BS / BS EN / EN / BS IEC / IEC confusion

Hi Chris,

It is perhaps good to understand the standards development process in order to appreciate the relationship between the standards. Each country has a standards body (BSI in UK) which has technical National Committees (NC) that report in to the international Technical Committees (TC) of IEC and CENELEC (for IEC and EN standards). These National Committees are the 'members' of the IEC/CENELEC TC.

Where a standard is produced in IEC there will be a decision on whether or not it is to also be embodied as an EN. If it is, then the CENELEC TC will not do any work on the standard (its member NCs will generally be members of both the IEC and the CENELEC TC so there is no need) and when the standard comes round to voting in IEC there will be parallel voting in CENELEC. Once a positive vote is received the IEC standard will be published and CENELEC will publish the standard a few months later as an EN, but they may add some technical annexes where it is deemed necessary due to European legislation (e.g. EU directives) which from memory are tagged on the end as Annex ZA, Annex ZB, etc. to distinguish them from any annexes the IEC may have included.

In other cases CENELEC may work on a standard themselves and produce an EN standard that has no IEC equivalent.

Once a standard has been published as an EN the National members of CENELEC are required, as members, to publish the standard unchanged in their own country. The only thing that can be added is a National Foreword. As an example, if there was an EN for plugs and sockets (which I think there is not because even in Europe there is no agreement) then BSI would need to publish this as a BS/EN unchanged, but could add a National Foreword saying "These plugs and sockets are not legal in the UK".

Where there is no parallel voting and therefore no EN then BSI are able (if they desire) to publish the IEC standard as a BS IEC so that they can get income from selling it rather than it having to be bought from IEC. These standards are unchanged from the IEC.

Therefore there is no difference between a BS IEC standard and an IEC standard. Similarly there is no difference between a BS EN and an EN standard (and if there is an IEC with the same number there is no difference with that either).

So to answer your question there will not be any discrepancies between them but if an EN standard is supporting an EU Directive it is probably better to use the EN version due to the European Annexes (either the pure EN or the BS EN).

If there is a pure BS (i.e. not BS IEC or BS EN) then it is not likely to have an international parent and may have requirements that are not reflected in any international standards.

I hope this helps.

Alasdair

Hi Alasdair,

Thank you for taking the time to respond, the information was very helpful. I shall share this back to the engineering team.

Following Brexit ,do you see this process changing ?

Also can you recommend any good books for some more background reading ? 

Regards

Chris

Alasdair Anderson said:

Therefore there is no difference between a BS IEC standard and an IEC standard. Similarly there is no difference between a BS EN and an EN standard (and if there is an IEC with the same number there is no difference with that either).

No quite. If there is a "BS EN IEC", the EN and IEC are identical,

If there is a "BS EN" and an IEC with the same number, there are (possibly only very minor) differences between the "EN" and the "IEC". This may be as little as some different national conditions agreed by CENELEC to those stated in IEC.

Chris Bailey said:

Following Brexit ,do you see this process changing ?

Many of the EN standards that we use are CENELEC standards, and the UK is still part of CENELEC, so for those you would expect to see no change. CENELEC standards are very clearly identified as such. The same for goes CEN standards. I can't actually think offhand of an EN standard I've come across in the day job that hasn't been from one of these two organisations. Of course in time we may see more BS standards generated separately, although personally I think this is unlikely at the moment.

Apologies for quoting Wikipedia, but actually these are very good articles!

CENELEC: https://en.wikipedia.org/wiki/European_Committee_for_Electrotechnical_Standardization

CEN: https://en.wikipedia.org/wiki/European_Committee_for_Standardization

Thanks,

Andy

The two bodies (CEN and CENELEC) along with ETSI for telecommunications standards are the only ones that can produce EN standards as they are the European equivalents of ISO and IEC producing non-electrical standards and electrical standards respectively. BSI are eager to remain part of CENELEC (and presumably CEN) and CENELEC are eager for BSI to do so. The only problem when I last looked into it was that to be a member a country needed to be part of the EU or part of the EEA, but the intention was that the Rules would be amended to try to permit UK to remain a member.

Graham,

You are quite right but I didn't want to further complicate it by introducing "BS EN IEC" to the mix. I think the only difference between an EN or BS EN (at least one drafted by IEC) and an IEC is the European Annexes - if there is a BS EN IEC it means that no Annexes have been added by CENELEC. Of course this is a simplified "idiots" guide to National and International Standards (written by an idiot...) so for a definitive answer we would need input from BSI.

Later edit.......

As I said above, written by an idiot. I have just visited the CENELEC wikipedia page, thanks to Andy's link below, and it seems the Dresden Agreement was updated by the Frankfurt Agreement in 2016, following which all IECs adopted by CENELEC have become EN IEC rather than just EN to clarify their provenance. You learn something every day. (These agreements formalise the relationship between IEC and CENELEC/ISO and CEN)

Alasdair

Thanks Alasdair, I really really ought to know this! Some bedtime reading for me sometime...as the OP says, the challenge is to find out where!