Is explicit revision control needed if handled automatically by software?

Mark Meer

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If an electronic documentation system automatically handles certain "cascades" of document changes, is explicit approvals/revision-levels required for the documents that are automatically updated?

For example bill-of-materials (BOM) and device master records (DMR) are created automatically based on current revision of other controlled documents (they are essentially just indices which tabulate part-info/documents from the meta-data of other files).

So, in practice, if a part-drawing is updated, the BOM and DMR are automatically updated by the document management software. In this case it seems unncessary to have to explicitly document revisions and approvals of the new BOM and DMR...



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Do it however works for you - it sounds like what you're doing actually does constitute " revisions and approvals ".

But bear this in mind - I speak from experience.

The first time the system glitches and you're unable to detect at exactly what point the glitch began, you'll wish you had a more thorough control system.

Mark Meer

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:lol: Thanks normzone. Knowing how volatile all-encompassing electronic systems can be, I frequently export and backup PDFs as "snapshots" of the files at a given point in time...
These are exclusively backup and are not available to others (so there is no mixup). The "official" versions of BOM and DMR are accessed purely electronically and are generated in real-time by the software... sounds like what you're doing actually does constitute " revisions and approvals ".

That's the thing: using a system like this, neither the BOM nor the DMR actually have a revision or explicit approvals, as they are generated by the software on demand...

Anyway, seems to be working well. I was just concerned that generating documents in real-time by the software may be questioned by quality-system auditors...


Does everyone that has the ability to modify any controlled element, have full authority on their own to change that element? Or is there some sort of implied change approval or authority assignment external to the change control system?

How does your quality system handle matters that require more than one approval before implementation?

You use the term "DMR", implying US FDA compliance is an issue. I doubt if a system such as you describe could be made to satisfy an inspector in regard to 21CFR 820.30 Design Control unless there's more to it, because of the expectation of multiple approvals for certain design commitments, which implies multiple approvals for controlled changes subsequent to those commitments.

It's common in my experience for a medical device controlled-change pre-approval process for a significant change (as opposed to a defined-non-significant change or document correction) to require six or eight signatures.
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Sounds like a potential risk to me. What if a drawing (or whatever) is updated and approved but not intended to be incorporated into an assembly until a later time? Will the software automatically generate the BOM and DMR based on this?

Do you at least somehow snapshot the BOM and DMR after they are produced? Otherwise, how do you know what the configuration of a particular lot was built against? I presume there's more to the story but those thoughts jumped out.


how do you know what the configuration of a particular lot was built against?

Yes, crucial point. My understanding is that a system that doesn't maintain a history of all its revision levels, with effectivity dates for each approved change and an ability to tie each production batch to the DMR status under which they were other words, a DHF and DHR...cannot satisfy 21CFR 820.

Or do you intend to do those functions and the change approvals process offline using paper?

Mark Meer

Trusted Information Resource
Thanks for all replies. Good discussion.

Perhaps an example would help illustrate:

1. A draft of a new part drawing is issued by engineering (in response to a change-request)

2. Any verification and/or validation required for the change are carried out and documented in the change record. Following these activities, the new part drawing is formally approved by all necessary parties via a paper-based sign-off.

3. Once approved, the new drawing made effective by uploading to the electronic system. The electronic version is read-only (except to system admin, who is responsible for uploading approved revisions).

4. Now, if you were to re-load the pages for the DMR or BOM, they'd be automatically updated with the details of the revised drawing.

5. In terms of Device History Records, when a batch is started, the DMR and BOM are brought up and printed, and these printed copied are maintained with paper-based DHRs. ...this way it is certain what the "snap-shot" of the DMR and BOM was for any given production batch.

So, despite the fact that neither the DMR or BOM have an explicit revision, change-history or approvals (except for approval of the initial template):
- It is clear what the state of the two are for each production batch.
- The electronic versions are always up-to-date, as they index other document data in real-time.
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