Biochemical Oxygen Demand, commonly known as BOD analysis, is a chemical Procedure for determining the amount of dissolved oxygen consumed by aerobic Biological microorganisms in water. The analysis is carried out on a given water Sample at certain temperature over a specic period. The results are most Commonly expressed in milligrams of oxygen consumed per liter of sample at a Constant temperature of 20 °C during 5 days of incubation (BOD 5) Or during Complete oxidation obtained after a maximum period of 30 days (BOD ultimate). BOD analysis is widely used as an indication of the organic quality of water and the degree of organic pollution of water.