ASTM D6697-01

This and other COD test methods are used to chemically determine the quantity of oxygen that certain impurities in water will consume. Typically this measurement is used to monitor and control oxygen-consuming pollutants, both inorganic and organic, in domestic and industrial wastewater applications.

For samples from a specific source, COD can be related empirically to BOD, organic carbon, or organic matter. The COD value is useful for monitoring and process control after this correlation has been established.

1.1 This test method covers the colorimetric determination of the quantity of oxygen that certain impurities in water will consume, based on the reduction of a manganese III solution under specified conditions. This standard method does not use characteristic heavy metal reagents, thus eliminating environmental and disposal concerns apparent in other methods.

1.2 This test method determines chemical oxygen demand colorimetrically using manganese III to obtain a visible color intensity inversely proportional to the chemical oxygen demand of the sample. Analytical test kits conforming to these methods are available commercially in ranges from 80 to 1,000 mg/L (ppm) chemical oxygen demand. It is the user's responsibility to ensure the validity of these test methods for their specific samples and matrices.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see Sections 9 and 12.