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Combined Interpretations of the 2003, 2009, and 2016 Standards that apply to Volume 1 of the 2016 TNI Standard

Section: 5.8.8

Question:  We needed samples of drinking water to be tested for lead. I was disturbed to see a lab did not have a chain of custody form. I was concerned that there was an unsigned gap in the chain of custody when samples were delivered by FedEx courier to a lab nearby. The question is: isn't a complete continuous, signed Chain of Custody form required so the sample could be accounted for specifically by a signed individual?

TNI Response:  A complete, continuous Chain of Custody form is not required for samples, unless otherwise specified by the client. Note that 5.8 differentiates between sample handling and tracking and legal chain of custody protocols.  5.8 requires that a record keeping system allow historical reconstruction of all laboratory activities. A laboratory that does not record the receipt of samples by a specified individual is not compliant with this aspect of the standard.