สารละลายมาตรฐานความขุ่น 20 NTU

The HANNA® turbidity calibration solutions are produced according to the AMCO AEPA-1 standards, at 0, 10, 20 and 500 FTU.

They are preferred to the formazine based standards, as they are non-toxic, stable, reusable and long-lasting.