Sampling & Chain of Custody
This section covers the path from a field sample to a documented lab handoff: you record each Sample a crew collects, then build a Chain of Custody (CoC) that lists the samples shipped to a lab, the analyses requested, and the sequence of custody transfers. Samples and chains of custody both belong to a Project, and field samples are anchored to a Location.
In this section
- Samples — what a Sample is, its identification, classification, location, and temporal fields, the Sample Type and Status values, and how parent/child samples link by code.
- Record a sample — record a sample under a project: enter its Code, Matrix, Sample Type, collection date, and (for field samples) location, depth, and coordinates.
- Chain of Custody — what a CoC documents: header snapshot fields, the samples and analyses it carries, custody transfers, the Status lifecycle, and the printed CoC form.
- Create a chain of custody — build a CoC for a lab handoff: add samples, list requested analyses, assign analyses to samples, log transfers, and print the CoC as a PDF (Print COC).
How it fits together
A Sample is an aggregate root owned by a Project and (for field samples) scoped to a Location. A Chain of Custody is a separate Project-scoped record that references samples through its own child rows — a Sample carries no link back to the CoC, so one Sample can ride several chains of custody to different labs.
Figure: A Project owns both Samples and chains of custody; a CoC references Samples through its own sample rows.
Field samples cover the values written on a field form — matrix, type, collection time, depth, and coordinates. Laboratory results for those samples are recorded separately under Laboratory Data. Per-container detail records are not part of this release; a CoC sample carries a single Container Count instead.