Note: Descriptions are shown in the official language in which they were submitted.
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Firefighting Hood Treated
With a Water Repellant Finish
BACKGROLID
The present invention relates to hazardous duty garments and, more
particularly, to lightweight firefighter gannents which protect a wearer from
extreme ambient
conditions.
Protective garments are designed to shield a wearer from a variety of
environmental hazards, and firefighter garments are representative of such
garments. A
conventional firefighting ensemble comprises a turnout coat and pant, each of
which includes
an outer shell, a moisture barrier located within the outer shell, a thermal
liner located withir,
the moisture barrier and an innermost face cloth layer. The outer shell
typically is
constructed of an abrasion-, flame- and heat-resistant material such as a
woven aramid
material, typically NOMEX or KEVLAR (both are trademarks of E. I. DuPont de
Nemours &
Co., Inc.) or a polybenzamidazole such a PBI (a trademark of Celanese Corp.)
fiber material.
The moisture barrier typically includes a semipermeable membrane layer which
is moisture
vapor permeable but impermeable to liquid moisture, such as CROSSTECH (a
trademark of
W.L. Gore & Associates, Inc.). The membrane layer is bonded to a substrate of
flame- and
heat-resistant material, such as an aramid or PBI material.
The thermal liner is typically positioned within the moisture barrier in order
to
prevent the thermal liner from soaking up liquid moisture flowing through the
outer shell
from the ambient. The thermal liner typically comprises a relatively thick
layer of aramid
fiber batting or needlepunch, often quilted to a lightweight aramid face
cloth. The batting of
the thermal barrier traps air and possesses sufficient loft to provide the
necessary thernlal
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resistance, and the face cloth protects the batting of the thermal liner from
abrasion from the
wearer.
The aforementioned components typically are arranged within the garment so
that the moisture barrier layer is positioned between the therrnal liner and
the outer shell.
This is necessary to prevent the batting material of the thermal liner from
absorbing an
excessive amount of liquid moisture from the ambier.t, which increases the
overall weight of
the garment and reduces breathability of the thennal liner, thereby increasing
the stress
imposed by the garment on the wearer, and reduces its loft and thermal
resistance
characteristics. However, one disadvantage with such an arrangement is that
the laminated
membrane of the moisture barrier is relatively delicate and can be damaged by
heat, abrasion
or puncture. Such damage results in increased exposure of the thermal liner to
liquid
moisture, which increases liquid moisture absorption.
Another disadvantage inherent in such an arrangement is that the moisture
barrier layer adds to the bulk and weight of the garment and inhibits freedom
of movement of
the wearer, producing a "hobbling effect," increasing the stress imposed on
the wearer in
situations requiring high activity, and accelerates the onset of fatigue.
Furthermore, with such
an ensemble some perspiration moisture vapor from the wearer is absorbed by
the thermal
liner. Moreover, the combination of a discrete moisture barrier and thermal
liner limits
breathability, especially if the thermal liner is positioned witliin the
moisture barrier.
Accordingly, there is a need for a protective garment in which the
susceptibility of the therrnal liner to absorption of perspiration moisture
vapor and other
moisture vapor is minimized; a protective garrnent which is relatively thin
and lightweight,
yet provides adequate thermal protectior.; a protective garment which is
inherently able to
withstand a temperature of 500 F. for at least five minutes without igniting,
melting or
dripping, making it suitable for use as a f refighting garment; and a
protective garment which
minimizes the restriction of movement and tiobbling effect characteristic of
conventional
firefighting garments.
.
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SuMMARY
The present invention is a protective garment which is relatively lightweight,
yet possesses relatively high resistance to liquid water absorption with
relatively high
moisture vapor transport characteristics when compared to conventional
firefighter garments.
The garment of the present invention comprises an outer shell, a thermal liner
positioned
within the outer shell, and a face cloth layer positioned within the thermal
liner -- a discrete
moisture barrier layer is not present or required. At least the outer shell
and the face cloth
layer are treated with a durable, water repellant finish to reduce penetration
of moisture
through either of these layers to the thermal liner. Preferably, the thermal
liner is also treated
with a durable, water repellant finish to minimize liquid moisture absorption.
Such durable,
water repellant finishes are provided by treating the components with a
commercially
available perfluorohydrocarbon finish such as TEFLON (a trademark of E. I.
DuPont de
Nemours & Co., Inc.). and/or SCOTCHGU.ARD (a trademark of Minnesota Mining &
Manufacturing Co.).
