Chemical Oxygen Demand of Water (ASTM D 1252)

The ASTM D1252 test method determines the quantity of oxygen that certain impurities in water will consume, based on the reduction of a dichromate solution under specified conditions. Standard potassium dichromate solution oxidizes most organic and oxidizable inorganic substances in 50% sulfuric acid solution during refluxing. The dichromate consumed is measured by titration and used to calculate the COD value.

Total Organic Carbon in Water (ISO 8245)

The ISO 8245 international standard gives guidelines for the measurement of TOC concentrations in water from a variety of sources. A Shimadzu 5000 is utilized to perform the tests using high sensitivity platinum catalyst at high temperature to convert the carbon to CO₂, which is detected by an infrared detector. The linear range of the method is from 0.1 to 1000 mg/L organic carbon. Higher concentrations may be determined after dilution.

Free and Total Chlorine in Water (ISO 7393/2)

This colorimetric method utilizes a UV/VIS spectrophotometer at 510 nm and is applicable to concentrations of chlorine (Cl₂) from 0.03 to 5 mg/L total chlorine. For higher concentrations the test portion must be diluted.