This invention relates to the field of protective apparel, specifically hoods and escape mask systems designed to protect wearers from exposure to chemical and/or biological hazards, and more specifically to neck dams used to create a protective seal between such hoods and masks and the neck of the wearer.
Workers in certain hazardous professions, such as emergency rescue workers and military personnel, may in certain circumstances deal with various chemical or biological agents, the inhalation of which, or exposure to which, can be irritating, health-threatening, or even life-threatening. Members of those professions have benefited from the development of hoods and escape mask systems designed to protect the wearer by providing a physical barrier between the wearer and the external environment, and thus preventing chemical or biological threats from contacting the wearer. Such hoods and masks are generally fluid- and air-tight, at least partially envelope the wearer's head, and interface with the wearer's neck. The effectiveness of such hoods and masks in providing complete protection to the wearer depends in part on the ability of one portion of the hood or mask, the neck dam, to form an adequately sound seal about the wearer's neck.
A neck dam is a structure surrounding an opening in a protective hood or mask through which a wearer inserts his or her head into the hood or mask. The neck dam, typically constructed of an elastic or resilient material, is generally smaller in diameter than the head of the wearer, and can be stretched so that the wearer can insert his or her head into the hood. When released, the neck dam contracts and thus becomes positioned proximate to and generally against the wearer's neck, often forming a seal that prevents the entry of gases or agents from the external environment into the hood.
Traditionally, a neck dam relies on the elasticity of the material from which it is constructed to create the seal about the wearer's neck. This construction has certain limitations and drawbacks. For example, the elastic material chosen for use in traditional neck dams may not conform to the physical dimensions of a wearer's neck. In the case of a wearer with a larger diameter neck, the dam may be too tight, possibly leading to shortness of breath and reduced blood flow to the brain due to the pressure of the neck dam on the individual's windpipe and carotid arteries. In the case of a wearer with a smaller diameter neck, the neck dam may be too loose, and thus compromise the quality of the desired seal. When there is not enough sealing pressure to provide an adequate seal around the wearer's neck, movements of the head, such as looking upward or downward, can cause the neck dam to leak, permitting chemical or biological agents to enter the hood or mask.
Accordingly, there is a need for a device and method that may improve the level of protection and/or the level of comfort afforded by neck dams of chemical and biological hoods and escape mask systems.
According to one aspect of the invention, a collar for a neck dam includes a substantially vapor-proof material with at least a portion adapted to engage a wearer's neck without substantial constriction. The material of the collar is sufficiently compressible to cushion the neck of the wearer against an opposing portion of the neck dam if and when such neck dam pushes or biases against the wearer's neck. The material for the collar may have a sufficient thickness to fill in any gap or gaps that may form between the neck and the neck dam while the user is wearing the neck dam.
According to another aspect of the invention, the material has been configured so as to form a cylindrical passage with two, opposite open ends. In this aspect, the material extends between the open ends, which are sized to be stretched over the wearer's head so as to put the cylindrical passage around the wearer's neck.
According to a still further aspect of the invention, the material comprises a flexible planar fabric having opposite, substantially planar surfaces to define a cylindrical wall. In this aspect of the invention, the thickness of the cylindrical wall corresponds to the thickness of the material. The collar may be constructed with material that is sufficiently flexible to be folded over on itself, which increases the overall thickness of the material extending from the neck to the neck dam. Substantially vapor proof materials include, rubber, synthetic rubber, neoprene, other rubber-like materials, and the like. Silicone rubber may be also be used in certain applications, although it is not considered entirely vapor proof.
According to yet another aspect of the invention, the neck dam collar is used with or is part of an article of apparel.
The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Additional features of the invention will be apparent from the description and drawings and from the claims.
Like reference symbols in the various drawings indicate like elements.
Referring now to
Neck dam collar 11 is preferably formed into a cylindrical passage 13 having two, opposite open ends 15, 17 and a substantially planar cylindrical wall 19 extending between ends 15, 17. Cylindrical passage 13 may have an inside diameter of about 3.5 inches to about 3.625 inches, however, cylindrical passage 13 may have other inside diameters. Planar cylindrical wall 19 is sufficiently expandable or elastic in the circumferential direction AA (
The material of collar 11 is likewise resiliently compressible, at least in the orthogonal or radial direction B (
It will be appreciated from the description above that when neck dam collar 11 is worn, it engages the wearer's neck 13 snugly, but comfortably. “Engaging” the wearer's neck means it is disposed against the neck.
More particularly, in the case of a wearer with a larger diameter neck, a conventional neck dam may be too tight, possibly leading to shortness of breath and reduced blood flow to the brain due to the pressure of the neck dam being exerted over a relatively small area against the individual's windpipe and carotid arteries. In the case of a wearer with the larger diameter neck, the cushioning characteristics of collar 11 may reduce the discomfort by dispensing or dissipating the orthogonal forces of neck dam 23, as shown by arrows C in
It may be desirable in some applications to employ collar 11 in a folded configuration, such as shown in
The collar 11 in this embodiment has been secured to a protective suit 125. Collar 11 likewise could be secured to neck dam 23 itself.
Although neck dam collar 11 has been shown in this embodiment as a flexible, planar wall 19, other configurations are possible so long as a portion of collar 11 is disposed snugly but comfortably between the wearer's neck and one or more opposing portions of neck dam 23. Such alternate configurations, like that illustrated in
Neck dam collar 11 can have a variety of suitable lengths 24 for cylindrical wall 19. Generally, the height 24 is sufficiently long to account for variations in the vertical position of opposing neck dam portions 20 relative to the wearer's neck. The height 24 may be about 4.5 inches; however, alternative heights are contemplated. In other words, numerous geometric variables will dictate the range of vertical positions of opposing neck dam portions 20 and it is preferable, but not required, for collar 11 to remain between the opposing portions 20 and the wearer's neck regardless of such variations in the fit or neck dam geometry.
The material of neck dam collar 11 may be a single-ply rubber material such as silicone rubber, or the like, and it will be appreciated that laminate structures, such as neoprene, are likewise suitable. The functional characteristics of the two layers can be varied relative to each other to enhance the effectiveness of the collar. Thus, for example, the outer layer (not shown) may be selected to have more resilience to better dissipate the forward force of opposing portion 20, whereas the inner layer (not shown) may have more give or cushioning to enhance comfort. The reverse construction may likewise be suitable.
The invention described herein may be manufactured, used and licensed by or for the United States Government.
Number | Name | Date | Kind |
---|---|---|---|
3958275 | Morgan et al. | May 1976 | A |
4015295 | Lancaster et al. | Apr 1977 | A |
4365351 | Doerschuk et al. | Dec 1982 | A |
6854134 | Cleveland | Feb 2005 | B2 |
6854459 | Cox | Feb 2005 | B1 |