1
Trenton A Niemeyer: Respiratory protective device. Filcon Corporation, James V Harman, February 11, 1992: US05086768 (47 worldwide citation)

The respiratory protective device minimizes dead space by locating the exhalation valve mechanism slightly spaced from, but directly in front of the mouth. The inhalation valve mechanism surrounds the streamlined flow path leading to the exhalation valve mechanism. The inhalation valve mechanism is ...


2
Trenton A Niemeyer: Alarm system for respirator apparatus and method of use. Filcon Corporation, Merchant Gould Smith Edell Welter & Schmidt, June 23, 1987: US04674492 (45 worldwide citation)

The alarm system of the present invention includes a pressurized air source for the purpose of pressurizing a face mask which surrounds the mouthpiece of respirator apparatus. An alarm indicating device is installed in the air line between the pressurized air source and the face mask. If the face ma ...


3
Trenton A Niemeyer: Mask and method of manufacture. Filcon Corporation, James V Harmon, August 28, 1990: US04951664 (32 worldwide citation)

A mask for filtering dust and other particulates from air to be breathed by a person and a process for making same. The mask includes a compressible strip covered partially by a sealing material around the entire contact path between the mask and the person's face. The compressible strip provides fo ...