Specifications include, but are not limited to: . range 0-100 PPB to 0-10 ppm, user selectable . precision = 1 ppb, . linearity MUST BE 1% of full scale. . rise and fall time of 20 seconds or less to 95%, . zero drift <1 ppb/7 days . span drift < 1%/ 24 hours / 7 days . Lag time <10 seconds . Flow Rate 800 cm/min +/-10% . Zero Noise 0.3ppb (RMS) / Span Noise <0.5% Additional specifications and requirements that MUST BE met. . operating temperature range covering at least 5-40 degreeC, . DC output range 0 to 1 volt, . The Calibrator MUST BE capable performing at least 40 independent calibration sequences that can be actuated manually, automatically or by a remote signal. . Temperature and pressure compensated. . MUST operate on an input voltage of 115 VAC 60 Hz. . Response time <180 seconds to 95%. . Lower Detectable limits 0.6ppb (RMS).