Chemicals Inc CLEAR TURBIDITY STANDARD, 20 NTU

Clear turbidity standards are recognized by the EPA as a primary standard for the calibration of turbitidy meters online and in the laboratory for drinking water analysis. 
Clear turbidity standards are traceable to NIST Primary Standards on account of their consistent particle size and photometric accuracy via UV-VIS spectroscopy. 
Each lot is normalized to historical lots which were formulated to dilutions of 4000 NTU Formazin.

Chemicals Inc CLEAR TURBIDITY STANDARD, 20 NTU