What is chain of custody for a lab sample?
Chain of custody is a dated record of who handled a sample, from when it was taken from a lot to when the lab received it, so a result can be traced back to that lot.
What should a chain of custody record include?
The lot ID, the sample ID, who sealed the sample and when, who shipped it and how, and who received it at the lab and when.
Why does chain of custody matter for a COA?
Without it, you can't tell whether the sample the lab tested really came from the lot on your vial.
What is a tamper-evident seal?
A seal that shows visible damage if it has been opened, so the receiver can tell whether the sample was disturbed in transit.
What is a retain sample?
A sealed sample kept back from a lot so it can be retested later by the same or a different lab.
How does an independent retest work?
A sealed sample from the same lot is sent to a second lab, and the two lab-side records are compared, with the same lot ID on both.
Who creates the chain of custody record?
The party that takes the sample from the lot starts it. Each person who hands the sample on adds an entry, and the lab completes it when it logs the sample in and assigns its own sample ID.
What does a chain of custody form usually include?
A typical form has one row per handoff, with the date and time, who released the sample, who received it, the reason for the transfer and the condition of the seal. The lot ID and sample ID appear at the top so every row refers to the same sample.
What breaks a chain of custody?
A gap in the record, an unsigned or undated handoff, a seal that arrives broken or missing, a sample ID that doesn't match the lot ID, or a long unexplained delay. Any of these makes it harder to show the tested sample came from the lot on your vial.
Can a buyer see the chain of custody?
Some suppliers publish it with each lot record; others share it on request. If a supplier can't say who sealed, shipped and received the sample, treat that as missing information. A public record should show dates, roles and IDs, never a buyer's name, email or address.
Is chain of custody the same as lot traceability?
They overlap but are not the same. Chain of custody follows the sample from the lot to the lab. Lot traceability follows the whole lot, from production through testing to each vial that carries the lot ID.
How does Named Lot record chain of custody?
Check 6 of the Named Lot Standard requires a log of who sealed, shipped and received the sample, with dates and the sample ID. Products from the lot then move through recorded steps: reserved, labelled, shipped and received.
What should I ask a supplier about chain of custody?
Ask who took the sample from the lot, how it was sealed, how and when it was shipped to the lab, and what sample ID the lab assigned. A supplier with a real record can answer all four from the log.