Abstract: An air flow and filtration control system in the form of a headgear which is worn by a physician during a surgical procedure, a technician during an assembly process, or any other user wherein controlled air flow and air filtration is required or desired. The system includes a lightweight headgear structure which substantially surrounds the upper portion of the head of the wearer. A fan is mounted in the headgear structure and is positioned to move air relative to the headgear structure. A shroud (or hood) can be draped over and attached to the headgear structure in such a fashion as to completely cover the headgear structure and to cover at least a portion of the wearer in order to maintain sterile or controlled environmental conditions relative to the wearer. Typically, the shroud may include at least one filtration area (which may comprise the entire shroud) and a screen at the front of the apparatus for viewing therethrough.

Abstract: An Improvement to enhance the usability of magnetic compasses by eliminating acceleration and turning errors, especially in aviation applications, without compromising simplicity and reliability. The improvement includes the addition of a weightless mass to the bar magnet of a conventional magnetic compass to counteract undesirable inertial forces on the bar magnet.

Abstract: This invention is directed to a unique type of form to be used with an optical mark sensing device known as a mark read scanner for reading marks on the form. Form characteristics are defined by “graphic switches” printed near the lead edge of the form. Each “graphic switch” has four distinct settings. The expense of completely replacing the internal program of a scanner when a user requests a variation of a test form that had not been pre-programmed into the original specification of the scanner is eliminated.