Every drawing that reaches site carries two answers in its title block. Which issue is this? And what is it for? The first is the revision code. The second is the status code. Get either wrong and someone builds to the wrong sheet, or builds to the right sheet before it was meant to be built from.
This page explains both as they're set out in the UK National Annex to BS EN ISO 19650-2, the standard UK projects use when they work to ISO 19650. Your project's own information standard has the final say. It's the document that tells you what each code means on that job and it can add to what's here.
The short version
- P revisions (P01, P02, P03) are preliminary. They're shared for coordination, information, comment or approval. They aren't contractual.
- C revisions (C01, C02) are contractual. A C revision is information that has been authorised and accepted and published.
- S status codes (S0 to S5) say why a preliminary sheet has been shared.
- A status codes say a sheet has been authorised and accepted. What each A number means (construction, for example) is set by the project, not the standard.
- When a new issue of a sheet is published, the earlier one is superseded. It isn't deleted. It's kept on the record, but nobody should be building from it.
Revision codes: P and C
The UK National Annex uses a letter and two digits.
| Code | Meaning | Where you'll see it |
|---|---|---|
| P01.01, P01.02 | Work in progress versions inside the team producing the drawing | Their own work area. You shouldn't normally receive these. |
| P01, P02, P03 | Preliminary revisions, shared with other teams | Coordination, information, review and comment, approval |
| C01, C02 | Contractual revisions, authorised and accepted | Published information, the issue the contract relies on |
The C stands for contractual. It's often said to mean "construction" or "complete", and that's worth correcting, because a C revision isn't automatically a construction issue. What it's suitable for is in the status code beside it.
The work in progress suffix uses two digits after a full stop (P01.01, not P01.1). It drops away when the drawing is shared, so the first shared issue is simply P01.
Status codes: what the sheet is for
The status code (many people still call it suitability, which was the BS 1192 term) says why the drawing has been shared or published. These are the codes in the 2021 version of the UK National Annex.
| Code | Meaning | What it means on site |
|---|---|---|
| S0 | Initial status: work in progress inside the team producing it | You shouldn't have it. Ask where it came from. |
| S1 | Suitable for coordination | Shared so other designers can coordinate with it. Not for building from. |
| S2 | Suitable for information | Shared so you know what's coming. Not for building from. |
| S3 | Suitable for review and comment | Shared for your comments. Not for building from. |
| S4 | Suitable for review and authorisation | Shared so the lead appointed party can authorise it before it goes to the client. Not for building from yet. |
| S5 | Suitable for review and acceptance | Shared so the client (the appointing party) can review and accept it. Not for building from yet. |
| A1, A2, A3 and on | Authorised and accepted | Published, with a C revision. The project's information standard says what each A number means. One of them is usually the issue for construction. |
| B1, B2 and on | Partially authorised or accepted, with comments | Comments still to be addressed. Under the 2018 annex these travelled with a P revision. Check whether your project uses B codes at all. |
The S codes all travel with a P revision. The A codes travel with a C revision. If you see an A status on a P revision, or a C revision with an S status, query it before using the sheet.
The plain rule for site is this. Build from published information with the A code your project uses for construction, unless you've been instructed otherwise in writing. An S2 sheet that "everyone knows is right" is still a sheet issued for information.
What changed in 2021
The UK National Annex was revised in February 2021. The standard itself didn't change; BS EN ISO 19650-2:2018 is still the current edition. But the annex changed several status codes and it's why two people on the same job can read S4 differently.
| Code | 2018 annex | 2021 annex |
|---|---|---|
| S4 | Suitable for stage approval | Suitable for review and authorisation |
| S5 | Withdrawn, not used | Suitable for review and acceptance |
| S6 | Suitable for PIM authorisation | Withdrawn |
| S7 | Suitable for AIM authorisation | Withdrawn |
| A codes | Authorised and accepted, with each A number tied to a project stage | Authorised and accepted, with each number's meaning set by the project's information standard |
| CR | As-constructed record | Withdrawn. The project defines an A code for it instead. |
If your appointment documents were written against the 2018 annex, the 2018 meanings are likely to apply on that job, and older projects often were. Your appointment and the project's information standard decide. It's worth checking which annex your project's information standard refers to before you argue about an S4.
