Abstract: An automatic system for calibrating gas sensors comprising a source of SPAN gas and a source of ZERO gas, and a means to control the flow of these gases to sensors. The system schedules and makes all required sensor value corrections and adjustments without human intervention. High resolution monitoring enables life extensions for the sensors, as well as higher accuracy monitoring than would be reasonably expected from low cost sensors.

Abstract: A field monitoring and communication system for arranging circuits and components for environmental and other types of monitoring systems includes: (a) microprocessor-based modules for communications and a variety of input/output types and combinations: (b) remote and optionally, proximal calibration and regulator modules: (c) a variety of sensor inputs optionally comprising intrinsically safe barriers.

Abstract: An automatic system for calibrating gas sensors comprising a source of span gas and a source of zero gas, a means to control the flow of these gases to sensors. The system makes all required sensor value corrections and adjustments without human intervention.

Abstract: A field monitoring and communication system for arranging circuits and components for gas monitoring systems includes: (a) microprocessor-based modules for communications and input/output; (b) remote calibration and regulator modules; (c) sensor inputs optionally comprising intrinsically safe barriers.

Abstract: An obscuration type optical smoke monitor is provided for use particularly in dusty and dirty environments. The smoke monitor comprises a housing enclosing a smoke monitoring chamber; two access ports located opposite each other on the housing; a shunt air flow path located between said two access ports; means to conduct air from said access ports through an optical chamber; a light emitting diode at the first end of said optical chamber, which light emitting diode produces a light beam axially through the center of said optical chamber; a photo transistor at the second end of said optical chamber to receive the light bean and issue an electrical signal proportional to the received light intensity; and an electronic module which provides variable electronic output, generating an analog output essentially proportional of the optical obscuration caused by the smoke.

Abstract: The invention relates broadly to a fluorescent lamp construction adapted for use with hats or caps worn by workers in various occupations. The so-called hard hats are now largely worn by workers in hazardous locations, such as mining, construction, service and the like, and our improved fluorescent lamp construction is especially suited for attachment to a hard hat and the invention includes new and novel connection means.The fluorescent lamp is contained within an oblong housing that is removably held horizontally at the front of the hard hat and the lamp is energized by a battery which is carried on the person of the worker, such as by means of a carrying case having a clip for connecting it to a belt worn by the worker.To achieve a high level of light output at low temperatures, the invention includes means for conserving heat generated by the fluorescent lamp. Also, to reduce glare, the invention includes a new and novel means for dispersing the light from the lamp.

Abstract: The invention relates broadly to a fluorescent lamp construction adapted for use with hats or caps worn by workers in various occupations. The so-called hard hats are now largely worn by workers in hazardous locations, such as mining, construction, service and the like, and our improved fluorescent lamp construction is especially suited for attachment to a hard hat and the invention includes new and novel connection means.The fluorescent lamp is contained within an oblong housing that is removably held horizontally at the front of the hard hat and the lamp is energized by a battery which is carried on the person of the worker, such as by means of a carrying case having a clip for connecting it to a belt worn by the worker.To achieve a high level of light output at low temperatures, the invention includes means for conserving heat generated by the fluorescent lamp. Also, to reduce glare, the invention includes a new and novel means for dispersing the light from the lamp.