21 CFR Part 11 for vision systems: what to check before you buy

When Part 11 applies to a camera system

21 CFR Part 11 governs electronic records and electronic signatures that a regulated company keeps in order to satisfy a predicate rule. The test is simple: if the count, the inspection result or the evidence image is part of the documentation you rely on to release a batch, the system that produced it is in scope. The camera is not the regulated object. The record is.

Manufacturers in the EU meet the same expectations through EU GMP Annex 11 and the data integrity guidance that surrounds it. The vocabulary differs, but the technical controls a supplier has to provide are nearly identical, which is why one checklist serves both.

This is a practical guide rather than legal advice. Your validation lead and QA decide what applies to your process.

The seven controls to check

Work through these with the vendor in front of the running system, not the brochure. Ask for each one to be demonstrated.

• Unique identity for every action

  Every operator has a personal account, and the system can be tied to your directory service so joiners and leavers are handled once. A shared line login makes attribution impossible, and attribution is the foundation everything else rests on.

• A computer-generated audit trail

  Creation, modification and deletion are recorded with a time stamp and the user, independently of the operator, and the trail cannot be switched off without leaving a trace. Ask what happens to the trail when a setting is changed mid-batch.

• Records protected for their whole retention period

  Once a batch is closed it should be immutable, not merely read-only in the interface. Ask how the system detects a record that was altered in the database directly; a hash chain over the entries is one answer.

• Electronic signatures with meaning

  A signature captures who signed, when, and why (review, approval), and it is bound to the specific record. Re-entering credentials at the moment of signing is what separates a signature from a button.

• Copies you can hand to an inspector

  Both human-readable and electronic copies: a report that contains the results, the evidence images and the identities, plus an export of the audit trail that can be checked outside the system.

• Trustworthy time

  One documented time source, a stated time zone, and no way for an operator to move the clock. Time stamps that drift between the station and the rest of the line are a recurring audit finding.

• Documentation you can validate against

  A functional specification, a requirements traceability matrix and qualification protocols. Without them your team writes the vendor's documentation for them, at your cost.

Where vision systems usually fail the checklist

Machine vision grew up in general manufacturing, where the result is a pass/fail signal on a line and nothing needs to survive for ten years. That heritage shows.

• The result never becomes a record

  The count is written to a PLC tag and forgotten. Anything the line controller does not store is gone by the next cycle.

• Evidence images are not kept

  Without the frame the decision was based on, a deviation cannot be investigated afterwards. A number alone cannot be challenged or defended.

• The model is invisible

  Ask which model version produced a given result. If the answer is not in the record, you cannot show that a retrained model did not quietly change your process.

• Exports are editable

  A CSV in a shared folder is not a protected record. If the only output is a file anyone can open and save, the control has to come from somewhere else.

• Settings change silently

  A confidence threshold or an expected quantity changed mid-run, with no entry in the trail, invalidates every result after it.

Questions that separate a demo from a system

• Show me the audit trail entry for a settings change, including the old and the new value.

• Close a batch, then try to change a count in it. What does the system do, and what does the trail say?

• Export the audit trail and verify it outside the running application.

• Trigger a capture from the PLC. Which user is the result attributed to?

• Show me the report an inspector would receive, with images and signatures in it.

• Which documents ship with the system, and may we see the traceability matrix?

What this looks like in Steadeye

Steadeye was built from the record outwards, so the checklist above is close to its specification: personal or directory accounts, a SHA-256 hash-chained audit trail with a verification function, batches that become immutable when signed, signatures that require credentials and a meaning, PDF reports containing evidence images, and the model's SHA-256 recorded with every count it produced.

Validation itself remains yours. What a supplier can do is ship the qualification protocols and the traceability matrix so your team executes rather than writes them.