Calibration Standard HI 706 Checker HC ®

Range 0.00 - 9.99 ppm NH3-N | Nessler Method | 0.01ppm resolution

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 - 200 ppb | ascorbic acid method | Resolution 1 ppb