All Hanna solution bottles come with a pH Vs. temperature chart together with the production lot and expiration date to guarantee maximum accuracy.
Formulation Hanna pH buffers are made of potassium dihydrogen phosphate and disodium hydrogen phosphate and are standardized with a pH meter calibrated to NIST primary standard buffer solutions (NIST 186Ie & 186IIe and NIST 158 g S.R.M.).
