The Nuts and Bolts of Chemical Oxygen Demand   Water & Wastes Digest May 2003
Biochemical Oxygen Demand (BOD) is a definitive indicator of required treatment in wastewater, and estimating BOD is an important part of wastewater treatment process control. The U.S. Environmental Protection Agency (USEPA) requires wastewater treatment plants to bring BOD within limits before discharging treated wastewater, and accurate test results must be recorded for regulatory reporting. Thus, measuring BOD in treated water is an important part of the monitoring process. Many wastewater treatment facilities use a faster Chemical Oxygen Demand (COD) test to estimate BOD levels.