While the parent ChainOfCustody has a collectionDate for the overall sampling event, collectedAt on a CoCRecord captures the well-specific collection timestamp. This is important for multi-well events where purging and collection extends across several hours — holding-time calculations that require time-of-day precision benefit from the per-well collectedAt rather than the event-level date. Record the actual time of sample draw, not the start of the site visit.
Technical section
Data model, API, and internals — visible to developers.