another fire resistant material that is not prone to fraying. Optionally, ply 7a can be stitched or surged individually at its bottom edge 9 to form a hem or a finished edge. Likewise, and also optionally, ply 7b can be stitched or surged at its bottom edge 10 to form a hem or a finished edge. Alternatively, the top ply 7a and the bottom ply 7b can be stitched together along the bottom edges 9 and 10 such that the plies 7a and 7b are joined to form a hem or a finished edge.

FIG. 2, which is a detailed view from the inside of the shirt 1 taken at point A of FIG. 1, illustrates the bottom ply 7b and the top ply 7a and how the plies 7a and 7b are folded and sewn at stitch line 11a to form a button panel 11.

FIG. 3, which is a detailed view from the inside of the shirt 1 taken at point B of FIG. 1, illustrates the bottom ply 7b and the top ply 7a and how the plies 7a and 7b are folded in preparation for sewing. A button hole panel 12, is applied above the abutted edges of plies 7a and 7b, and sewn thereto along stitch lines 12a. A strip 14 may be inserted within the button hole panel 11 to provide additional bulk and strength, and can be sewn or otherwise bonded in place, and is preferably fire resistant.

FIG. 4 illustrates another embodiment of a shirt 15 in accordance with the present invention. The shirt 15 has sleeves 16a and 16b, which extend from armholes 17a and 17b. A collar 18 is formed above neck opening 19. Shoulder seams 20a and 20b extend from armholes 17a and 17b to the neck opening 19. Front panel 22 is preferably constructed from two or more plies 22a and 22b (FIGS. 5 and 6) of a fire resistant knit fabric. The plies 22a and 22b are stitched together at the neck opening 19, the shoulder seams 20a and 20b, at a bottom edge 21 and around the armholes 17a and 17b. The shirt optionally has a collar opening 23 comprising an overlapping button panel 23a and button hole panel 23b. The plies 22a and 22b are otherwise continuously unbonded about their opposing surface areas. The sleeves 16a and 16b, as well as a back panel 15a are constructed of a single ply of fire resistant fabric. Optionally, ply 22a can be stitched or surged individually along the bottom edge 21 to form a hem or a finished edge. Also optionally, ply 22b can be stitched or surged at the bottom edge 21 to form a hem or a finished edge. Alternatively, the ply 22a and ply 22b can be stitched together along the bottom edge 21 such that the plies 22a and 22b are joined to form a hem, a surged edge, or an unfinished edge.

FIG. 5 is a detailed view of the collar opening 23, taken at point A of FIG. 4. The joining of top ply 22a to bottom ply 22b is illustrated. The top ply 22a and bottom ply 22b are sewn to the collar 18 as shown at stitch line 24.

FIG. 6 is a detailed view of the bottom edge 21, taken at point B of FIG. 4. The joining of top ply 22a to bottom ply 22b is illustrated. The top ply 22a and bottom ply 22b are folded and sewn together along stitch line 25 to form the bottom edge 21.

FIG. 7 is another embodiment of a shirt 101 in accordance with the present invention. The shirt 101 comprises a front portion 101a and a back portion 101b constructed of a fire resistant material, and is shown with the interior facing outward. The shirt 101 further comprises sleeves 102a and 102b, which extend from armholes 103a and 103b. There is a collar 104 formed above the neck opening 105. Shoulder seams 106a and 106b extend from armholes 103a and 103b to neck opening 105. Left front panel 108 and right front panel 107 are constructed from two-plies of fire resistant fabric of different length relative to each other.

In one embodiment, the left and right front panels 108 and 107 each comprise a first ply 107a and 108a of fire resistant fabric extending from the shoulder seams 106a and 106b of the left and right front panels 108 and 107 of the shirt 101 and having lengths that terminate at the bottom edges 109 and 110 of the front portion 101a of the shirt 101. Second plies 107b and 108b of fire resistant fabric extend from the shoulder seams 106a and 106b of the left and right front panels 108 and 107 of the shirt 101 and have a terminus 126 located between the shoulder seams 106a and 106b and the bottom edges 109 and 110 of the front portion 101a of the shirt 101.

