A strange question to ask but one that was posed to me earlier this month – So “When is ISO 14001 not ISO 14001?”
Most people reference the International Standard as ISO 14001. Although, it is better to refer to the International Standard by the more, correct format of ISO 14001:2004, so that the year of publication (2004) is reference to distinguish this current version from the earlier version dated 1996. ISO 14001:2004 should be used for the first formal reference and thereafter simply called ISO 14001.
However, the more correct presentation within Europe is XX EN ISO 14001:2004, where XX represents the national standard reference.
For the United Kingdom, it would be BS EN ISO 14001:2004, where BS shows that it is approved by BSI as a British Standard, EN as it is approved as a European Norm (Standard).
Similarly in Germany, it would be DIN EN ISO 14001:2004 as DIN is the German equivalent of a British Standard.
Additionally, I have seen some certification bodies using a further additional reference “/Cor. 1:2009”,
This reference is to the Technical Corrigendum 1 published on 15 July 2009, which made a minor amendment to Page iii in the Table of Contents and Page v, Introduction, sixth paragraph, last line to replace the reference to ISO 9001:2000 with ISO 9001:2008.
It should not be necessary to reference the Technical Corrigendum 1 in the quoting of the International Standard as it has no impact on the EMS specific requirements but some may consider it to be the ultra-formal expression of ISO 14001:2004.
Whichever format you use, all are correct depending on the context – Use each according to the guidance above and you will not be wrong.