In a first embodiment of the present invention, a firefighting garment
consists
essentially of an outer shell of abrasion-, flame- and lieat-resistant
material selected from a
group consisting of an aramid material, a blend of aramid materials, PBI
material and a blend
of aramid and PBI materials; a thermal liner positioned within the outer
sliell and including a
batting, needlepunch or nonwoven aramid material, or a blend of such aramid
materials,
stitched to a first face cloth layer of aramid material; and a second face
cloth layer of aramid
material, positioned within the thermal liner; where the material of the outer
shell, the thermal
liner, and the second face cloth layer are all treated with a durable, water
repellant finish.
Such a firefighting garment does not require a discrete moisture barrier
layer,
yet possesses the necessary thermal protection ratings for use as a
firefighting garment. Thus,
the firefighting garment is relatively thin and lightweight, thereby
minimizing the bulk and
reducing the hobbling effect of such a garment. Furthermore, the elimination
of a discrete
moisture banier reduces the material costs of the garment. The design of the
thermal liner
substantially reduces the amount of liquid moisture it absorbs, thereby
maintaining the
insulative properties of the thermal liner and maintaining desirable
lightweight properties for
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longer periods. Another advantage of such a design is that the transport of
moisture vapor
.
through the garment is enhanced.
In an alternate embodiment of the present invention, a discrete moisture
barrier
layer is provided, but is positioned between the treated thermal barrier and
the inner face
cloth. By providing such a moisture barrier, the penetration o.f blood-borne
pathogens from
the environment to the wearer is minimized. Furthermore, the positioning of
the treated
thermal liner between the outer shell and the moisture barrier protects the
moisture barrier
from damage froni excessive thermal heat and from abrasion caused by the outer
shell.
In a second alternate embodiment, a firefighter garment includes an outer
shell, a moisture barrier positioned inside and adjacent to the outer shell, a
therrnal liner
positioned inside of the moisture barrier and an inner face cloth. The thermal
liner is treated
to have a moisture repellant finish as with the other embodiments. The thermal
liner of this
embodiment thus will absorb only a minimal amount of perspiration moisture
from the
wearer, from a breach in the moisture barrier or from openings in the neck and
sleeve, and
generally will be shielded from ambient moisture by the conventional moisture
barrier.
The thermal liner typically includes knitted wristlets and a knitted collar
attached thereto. Therefore, in one aspect of the present invention, the
wristlets and collar of
the garment, whether attached to the thermal liner or not, are also treated
with a durable,
water repellant finish to minimize liquid moisture absorption or penetration.
This is
important especially in cold environments where wristlets which have absorbed
water during
use may freeze. Wristlets of the present invention will not absorb water
appreciably and are
less likely to freeze. Finally, it is yet another aspect of the present
invention to provide a
protective firefighting hood that has been treated with a durable, water
repellant finish to
minimize liquid moisture absorption therethrough.
Accordingly, it is an object of the present invention to provide a protective
garment in which the thernial liner absorbs a minitnal amount of liquid
moisture; a protective
garment which reduces the amount of moisture absorbed by the thenmal liner; a
protective
garment which does not require a discrete moistin-e barrier layer, yet
possesses the necessary
thermal protection ratings for use as a firefighting garment; a protective
garment which is
relatively thin and lightweight, thereby minimizing the bulk and reducing the
hobbling effect
of such a garrnent and the reducing the material costs of the garment; and a
protective
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garment that enhances the transport of moisture vapor therethrough for
breathability and
greater cooling.
Other objects and advantages of the present invention will be apparent from
the following description, the accompanying drawings and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. I is a somewhat schematic, perspective view of a firefighter garment
incorporating a preferred embodiment of the present invention;
Fig. 2 is an exploded, perspective view of a section of a detail of the
garment
of Fig. 1;
Fig. 3 is an exploded, perspective view of a detail of an alternate embodiment
of the present invention;
Fig. 4 is an exploded, perspective view of a detail of a second alternate
embodiment of the invention;
Fig. 5 is an exploded, perspective view of an embodiment of the garment of
Fig. 1, where the thennal liner and inner face-cloth layer comprise an inner
liner that is
removable from the outer shell; and
Fig. 6 is a perspective view of a firefighting hood incorporating an
embodiment of the present invention.
DETAILED DESCRIPTION
As shown in Fig. 1, the present invention is a protective garment in the form
of
a firefighter gannent, generally designated 10. It is to be understood that
the present
invention is not limited to firefighter garments, but can be incorporated in
work garments and
other hazardous duty garments, such as brushfire and EMS gannents, in both
coat and pant
combinations and "jumpsuit" styles, without departing from the scope of the
invention. The
garment 10 is a firefighter turnout coat having a body portion 12, sleeves 14,
16, a neck
opening 18, a collar 20 surrounding the neck opening, and a front closure,
generally
designated 22. Front closure 22 is of conventional design and includes a storm
flap 23. The
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closure 22 is secured by snaps, or altematively, strips of hook and loop
fastener material (not
shown) in combinatio-i with mechanical locking means such as hook and "D"
combinations
24 extending between the flap 23 and body portion 12, or a slide fastener (not
shown).
