WHAT DOES BIOLOGICAL OXYGEN DEMAND IN WATER MEAN?

BOD measurement requires getting two samples at each website. A single is tested right away for dissolved oxygen, and the next is incubated in the dead of night at 20 C for 5 days then tested for the level of dissolved oxygen remaining. The real difference in oxygen levels among the main test and the 2nd test, in milligrams per liter (mg/L), is the