Question

Limit of BOD prescribed by Central Pollution Control Board for the discharge of industrial and municipal waste waters into natural surface waters, is -

• A. < 3.0 ppm
• B. <10 ppm
• C. < 100 ppm
• D. < 30 ppm

Answer 1

The correct option is B <10 ppm

BOD is Biological oxygen demand. It is the total amount of oxygen required by the microorganisms present in a water body to break down the organic matter. If BOD is more, it means that there is abundance of microorganisms in that water body and hence it is polluted with organic matter.

Water with BOD level 1 - 2 ppm is considered to be good water, if the BOD is 3 - 9, then the water is considered to be slightly polluted, and if the water has BOD more than 100 ppm, then the water is greatly polluted.

The Central Pollution Control Board has prescribed the limit of BOD for the discharge of industrial and municipal waste in order to regulate the water pollution and for efficient water treatment, and it is <10 ppm.