Abstract: A fire and explosion detection and suppression system protects a hangar within which may be stored jet aircraft whose engines may be run up particularly in the re-heat mode. Two radiation sensors are mounted within the hangar and detect for at least predetermined amounts of radiation of predetermined and different types (e.g. one sensor may be a UV sensor and the other may be an IR sensor). When they simultaneously detect sufficient radiation, they operate an AND gate. This fires off suppressor units. To prevent false alarms due to radiation emitted by a running jet engine or a jet engine running in re-heat mode, such a running jet engine is sensed by a transducer responsive to the emitted acoustic or vibrational energy. This blocks the AND gate.

Abstract: A fire and explosion detection and suppression system protects two physically adjacent zones in each of which there is a UV sensor and an IR sensor. In each zone, simultaneous detection, by the pair of sensors, of sufficient respective levels of UV and IR causes an AND gate to set off suppressor units to discharge suppressant into the zone being protected. Some of this suppressant may drift into the adjacent zone and may attenuate UV radiation in that zone. Thus, for at least a temporary period, that zone may be incapable of detecting a subsequently occurring fire or explosion. Therefore, by means of a latching circuit the output signal of an operating one of the AND gates temporarily renders the circuit of the adjacent zone capable of operating independently of UV radiation.

Abstract: A fire detection system comprises a plurality of individual fire detection-suppression units which all have their own individual standby electrical power supply. Each has a radiation detector for fire detection and its own source of fire suppressant. In the event of any of the units detecting a large fire, it automatically releases suppressant from its own source. In addition, all the units are connected to a master control station via a data bus. Any individual unit sensing a large fire signals this fact to the master control station which then enables the immediately adjacent individual units so as to permit those units, only, to release their fire suppressant if and only if they detect at least a "small" fire (and also provided that the master control station determines that not less than a predetermined number of the units still have functional fire suppressant sources).

Abstract: A portable, self-contained dental operatory is disclosed. The operatory includes all of the equipment necessary for the ordinary practice of dentistry contained in a cabinet that serves both as a compact carrying case and as a chairside dental workbench. The cabinet includes foldable front and top panels that fold outwardly and downwardly to form a dental workbench positioned in front of a tool support panel that supports dental handpieces and other equipment. The cabinet further contains an electric air compressor that supplies pressurized air to drive the handpieces and to provide a source of pressurized water from a water reservoir. The operatory further includes a vacuum bottle that may be selectively evacuated by the air compressor as required to operate an oral saliva evacuator. The air compressor includes an electric motor that can be tapped to drive grinding and polishing equipment.