Abstract: A method of making a filtering face mask, which method includes the steps of: (a) providing (i) a valve seat that comprises an orifice and a seal surface, wherein the orifice allows air to pass therethrough and is surrounded by the seal surface, and (ii) a single flexible flap; (b) supporting the single flexible flap non-centrally and operatively relative to the orifice of the valve seat to form an exhalation valve, the single flexible flap being supported such that there is an imposed curved profile that extends from a first point where a stationary portion of the flap is supported on the valve seat to a second point where a free portion of the flap contacts a seal surface; and (c) attaching the exhalation valve to a mask body that is adapted to fit over the nose and mouth of a person.

Abstract: A unidirectional valve, wherein the valve comprises a valve body including a frame, a valve opening through the frame, and a valve seat extending from the frame and at least partially surrounding the valve opening. The valve further includes a valve flap having a first portion attached to the frame and an adjacent second portion free to move from a first position where the second portion is in contact with at least a part of the valve seat to a second position where at least part of the second portion is spaced from the valve seat, wherein the valve flap has a nonuniform thickness. The thickness variations may occur between sides of the valve flap, and may also occur between the ends of the valve flap.

Abstract: A gaming table for supporting cards and gaming pieces such as dominos. The gaming table has game boards that include first and second major surfaces and first and second sets of slots. The first set of slots is sized and configured for supporting gaming pieces like dominos and is disposed within the first major surface of the game board. The second set of slots is sized and configured for supporting playing cards. The second set of slots is disposed on the first major surface of the game board but within the first set of slots to form a set of compound slots.

Abstract: An electret article that includes a polymeric material that has electric charge imparted thereto, that has a CF3:CF2 ratio of at least 0.15 and that has a fluorosaturation ratio greater than about 200. The electret article may be in the form of a porous web of polymeric fibers suitable for use as a filter. The inventive electret article is resistant to charge degradation upon exposure to high temperatures for prolonged time periods.

Abstract: An electret article that includes a polymeric material that has electric charge imparted thereto, that has one or more heteroatoms, that has a fluorosaturation ratio of less than 200, and that has an atomic percent fluorine of greater than about 40%. The inventive electret article is resistant to charge degradation upon exposure to high temperatures for prolonged time periods.

Abstract: A speech transmission adapter for use with a respirator mask. The respirator mask has an associated clean air source and defines a clean air envelope between the body of the respirator mask and the face of the wearer and is bounded by a sealing portion of the respirator mask, the clean air source, and an exhalation port. The speech transmission adapter comprises a peripheral housing, a speech reception device supported by the peripheral housing, a speech transmitter coupled to the speech reception device, and a port defined in the peripheral structure for enabling the passage of air therethrough. The peripheral housing is adapted to mate to the respirator mask in a manner that expands the clean air envelope defined therein to include the speech reception means within the clean air envelope without requiring structural modification to the respirator mask.

Abstract: A supplied air helmet 10 comprises a visor 14 and a face seal 12 that is secured to the visor. The face seal 12 includes a sealing member 18 and a frame member 16. The sealing member 18 extends radially inward from the frame member 16 and has first and second regions of permeability 20 and 22. The second region 22 has greater permeability than the first region 20. The use of a face seal 12 that has differentiated permeability allows for a controlled flow of air through the interior of the supplied air helmet 10.

Abstract: A filtering face mask 10 that has a mask body and a new exhalation valve 14. The mask body is adapted to fit at least over the nose and mouth of a person to help define an interior gas space when the mask is worn. The exhalation valve 14 permits fluid communication between the interior gas space and an exterior gas space. The exhalation valve 14 has a valve seat 20 and a flap 22. The valve seat 20 includes a resilient seal surface 24 and an orifice 30 through which exhaled air may pass to leave the interior gas space. The flap 22 is mounted to the valve seat 20 such that the flap 22 makes contact with the resilient seal surface 24 when the valve is in its closed position and such that the flap 22 can move away from the seal surface 24 in response to an exhalation to allow exhaled air to pass through the orifice 30 to ultimately enter the exterior gas space.

Abstract: A face mask for filtering contaminants from the air. The face mask includes a harness for securing the mask over the nose and mouth of the wearer and a nonwoven fibrous layer attached to the harness. The nonwoven fibrous layer contains at least 40 weight percent thermally bonding fibers, where at least 10 weight percent of the fibers in the nonwoven fibrous layer are bicomponent fibers. The nonwoven fibrous layer is molded in a cup-shaped configuration and has a surface fuzz value of not less than 7.5 after being subjected to a surface fuzz abrasion test.

Abstract: A respirator (10) that includes a face piece (14) and a cartridge receiving structure (22) located on the face piece (14). The face piece (14) is sized to fit snugly over the nose and mouth of a person, and the filter cartridge (12) is capable of being manually snapped into engagement with the cartridge receiving structure (22). The snap-fit can be instantaneously obtained without rotational movement of the filter cartridge (12), simply by pressing the filter cartridge (12) against the receiving structure (22).