What is the minimum acceptable temperature for storing water samples?

The minimum acceptable temperature for storing water samples is 39 degrees Fahrenheit. This temperature is crucial to ensure that the samples remain stable and maintain their integrity for accurate testing. Storing samples at temperatures that are too low, such as at freezing point (32 degrees Fahrenheit), can lead to the formation of ice crystals and alteration of the water's properties, which can affect the results of physical, chemical, and biological analyses. Conversely, temperatures that are too high can promote microbial growth or chemical reactions that can compromise the sample's quality.

Maintaining a temperature of 39 degrees Fahrenheit helps to minimize these risks, ensuring that the samples are suitable for further testing. It strikes a balance by being above freezing while also being low enough to inhibit unwanted changes to the sample during storage. This temperature is often recommended by testing protocols and standards to ensure consistency and reliability in the results obtained from the water samples.