As shown in Figs. 1 and 2 the garment 10 includes an abrasion, heat and flame
resistant outer shell, generally designated 26, which covers substantially the
entire outer
surface garment. The outer shell is compact weave of an aramid material such
as NOMEX or
KEVLAR, a blend of such aramid materials, a PBI material, or a blend of aramid
and PBI
materials. The thermal liner, generally designated 28, extends substantially
throughout the
garment 10 and includes layer 30 of insulative material quilted to a layer 32
of aramid face
cloth material. The insulation material can be a batting, needlepunch, or
multi-layer
nonwoven aramid material. A second layer 34 of aramid face cloth material is
positioned
within the thermal liner 28 and protects the thermal liner from abrasion from
the clothing of
the wearer. Additionally, it is within the scope of the invention that the
foregoing materials
may be readily substituted with other materials having similar protective
properties, or
altemative protective properties corresponding to other specialized hazardous
use garments.
As shown in Fig. 5, the thermal liner 28 and face cloth layer 34, in one
einbodiment, may be
attached to each other to form an inner liner 35 that is removable from the
outer shell 26.
The outer shel126, thermal liner 28 and face cloth layer 34 each are treated
with a durable, water-repellant finish prior to assembling these components to
form the
garment 10. A preferred finish is a perfluorohydrocarbon finish such as TEFLON
Fabric
Protector. Preferably, a loading of at least 2.5% on weight of fabric of
TEFLON is used. A
commercially available method for finishing the above components with TEFLON
Fabric
Protector is provided by E. I. DuPont de Nemours & Co., Inc. of Wilmingtan,
Delaware,
13898.
It is within the scope of the invention that other suitable water repellant
finishes, coatings or treat.~r~ents mav also be used, such as treating the
components with a
perfluororiydrocarbon finish such as SCOTCHGUARD, or by applying a silicon,
resin, wax
or plastic finish. In the preferred embodiment of the invention, each
component of the
garment 10 possesses certain characteristics which makes it particularly
suitable for use in a
hazardous duty garment, particularly a firefighter garment. The ensemble of
the outer shell
26, thermal liner 28 and face cloth layer 34, each treated with a durable,
water-repeliant finish
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according to the invention, meets certainrequirements of the N.F.P.A.
(National Fire
Protection Association) 1971 Standard. Specifically, the ensemble resists
igniting, melting or
dripping when exposed to 500 F for at least five minutes. Furthenmore, the
water-repellant
finishes applied to the components of the ensemble are durable in that they
withstand at least
25 launderings without appreciable diminution in water repellancy.
However, a durability of withstanding at least 5 launderings without
appreciable diminution in water repellancy is within the scope of the
invention.
Consequently, the firefighting garnient 10 does not require a discrete
moisture
bamer because the water-repellant finish of the outer shell 26 and face cloth
layer 34
substantially prevent liquid moisture from reaching and being absorbed by the
thernnal liner
28. Furthermore, because the thermal liner 28 is also preferably treated with
a water-repellant
finish, it will be much less susceptible to absorbing and retaining liquid
moisture that
penetrates through the outer shell 26, face cioth layer 34, or enters through
a seam or opening.
Additionally, by eliminating a discrete moisture barrier component, the
breathability of the
garment is increased, and the weight and "hobbling" effect of the garment is
substantially
decreased.
Referring to Figs. 1 and 5, the thermal liner 28 includes a pair of knitted
wristlets 42 and a knitted collar 44 stitched or otherwise attached thereto.
The wristlets 42
and collar 44 are preferably knitted from an aramid material such as NOMEX or
KEVLAR, a
blend of such aramid materials, a PBI material, or a blend of aramid and PBI
materials.
Preferably, the wristlets 42 and/or collar 44 are also treated with a durable,
water-repellant
finish as described above so as to substantially prevent the absorption or
penetration of liquid
moisture theretlirough. Of course, it is within the scope of the invention
that the treated
wristlets 42 and collar 44 be separate from the thermal liner 28 and/or
attached to another
componcnt of the garment, such as the outer shell 26.
It is also within the scope of the present invention to use a therm3l liner
that
includes a layer of aperttired, closed-cell foam as described in U.S. Patent
5,697,101 filed February 5, 1996 or U.S. Patent 5,924,134 filed May 15, 1997.
Such thermal liners do not absorb significant amounts of liquid moisture and
can be
made thinner than conventional thermal liners, yet still meet the overall
thermal
requirements for firefighting garments.
