The lot is the join key
A lot or batch number is the practical link between a physical container and its documentation. It should be captured exactly as printed, including prefixes or separators that distinguish otherwise similar records. Never silently normalize a lot number in a way that could merge two lots.
A good chain connects the label, order or receiving record, COA, analytical notebook, and final report. If one link is missing, mark the gap rather than guessing.
A minimal traceability record
At receipt, record the supplier, product name, lot, amount, date received, condition, and document location. When the material is used, copy the lot into the notebook or electronic record. When publishing a result, cite the same lot and the method version used.
- Label → exact lot string
- Lot → source COA or “available on request” status
- COA → report date and test method
- Experiment → lot, preparation, and operator record
- Result → method version and acceptance criteria
What a mismatch means
A mismatch does not prove the material is wrong, but it does mean the document cannot be treated as evidence for that container until the discrepancy is resolved. Contact the supplier or quality owner and retain the original records.
Sources and further reading
- NIST: Certificate of Analysis and Reference Materials ↗NIST explanation of certified values, uncertainty, traceability, and reference-material documentation.
- NIST: Quality System for Reference Materials ↗Quality-system context for reference material production and documentation.
- ISO/IEC 17025: Testing and Calibration Laboratories ↗Laboratory competence and record-control context.