Abstract: An air filtration system and a helmet for use in the air filtration system are disclosed and utilized to filter air between a head and body of a user and an external environment. The air filtration system and helmet include inner and outer shells that define an air flow channel for channeling air about the user. A fan module is mounted between the inner and outer shells and a scroll housing is mounted adjacent the fan module. The scroll housing includes an air inlet for drawing air into the air filtration system and helmet, and at least one air outlet to distribute air flow to the air flow channel. The helmet includes air exits at front and rear sections that are in fluid communication with the air flow channel and the air outlet or outlets. The air filtration system includes a gown operating as a filter for filtering the air.

Abstract: An air filtration system and a helmet for use in the air filtration system are disclosed and utilized to filter air between a head and body of a user and an external environment. The air filtration system and helmet include inner and outer shells that define an air flow channel for channeling air about the user. A fan module is mounted between the inner and outer shells and a scroll housing is mounted adjacent the fan module. The scroll housing includes an air inlet for drawing air into the air filtration system and helmet, and at least one air outlet to distribute air flow to the air flow channel. The helmet includes air exits at front and rear sections that are in fluid communication with the air flow channel and the air outlet or outlets. The air filtration system includes a gown operating as a filter for filtering the air.

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 speech transmission adapter and a respirator mask comprising a speech transmission adapter. The respirator mask comprises an inhalation port, an exhalation port, and a speech transmission adapter in detachably sealed engagement with the inhalation port. The adapter comprises a peripheral housing, a speech reception means supported by the peripheral housing, and a speech transmission means operably coupled to the speech reception means. The speech reception means receives sound pressure generated by a wearer of the respirator mask, and the speech transmission means conveys signals representative of such sound pressure to an external speech transducer. The adapter mates to the inhalation port of a respirator mask and expands the clean air envelope defined within the mask to include the speech reception means within the clean air envelope without requiring structural modification of the respirator mask.

Abstract: An improved oral/nasal mask-hood is provided for protection of individuals in the event of fire or smoke exposure. When attached to a supplemental supply of oxygen the mask-hood also provides hypoxia protection to individuals exposed to decompression as in some aircraft incidents. The mask-hood employs a five stage filtering process for converting toxic atmospheric air to breathable fresh air. The hood covers the wearer's head, neck and shoulder area. A neck seal is provided inside the hood for preventing gases from locating within the hood and irritating the wearer's eyes. A transparent member is located on the hood adjacent the wearer's line of sight to provide visibility during the emergency. The hood-mask device, as assembled, is small enough to retrofit into the space provided for the present decompression mask alone.

Abstract: A scuba diving regulator includes a casing, a mouth piece, an air valve unit, an audio unit, a nozzle unit, an air charge unit and an air discharge unit. The casing has an alarm connector, a whistle connector linearly aligned with the alarm connector and a mouth piece connector for engaging with the mouth piece. The casing includes therein a longitudinal chamber adjacent a body. The air valve unit engages with the alarm connector and includes an alarm valve, an elastic member and a push button engaged with the elastic member for open or close the alarm valve. The audio unit engages with the whistle connector and includes a cylinder, an impact member located in the cylinder and a piston reciprocally movable in the cylinder for hitting the impact member to produce audio alarm sound. The nozzle unit is held in the casing and is screwed and sealed in the chamber by means of the screw member and a seal ring, and includes an air flow member which engages with the alarm valve.

Abstract: The invention is directed to a voice transmitter for a breathing protective mask. The voice transmitter includes a membrane housing (2) and a clamping ring (3) which can be connected to the membrane housing (2). The voice transmitter also includes a voice membrane (4) between the membrane housing (2) and the clamping ring (3). The voice membrane (4) has an outer membrane portion (14) which is accommodated at a connecting location between the clamping ring (3) and the membrane housing (2). An inner portion (15) of the membrane (4) is tensioned over an annularly-shaped projection (8) located on the membrane housing (2). The pretensioning of the voice membrane is adjusted in a simple manner in that the clamping ring (3) has an annularly-shaped support surface 13 for the inner membrane portion (15) and that the connecting location is configured as a threaded connection (7, 10).

Abstract: Mouthpiece and speaker assemblies for underwater speech using SCUBA and snorkel equipment, which mouthpiece is characterized by a molded rubber or plastic mouthpiece having a regulator or snorkel connector, a lip cup and a pair of elongated, serpentine or curved teeth grips or bites extending from the lip cup for gripping by the jaw teeth of a SCUBA diver or snorkeler and facilitating movement of the lips to enable underwater speech. The mouthpiece is designed for attachment directly to an underwater speaker, a snorkel, a snorkel and speaker combination, or to the mouthpiece of a conventional second-stage regulator and speaker combination. The underwater speaker includes a pair of flexible membranes connected at a common perimeter and designed to pulse and flex responsive to the pressure pulses of a diver or snorkeler's breath and voice.

Abstract: In order to equalize the pressure between the interior of an unit accommodating chamber and the outside of a mike casing without reducing a waterproof performance and an acoustic characteristic, there is provided a waterproof type microphone, which includes a mike casing 11 provided with an unit accommodating chamber having a sound receiving opening portion 141; a mike unit accommodated in the unit accommodating chamber 14; and a waterproof membrane 19 airtightly mounted on the sound receiving opening portion 141; the waterproof microphone further including an venting hole 21 formed in the mike casing 11 to cause the unit accommodating chamber to be communicated with outside of the mike casing 11 and a pressure equalizing membrane 22 mounted on the venting hole 21.