What is the purpose of the Chain of Custody (COC) in sampling?

The Chain of Custody (COC) is essential in sampling, especially in the field of occupational hygiene and environmental monitoring, as it serves to maintain the integrity and traceability of samples from the point of collection through to analysis and reporting. This process ensures that the samples remain uncontaminated and that their history is documented at every stage.

Maintaining a consistent chain of custody establishes accountability for the samples, as individuals handling them are responsible for their preservation and condition. This includes tracking who collected the sample, how and when it was collected, and all individuals who handled or analyzed it thereafter. This documentation is critical for ensuring that results are reliable and can hold up in legal or regulatory situations.

When samples are later analyzed, having a clear Chain of Custody allows investigators and stakeholders to trust that the procedures followed were rigorous and that the results reflect the actual conditions under which the samples were taken, rather than being influenced by mishandling or contamination. Hence, this procedure plays a pivotal role in the credibility of the entire sampling process and its outcomes.