Electronic plant moisture sensor; Electronic proximity sensors and switches; Environmental monitoring system comprised of meters and sensors that measure pressure, humidity, temperature and includes alarm and reporting functions; Gas sensors for measuring gas concentration; Humidity sensor with integrated digital and analog output circuitry used in automotive, appliance and light industrial applications to sense both relative humidity and temperature environmental conditions; Light systems comprising light sensors and switches; Liquid level sensors; Photoelectric sensors; Pressure sensors; Pressure switches and sensors for monitoring, controlling, and switching hydraulic or pneumatic systems; Safety sensors, namely, carbon monoxide detectors, smoke detectors, and combination carbon monoxide and smoke detectors; Telecommunications hardware and software for monitoring and alerting remote sensor status via the Internet; Temperature sensors; Timing sensors; Ultrasonic sensors