As industries evolve, standards must adapt to remain effective and applicable. 

Regular updates ensure that standards align with technological advancements, regulatory changes, and industry best practices. Here are five different ways a standard may be altered, and the terms used to indicate that a change has taken place:

1.  Amendments (AMD)

If you see +A1 on a standard, this means the standard has been amended at some point. Dates for any amendments can be found in the National Foreword of a standard

An amendment can be considered as any alteration or addition to previously agreed technical or editorial content of an existing standard, and can take anywhere from six to twelve months to produce.

The amended version of a standard will usually supersede the existing standard and remove conflicting provisions in pre-existing national standards. Additional amendments within a standard series will progress to amendment +A2, +A3, and so on, until a new technical editorial standard revision is published.

If the revision then requires amending, the process will begin again, with the first amendment being published as +A1.

2. Corrigendum (Cor)

When Corrigendum(a) is mentioned within a standard, it signifies an alteration and/or an addition to a standard. The purpose is to correct inadvertent errors or ambiguities that have been noticed since a standard’s publication.

The corrigendum is solely used to correct errors or ambiguities that could lead to incorrect or unsafe application of the publication. Trivial errors will usually be left uncorrected until the need for a more substantial amendment arises.

Corrigenda can take up to six months to produce. Issue dates can be found in the National Foreword of a standard, documented as ‘Corridenda 1.’ in the AMD (Amendment) field. The National Foreword will also advise which Corridenda have been incorporated into the standard.

3. Errata

This means that a correction has been made to a document. It is a list of errors and corrections and is treated as a Corrigendum.

4.  National Annex (NA)

This provides guidance on the application and applicability of a European or international standard. A National Annex is usually published within the National Foreword of a standard, usually beginning with the phrase: “This British Standard is the UK implementation…”

Any information that the committee believes will support the use of an adopted standard in the UK will be published in the National Foreword as a National Annex.

5.  PD ENV

This indicates a draft for the development of a European publication. PD is a published document of national origin, which takes roughly nine months to produce. ENV is the European version of a pre-standard (draft). A document in the draft process does not achieve standard status until the full publication process is complete.

What are the periodic standard revision cycles? 

Beyond specific amendments and corrections, all standards undergo regular review cycles to assess their continued relevance.

Most standards are reviewed every five years under a process known as a systematic review. If a standard is still relevant, it remains unchanged. If updates are required, the standard may be amended, revised, or withdrawn.

Any questions?

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