What temperature range is suitable for refrigerating samples collected for BOD analysis?

The suitable temperature range for refrigerating samples collected for Biochemical Oxygen Demand (BOD) analysis is from 0°C to 4°C. This temperature range helps to preserve the integrity of the samples prior to testing. At temperatures below 0°C, biological activity can be significantly halted, which may affect the BOD results by preventing microorganisms from metabolizing the organic material present in the sample. Conversely, temperatures above 4°C could lead to increased microbial activity, resulting in a higher BOD reading than what would be accurate for the original sample conditions.

Refrigerating samples within this range strikes a balance that minimizes changes in decomposition rates and maintains the biological activity at levels that are representative of the sample's condition. This is crucial for ensuring that the BOD measurement accurately reflects the oxygen demand of the sample when it is finally analyzed.

Therefore, 0°C to 4°C is essential for proper sample preservation in BOD analysis.