Which item on the sample container label helps identify when the sample was collected?

• A. Time and date of collection
• B. Test to be performed
• C. Plant name
• D. Location of sample

Answer: (A)

Knowing when a sample was collected is essential because the time and date stamp on the container ties the result to a specific moment in the process. This timestamp allows you to verify that the sample is being analyzed within its required holding time and provides clear traceability for the lab’s records. It also helps interpret results in the correct context, such as aligning with the plant’s operating conditions, influent characteristics, or flow at the moment of collection.

Other label details serve different purposes—what test will be performed, where the sample came from at the plant, or the exact location within the site—yet none of those tell you when the sample was taken.