This document specifies the performance requirements and the test procedures for a pH meter used for continuous on-board monitoring using combination electrodes. The pH meter applies to measuring the pH of the following water for on-board consumption and research purposes:

a) natural seawater and freshwater,

b) freshwater produced from freshwater generators,

c) the used process water for running machinery on-board ships.

This document also specifies the method for evaluating performance, calibration, and maintenance of a pH meter used for continuous on-board monitoring.