10 April 2018

UK standards

British standards (BS and CP)

There are seven types of British standards defined in BS 0 (A standard for standards – Principles of standardization):

  • Specifications
  • Management system
  • Codes of practice
  • Guides
  • Methods (test, specifying)
  • Vocabularies
  • Classification

These all carry the prefix BS and all have the same status and authority.

In the past, Codes of Practice carried a “CP” prefix; however, over the years they have been renumbered as BSs. That being said, there are still about 20 current codes that carry the old CP designation. Most are obsolete – which means they can still be used but are no longer being maintained by a BSI committee.

When a new British standard is published, an existing BSI publication bearing an identical number is automatically withdrawn unless stated otherwise.


BS EN publications (BS EN)

BS ENs are British standard implementations of English language versions of European standards (ENs). BSI has an obligation to publish all ENs and to withdraw any conflicting British standards after a period of coexistence (of up to 21 months). This has led to a series of standards which are designated as BS EN and use the related EN standard’s number.


BS implementations (BS ISO, BS IEC)

BS ISOs and IECs are comprised of the international standard’s text without any national deviation. The front and back cover indicate the UK committee responsible; however, no other information is normally added. The date referenced in the identifier is the date of the international standard.


Published documents (PD)

This category relates to standard type documents that do not have the same status as a BS. Some PDs are adoptions of CEN, CENELEC, ISO or IEC publications that are themselves not standards. Others are derived from British standards that conflict with ENs but are still needed by industry (e.g. PD 5500: Specification for unfired fusion welded pressure vessels). Others are developed by national committees but do not go through the development process or adhere to the strict conformity required for BS publications.


Draft Standards (DPC)

When a BSI committee has agreed a draft of a standard, it is published as a draft for public comment (designated as a DPC) and sold at a low price. People can then buy the draft and send any comments to the relevant committee for them to consider before the standard is finalised. The comment period is usually six months, after which the DPC is withdrawn.


Drafts for development (DD)

Occasionally, a committee is unsure as to the suitability of a standard, so it is published as a DD (which does not have the same status and authority as a BS). People can use the DD as they would a standard but are invited to feed comments back to the committee over a longer time period than a normal DPC. The intention is that the DD will eventually be withdrawn and replaced by a BS, but there is no set time period in which this must occur. For example, DD 2 was published in 1971 but wasn’t upgraded to a full BS until 2004 (BS 7935-1:2004, which has since been replaced by a BS ISO).

Some DDs are published as implementations ISO, IEC, CEN or CENELEC technical specifications (TS).


Publicly Available Specifications (PAS)

PAS are documents written by BSI in conjunction with external organisations and with a view to supporting certification schemes. The designation has been widened to include privately commissioned standards. PAS are generally fast track documents that serve to address issues in the interim between identifying a market need and proposing/developing a British or European standard.



Amendments and corrigenda

  • Amendments are issued when there is an alteration of or addition to an existing standard’s technical or editorial content.
  • When it is discovered than an existing standard has been inadvertently published with a mistake or is ambiguous, a corrigendum is issued.

While there was a time when it was standard practice to issue changes to standards as separate documents, nowadays, most are fully-incorporated into the standard. A new edition is issued and the old edition is marked as withdrawn. (See Updated British standards below). Changes that are issued separately are available free of charge on request to past purchasers of the standard, and all changes made to date are included within the main publication when purchased for the first time.


Updated British standards

In updated BSs, the amendments have been incorporated into a standard that is then issued with the same number but with an updated year.

Updated British Standards must be reordered as the amendments are not available separately.


British Standard Special Announcements

Proposed for confirmation

It is BSI policy for every standard to be reviewed by the responsible technical committee not more than five years after publication to establish whether it is still current and, if not, to identify and instigate appropriate action. Circumstances may lead to an earlier review. Proposed for confirmation means that the standard is about to undergo review.


Reviewed and confirmed

This designation means that the standard has been reviewed and is still deemed to be current by the reviewing committee. Confirmation includes all amendments published to date. Reference to a particular amendment indicates that it is published concurrently with the confirmation.


Declared obsolescent

Declaration of obsolescence indicates that the standard is not recommended for use in new equipment but needs to be retained for the servicing of existing equipment that is expected to have a long working life.



Withdrawn documents are classed as no longer current. This includes all amendments published to date. Usually, when a standard is withdrawn, information will be provided as to what document or documents replace the standard, as well as the reason for withdrawal if known. However, there are cases when the information hasn’t been shared by the relevant BSI committee.


Under review

To see if they should be confirmed, revised or withdrawn by the relevant UK committee.


New work started

The reference number of the committee responsible for each item of new work started is given. Where a work item has the temporary designation “BS EN XXXX”, it has not yet been allocated a standard number by the European standards body.


Draft for public comment

BSI hosts a draft review website where drafts are made available for comment. All comments are welcome, and will be considered by the relevant BSI committee. Draft standards may be modified before adoption and issue as British standards.


This article has been repurposed from a technical article originally written by NBS Information Specialist Stephanie Longmuir (and revised by Jess Sharman) for the Construction Information Service.