Why people still say BS 1192
BS 1192:2007+A2:2016 and PAS 1192-2:2013 were the British documents for producing and sharing construction information. Both were withdrawn in January 2019, when BS EN ISO 19650-1 and BS EN ISO 19650-2 were published in the UK with the UK National Annex.
A lot of the vocabulary carried over, including the idea of a common data environment, file naming fields and suitability codes. So "BS 1192 naming" and "BS 1192 codes" are still how many people describe them, and plenty of templates still have BS 1192 in the footer. It doesn't matter much in conversation. It matters when you're relying on what a code means, because the meaning comes from whichever document your project actually adopted.
ISO 19650-2 is being revised and the draft also replaces Part 3. It hasn't been published: in August 2026 ISO recorded a decision to hold a second draft ballot. Until a new edition is out, the current ones stay in force (Parts 1 and 2 from 2018, Part 3 from 2020). Expect this page to change when it is.
What superseded means in practice
When C02 of a sheet is published, C01 is superseded. In a common data environment the earlier issue moves to the archive state. It's kept, with its history, because it may be needed to show what was built or what changed. But it's no longer the current issue.
On site, superseded needs more than a status in the system. In practice:
- Take superseded prints out of the site office, the welfare cabins and the work face, or mark them clearly as superseded.
- Update the drawing register so the current revision is the one people look up.
- Tell anyone who set out, ordered or fabricated from the earlier issue. They're the ones a revision costs.
- Keep a copy of the superseded sheet with the date you stopped using it. If a dispute comes later, you'll need to show what you built from and when it changed.
The drawing register
A drawing register is the list of every drawing on the job and its current issue. It's how anyone on site can check, in seconds, whether the sheet in their hand is the latest.
As a minimum, it should show the drawing number, title, current revision, status code, date of issue, who issued it and where it was distributed (often by transmittal reference). A register that also lists earlier revisions and the date each was superseded answers the question that comes up in every dispute: what was current on that date?
A transmittal is the record that goes with an issue. It says which drawings, at which revision and status, went to whom and when. If a revision arrives without one, ask for it. It's your evidence of when you received the change.
One drawing's life, start to finish
This is an illustrative example. Your project's codes for each step may differ, especially the A numbers.
| Issue | Status | What's happening |
|---|---|---|
| P01.01, P01.02 | S0 | The designer is working on the sheet. Nobody outside their team sees it. |
| P01 | S2 | Shared with the contractor for information, so they can see what's coming. |
| P02 | S3 | Revised after coordination and shared for review and comment. The contractor comments on buildability. |
| P03 | S4 | Comments addressed. Shared for authorisation by the lead appointed party. |
| P03 | S5 | Authorised, and shared with the client for review and acceptance. |
| C01 | A (construction) | Authorised, accepted and published. This is the issue the site builds from. |
| C02 | A (construction) | A design change after construction issue. C01 is superseded. Someone needs to check what was already built or ordered to C01. |
The step that goes wrong is the last one. A new C revision arrives, gets filed and nobody compares it properly with the one the site has been working from. That's what the revision review checklist is for.
Sources
- UK BIM Framework, Information management according to BS EN ISO 19650, Guidance Part C (status and revision codes under the 2018 National Annex)
- UK BIM Framework guidance hub
- Centre for Digital Built Britain, press release on the revised UK National Annex (19 February 2021)
- GlobalCAD, ISO 19650: the UK National Annex updates (summary of the 2021 status code changes)
- projectdesign.io, comparison of status codes between the 2018 and 2021 UK National Annex
- ISO, ISO/DIS 19650-2 edition 2 (development status)
- nima, proposed changes to ISO 19650 (BSI and nima webinar)
The National Annex itself is published by BSI and isn't free. If your project relies on a code's exact wording, read it in the annex your appointment names. Last checked 13 October 2026.