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The method of constructing the garment of the present invention is as follows.
A relatively lighhveight, low volume protective garment is constructed by
treating an outer
shell of abrasion, flame and heat resistant material with a durable, water-
repellant finish;
treating a thermal liner with a durable, water-repellant finish; treating a
face cloth layer of
material with a durable, water-repellant finish; and assembling the garment by
positioning the
thermal liner within the outer shell and the face clotli layer within the
thermal liner. The
means for cutting and attaching the various layers together to form the
garment will be
apparent to those skilled in the art.
As shown in Fig. 3, an alternate enibodiment 10' of a firefighter garment of
the
present iiivention includes a thermal liner 28 adjacent to the outer shel126
as with the
embodiment of Figs. 1 and 2; but includes a discrete moisture bantier layer 36
between the
thermal liner 28 and the face cloth layer 34. The moisture barrier 36 includes
a
semipermeable membrane layer 38, which is moisture vapor permeable but
impermeable to
liquid nioisture, such as CROSSTECH, bonded to a substrate 40 of flame- and
heat-resistant
material, such as an aramid or PBI material. By providing such a moisture
barrier 36, the
penetration of blood-bozne pathogens from the environment to the wearer is
minimized.
Furthermore, the positioning of the thermal liner 28 between the outer
shel1.26 and the
moisture barrier 36 protects the moisture barrier from damage from excessive
thermal heat
and from abrasion caused by the outer shell. With the embodiment of Fig. 3,
the addition of a
discrete nioisture barrier 36 (as opposed to the water-repellerit thermai
liner 28 acting also as
a moisture barrier for the ensemble) to the ensemble of the outer shell 26,
thermal liner and
face cloth layer 34, the entire ensemble 10' meets tl-ie N.F.P.A. 1971
Standard. Not only does
the garment 10' resist burning, melting or dripping when exposed to 500 F for
at least five
minutes, as does the garment 10 of Figs. I and 2, but the garment passes the
liquid
penetration test (ASTM test F1359), as well as all other tests comprising the
Standard. The
treatments applied to the components of the garment 10' of Fig. 3 are also
sufficiently durable
to witlistand at least 5 launderings, and preferably at least 25 launderings.
As shown in Fig. 4, in another alternate embodiment 10" of the garment of the
present invention, the moisture barrier 36 is positioned adjacent to the outer
shel126, and the
thermal liner 28 is positioned in between the moisture barrier and the face
clotli layer 34.
With this embodiment, the moisture barrier 36 protects the durable, moisture-
resistant
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thermal liner 28 from liquid moisture penetrating the outer shell 26. The
advantage of
utilizing the moisture resistant therinal liner 28 of the present invention in
this embodiment is
that the moisture resistance of the thermal liner minimizes its absorption of
liquid perspiration
from a wearer, as well as absorption of liquid moisture from wicking from
sleeve and neck
openings or from a small tear in the moisture barrier.
Furthermore, the garment 10" of Fig. 4 meets the N.F.P.A. 1971 Standard. In
particular, the garment 10" resists igniting, melting or dripping when exposed
to 500 F for at
least five minutes, passes the liquid penetration test, and passes all other
tests comprising the
Standard. While in the preferred form of the embodiment of the garment 10" the
outer shell
26, thermal liner 28 and face cloth layer 24 are each treated to have the
durable, water-
repellent finish described with respect to the garment 10, the gannent 10" can
be modified
such that the face cloth layer 34 is not treated with the durable finish.
As shown in Fig. 6, the present invention also provides a firefighting hood 48
treated with a durable, water-repellant finish as described above. The hood 48
is preferably
construcLed from two layers of knitted or woven flame and heat resistant
aramid material
(such as NOMEX or KEVLAR, a blend of such aramid materials, a PBI material, or
a blend
of aramid and PBI materials) to protect the firefighter against bums in the
regions covered by
the hood. The hood 48 includes a head portion 50 shaped to cover the forehead,
ears and chin
of the wearer and an optional bib portion 52 shaped to cover the neck and an
area of the
wearer's chest and shoulders. The head portion 50 includes a substantially
oval front opening
54 for exposure of the wearer's eyes, nose and mouth. While all layers of the
hood 48 are
preferably treated with the durable, water-repellant finish, it is within the
scope of the
invention that only one, or less than all, of the layers be treated with the
durable, water-
repellant finish. Because the treatment substantially prevents the absorption
or penetration of
liquid moisture through the hood 48, the treatment also substantially prevents
the penetration
of blood-borne pathogens through the hood.
While the forms of apparatus herein described constitute preferred
embodiments of this invention, it is to be understood that the invention is
not limited to these
precise forms of apparatus, and that changes may be made therein without
departing from the
scope of the invention.
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