What does the message “Caution: Sample not returned within Manufacturers Maximum recommended Holding Time” mean?
Most chemicals are not stable on sampling media indefinitely. There is a length of time between sampling and analysis where the accuracy of the result might be affected due to chemical breakdown, reverse diffusion, etc. Based on storage stability data for a particular monitor, samples that arrive back to the lab after the recommended holding time has been exceeded are flagged with a note to use the data with caution. In many cases, it is not possible to determine exactly how much the results have been affected. However, a badge that should have been returned within a week, but was stored in a freezer for 2 weeks before it arrived at the lab will be less affected then a badge that was stored for 2 weeks in an unconditioned warehouse in the summer. Recommended holding times are listed on the technical inserts included with all Assay Technology products. They are also available online.
