ISO 18191:2026Published

Water quality — Determination of pHT in seawater — Method using the indicator dye m-cresol purple

Qualité de l'eau — Détermination du pHT dans l'eau de mer — Méthode utilisant l'indicateur coloré au pourpre de m-crésol

Abstract / scope

This document specifies a spectrophotometric determination of the pHT of seawater on the total hydrogen ion concentration pH scale. The total hydrogen ion concentration, [H+]T, is expressed as moles per kilogram of seawater. The method is suitable for assaying oceanic levels of pHT from 7,4 to 8,2 for normal seawater of practical salinity ranging from 20 to 40.

Life cycle

Replaces

ISO 18191:2015WithdrawnWater quality — Determination of pHt in sea water — Method using the indicator dye m-cresol purpleInternational Standard · Published 1 Sep 2015 · ISO/TC 147/SC 2