Teledyne API is a global leader in the design and manufacture of precision air quality and industrial gas monitoring instrume ... ntation. These instruments are used worldwide in ambient air quality monitoring systems (AQMS), continuous emissions monitoring systems (CEMS) and industrial process applications. Our instruments are used by government monitoring agencies throughout the world for regulatory compliance, including ambient particulate / gas and stack gas emissions, as well as process control in industrial applications. Located in San Diego, California, USA, Teledyne API is part of the Environmental Instrumentation segment of Teledyne Technologies Incorporated (NYSE:TDY). read more