In an exemplary embodiment, and as shown in FIG. 7, the terminus 126 of the second plies 107b and 108b of fire resistant fabric is located approximately at or between one half and two-thirds of a distance measured from the bottom edges 109 and 110 of the front portion 101a of the shirt 101 to the bottom of the arm holes 103a and 103b of the left and right front panels 108 and 107 of the shirt 101. In another embodiment, the terminus 126 of the second plies 107b and 108b of fire resistant fabric is located approximately at or between one-quarter and three-quarters of a distance measured from the bottom edges 109 and 110 of the front portion 101a of the shirt 101 to the bottom of the arm holes 103a and 103b of the left and right front panels 108 and 107 of the shirt 101. In a preferred embodiment, the second plies 107b and 108b have a terminus 126 located approximately at or between one-half and one-third of a distance measured from the bottom edges 109 and 110 of the front portion 101a of the shirt 101 to the bottom of the arm holes 103a and 103b of the left and right front panels 108 and 107 of the shirt 101. In another preferred embodiment, a two ply construction extends from shoulder seams 106a and 106b to approximately the “belt line” of the shirt 101, and a single ply construction continues from the terminus 126 to the bottom edges 109 and 110 of the shirt 101. Thus, in this embodiment, the two ply construction is primarily limited to a portion of the shirt 101 that is not typically tucked into a wearer's pants.

In some cases it may be desirable to provide two or more plies of fire resistant fabric in other areas. For example, the terminus 126 of the second plies 107b and 108b can be located approximately two-thirds of the distance from the bottom edges 109 and 110 of the front portion 101a of the shirt 101 to the bottom of the arm holes 103a and 103b of the front portion 101a of the shirt 101. As another example, the terminus 126 of the second plies 107b and 108b can be located adjacent the bottom of the arm holes 103a and 103b of the front portion 101a of the shirt 101 such that the portions of the shirt 101 that would typically contact a female wearer's brassiere are provided with additional protection. In a similar fashion, the sleeves 102a and 102b can be constructed of one or more plies of fabric having different relative lengths.

The plies 107a, 108a, 107b, and 108b are stitched together at the neck opening 105, the shoulder seams 106a and 106b, and around the armholes 103a and 103b. Optionally, first plies 107a and 108a can be stitched or surged along bottom edges 109 and 110 to form a hem or a finished edge. Also optionally, second plies 107b and 108b can be stitched or surged along a terminal edge 124 to form a hem or a finished edge, or can have an unfinished terminal edge 124 where the second plies 107b and 108b are constructed of a fabric that is not prone to fraying or unraveling. Alternatively, plies 107a and 107b can be stitched together along bottom edges 109 and 110 such that the plies 107a and 107b are joined to form a hem or a finished edge. In this embodiment, the sleeves 102a and 102b, as well as the collar 104 and the back portion 101b are constructed of a single ply of fire resistant fabric. The shirt 101 provides two or more plies of fire resistant fabric where the plies are needed fore safety in the left and right front panels 108 and 107, and one ply of fire resistant fabric elsewhere.

In one embodiment, the left and right front panels 108 and 107 of the shirt 101 comprise top plies 107a and 108a and bottom plies 107b and 108b of fire resistant fabric. The neck opening 105 is at the top of the front portion 101a and a stitched hem or surged edge is along the bottom edges 109 and 110 of the shirt 101. The stitching around the neck opening 105 and along the bottom edges 109 and 110 holds together the two or more plies 107a, 108a, 107b, and 108b of fire resistant fabric, which are otherwise continuously unbonded. The left front panel 108 and right front panel 107, are joined together by overlapping button hole panel 112 (not shown) and button panel 111. Stitching along the button hole panel 112 and button panel 111 holds together the two or more plies 107a, 108a, 107b, and 108b of fabric, which can be continuously unbonded. The back portion 101b and the sleeves 102a and 102b are constructed of a single ply of fire resistant fabric.

FIG. 8 illustrates another embodiment of the shirt 201 in accordance with the present invention. The shirt 201 is constructed of a fire resistant material, and comprises sleeves 202a and 202b, which extend from armholes 203a and 203b. A front portion 201a of the shirt 201 comprises left front panel 208 and right front panel 207, which are constructed from two-plies of fire resistant fabric of different lengths relative to each other. The left and right front panels 208 and 207 comprise first plies 207a and 208a of fire resistant fabric extending from shoulder seams 206a and 206b of the left and right front panels 208 and 207 of the shirt 201, and having a terminus at the bottom edges 209 and 210 of the front portion 201a of the shirt 201. Second plies 207b and 208b (shown in phantom behind the first plies 207a and 208a) of fire resistant fabric extend from the shoulder seams 206a and 206b of the left and right front panels 208 and 207 of the shirt 201 and have a terminus 226 (shown in phantom lines) located between the bottom of the arm holes 203a and 203b and the bottom edges 209 and 210 of the front portion 201a of the shirt 201. In this embodiment, and as an example of the variable length of the second plies 107b and 108b, the terminus 226 of the second plies 207b and 108b of fire resistant fabric is located approximately one-third of a distance measured from the bottom edges 209 and 210 of the front portion 201a of the shirt 201 to the bottom of the arm holes 203a and 203b of the left and right front panels 208 and 207 of the shirt 201.

