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R9 Laboratory SOP 545
DETERMINATION OF SPECIFIC CONDUCTANCE
Summary
This method is applicable for drinking, ground, surface, and saline waters, domestic and industrial wastes and acid rain (atmospheric deposition). This SOP is based on EPA Method 120.1.
Conductivity is reported as micromhos/centimeter (umhos/cm).
Conductivity is a numerical expression of the ability of a water sample to carry an electrical current. This number depends on the total concentration of the ionized substances dissolved in the water and the temperature at which the measurement is made. The mobility of each of the various dissolved ions, their valences, and their actual and relative concentrations affect conductivity.
The specific conductance of a sample is measured by use of a self-contained conductivity meter, Wheatstone bridge-type, with automatic temperature compensation (ATC).