Biochemical Oxygen Demand (BOD) is the amount of oxygen required (in ppm): (1) by

Biochemical Oxygen Demand (BOD) is a measure of the amount of oxygen required to break down both organic and inorganic waste present in a certain volume of water. (1) Anaerobic bacteria require oxygen for the breakdown of inorganic waste in a water body. (2) Photochemical processes require oxygen to breakdown waste present in a volume of water. (3) Bacteria require oxygen to break-down organic waste in a water sample. (4) Oxygen is also essential for sustaining aquatic life in a water body. The BOD test measures the amount of oxygen required in ppm (parts per million) to break down these wastes.