FIG. 9 illustrates yet another embodiment of the shirt 301 in accordance with the present invention. The shirt 301 has sleeves 316a and 316b, which extend from armholes 317a and 317b. There is a collar 318 formed above the neck opening 319. Shoulder seams 320a and 320b extend from the armholes 317a and 317b to the neck opening 319. Front panel 322 is constructed from two or more plies of a fire resistant fabric of different lengths relative to each other. The front panel 322 comprises a first ply 322a of fire resistant fabric extending from shoulder seams 320a and 320b of the shirt 301 and having a length that terminates at the bottom edge 321. Second ply 322b (shown in phantom behind the first ply 322a) of fire resistant fabric extends from the shoulder seams 320a and 320b of the front panel 322 of the shirt 301 and has a terminus 326 (shown in phantom lines) located between the bottom of the arm holes 320a and 320b and the bottom edge 321. In this embodiment, and as another example of the variable length of the second ply 322b, the terminus 326 of the second ply 322b of fire resistant fabric is located approximately two-thirds of a distance measured from the bottom edge 321 of the shirt 301 to the bottom of the arm holes 320a and 320b.

It will be further apparent to those skilled in the art that various modifications and variations can be made to the shirt of the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention covers the modifications and variations of this invention provided that they come within the scope of the appended claims and their equivalents.

Claims

1. A fire resistant shirt having a front portion comprising two or more plies of fire resistant fabric and a back portion constructed of one ply of fire resistant fabric.

2. The shirt of claim 1, further comprising sleeves constructed of fire resistant fabric.

3. The shirt of claim 1, further comprising: a neck opening at the top of the front portion;a bottom edge along the bottom of the front portion, andstitching around the neck opening which holds together the two or more plies of fire resistant fabric.

4. The shirt of claim 1, wherein the front portion further comprises: a left front panel and a right front panel joined together by an overlapping button panel and button hole panel, andstitching along the button panel and button hole panel which holds together the two or more plies of fire resistant fabric.

5. The shirt of claim 1, wherein the bottom edge comprises a stitched hem.

6. The shirt of claim 1, wherein the two or more plies are continuously unbonded about a surface area of opposing faces of the plies.

7. The shirt of claim 2, wherein the sleeves comprise a single ply of fire resistant fabric.

8. The shirt of claim 3, wherein the two or more plies are continuously unbonded about a surface area of opposing faces of the plies.

9. The shirt of claim 4, wherein the two or more plies are continuously unbonded about a surface area of opposing faces of the plies.

10. A fire resistant shirt having a front portion comprising two or more plies of fire resistant fabric, wherein the front portion further comprises: a bottom edge;shoulder seams;two arm holes having a bottom;a first ply with a length extending from the shoulder seams to the bottom edge of the shirt, anda second ply with a length extending from the shoulder seams to a terminus between the bottom edge of the shirt and the bottom of the two arm holes.

11. The shirt of claim 10, further comprising: a back portion constructed of one ply of fire resistant fabric.

12. The shirt of claim 10, wherein the terminus of the second ply is located approximately at or between two-thirds and one-third of a distance measured from the bottom edge to the bottom of the two arm holes.

13. The shirt of claim 10, wherein the terminus of the second ply is located approximately at or between three-quarters and one-quarter of a distance measured from the bottom edge to the bottom of the two arm holes.

14. The shirt of claim 10, wherein the terminus of the second ply is located at approximately one-half of a distance measured from the bottom edge to the bottom of the two arm holes.

15. The shirt of claim 10, wherein the terminus of the second ply is located approximately at or between two-thirds and one-half of a distance measured from the bottom edge to the bottom of the two arm holes.

16. The shirt of claim 10, wherein the terminus of the second ply is located approximately at or between one-half and one-third of a distance measured from the bottom edge to the bottom of the two arm holes.

17. The shirt of claim 10, wherein the first ply and the second ply are continuously unbonded about a surface area of opposing faces of the first and second plies.

18. The shirt of claim 11, wherein the first ply and the second ply are continuously unbonded about a surface area of opposing faces of the first and second plies.

19. The shirt of claim 2, wherein the sleeves comprise a first ply and a second ply of fire resistant fabric, and wherein said first ply and second ply have different lengths relative to each other.

20. A torso-covering garment having a front portion comprising: at least two plies of fire resistant fabric, each fire resistant fabric ply having an arc thermal performance value (ATPV) equal to or greater than 4.2 calories per square centimeter;a neck opening at the top of the front portion;a hem along the bottom of the front portion;stitching around the neck opening and along the hem which holds together the two or more plies of fire resistant fabric, wherein the front portion further comprises a left front panel and a right front panel which are joined together by and overlapping button hole panel and button panel, andstitching along the button hole panel and button panel which holds together the two or more plies of fire resistant fabric.