What does the standard BOD test measure?

The standard Biochemical Oxygen Demand (BOD) test measures the amount of dissolved oxygen that microorganisms consume while decomposing organic matter in a water sample over a specified period, typically 5 days at 20 degrees Celsius. This test is crucial for assessing the organic pollution level in water, as it indicates how much oxygen will be depleted by bacteria as they break down organic materials. A higher BOD value suggests a greater amount of biodegradable material present, which can lead to oxygen depletion in the receiving water bodies, adversely affecting aquatic life.

The other answer choices refer to different measurements related to water quality but are not the focus of the BOD test. The total suspended solids pertain to solid particles that are not dissolved in water, while volatile solids relate to the organic portion of these solids. Chlorinated compounds are specific contaminants that can be measured but are not part of the BOD process. Thus, the essence of the BOD test is its role in understanding the oxygen demand exerted by bacteria on organic material, which is vital for wastewater management and environmental protection.