The Environics® Series 4000 is a multi-component gas mixing system that automatically mixes up to three individual gases in a balance gas. The gas mixes can be used in generating precise gas calibration standards, creating gaseous atmospheres or producing gas mixes for analytical research or production purposes. The Series 4000 can produce gas concentrations from percent to ppb levels for single or multi-point calibration.      
      
The system consists of two components: the Series 4000 instrument and the user's personal computer. The user interface is a Microsoft® Windows application that communicates with the Environics system via an RS232 serial interface.      
      
The Series 4000 consists of a single chassis supporting up to four mass flow controllers. The mass flow controllers are factory calibrated using a primary flow standard traceable to the United States National Institute of Standards and Technology (NIST). Each flow controller utilizes an 11 point calibration table with linear interpolation, to increase accuracy and reduce flow controller nonlinearity.