PDF Picasso is free from Drawing revision codes explained: P01, C01, S2
Updated 26 October 2026 · from SiteHelm
On most UK projects a drawing carries two codes in its title block: a revision (P01, C01) and a status (S2, A1). Together they tell you whether you can build from it.
Revision codes
The codes come from the UK National Annex to BS EN ISO 19650-2, explained in the UK BIM Framework’s guidance.
- P means preliminary: shared for coordination, information or comment, but not contractual. P01, P02, P03 and so on as it develops.
- C means contractual: published, and the version to work to. C01, C02 and so on for each published revision.
- A number after a point, such as P01.05, is a work-in-progress version inside the design team. You shouldn’t normally see these on site.
Status codes
| Code | Means | Build from it? |
|---|---|---|
| S0 | Initial status, work in progress | No |
| S1 | Suitable for coordination | No |
| S2 | Suitable for information | No |
| S3 | Suitable for review and comment | No |
| S4 | Suitable for stage approval | No |
| A1, A2… | Authorised and accepted (the number is the project stage) | Yes, for that stage |
| B1, B2… | Partial sign-off, with comments | Only as the comments allow |
| CR | As-constructed record | A record of what was built |
Projects can add or leave out codes in their own information standard, so check the project’s list if you see one that isn’t here.
On site
- Work to the latest C revision with an A status. If all you have is a P revision, ask before building from it.
- When a new revision arrives, cloud what changed on the old one or check the revision box, then take the old copy out of use.
- Keep one current set. In PDF Picasso, Combine drawing sets keeps only the latest revision of each drawing and adds a contents page.
Sources
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