Calibration Standard HI 770 Checker HC ®

Range 0-999 ppb | ASTM Method D1687-92 diphenylcarbonate | Resolution 1 ppb

Range 0.0 - 8.0 ppm | DPD method | Resolution 0.1ppm

The HI 761 uses an adaptation of the USEPA method 330.5. The reaction between the chlorine and DPD reagent causes a pink tint in the sample.

Range 0:00 to 3:00 ppm NH3-N | Nessler Method | 0.01ppm resolution