Biochemical Oxygen Demand (BOD)

Biochemical Oxygen Demand (BOD) is an important water quality parameter used to assess the level of organic pollution in a water sample that can degrade by aerobic biological action. It represents the amount of oxygen required by bacteria and other microorganisms to decompose the waste organically present in water.

In the formula, BOD is the Biochemical Oxygen Demand, D1 is the dissolved oxygen (DO) on day one, D5 is the dissolved oxygen on day five, and P is the decimal volumetric fraction of sample. This measurement is the difference in the dissolved oxygen consumed over five days at 20°C and is expressed in terms of milligrams per liter (mg/L). This test gives an estimate of the biodegradable organic matter present in the water.