Dated references in harmonised standards

Dated references in harmonised standards

Informative paper on

Dated references in harmonised standards

Which version of the supporting standard has to be used to determine the durability of a product or its characteristics for CE-marking?

  • If, in the clause 2 of the harmonised standard, the reference to the supporting standard is dated, only this version shall be used
  • If, at the contrary, this reference is undated, the last version shall be used.


Implementation of harmonised standards

A harmonised standard is a European standard developed by a recognised European Standards Organisation: CEN, CENELEC, or ETSI. → For the glass in building standards, the European Standards Organisation is CEN, and the technical committee is CEN TC 129, glass in building.
A harmonised standard is created following a request (formerly called “mandate”) from the European Commission to one of these organisations. → For the glass in building standards, it is the Mandate M/135.
Manufacturers, other economic operators, or conformity assessment bodies can use harmonised standards to demonstrate that products, services, or processes comply with relevant EU legislation. → For construction products, the relevant EU legislation is the Regulation (EU) No 305/2011 (Construction Product Regulation or CPR).

The references of harmonised standards must be published in the Official Journal of the European Union (= OJEU). Two important dates are fixed by this publication in the OJEU. These dates are the same in all countries where CE-marking is applicable.

1. The date of applicability of the standard as a harmonised standard


→ This is the date on which the CE-marking of a product covered by this harmonised standard can start
2. The date of the end of the coexistence period, also called Date of Withdrawal (DOW).


→ This is the date on which the CE-marking of a product covered by this harmonised standard is mandatory. This is generally 1 year after the date of start.
The coexistence period is the period of time during which:

►   possible national standards on the same subject can still be used (in case no European harmonised standard was existing before), or

►   the previous version of the standard is still applicable when the harmonised standard is a revised version of an already published and cited one.

→ The coexistence period is necessary to perform the required tests, calculations, etc., and to prepare the new or (when relevant) revised Declaration of Performances for CE-marking.

Only the harmonised standards are cited in the OJEU. They cannot be used before the date of applicability and must be used from the Date of Withdrawal. But the standards that are not harmonised standards are not following this rule.

  • If they are referred to in a standard as undated reference, the last version has to be used.
  • If they are referred to in a standard with a dated reference, this reference is the only one to be used EVEN if this version has been superseded in the meantime.

Structure of the standards on glass in buildings

The standards prepared by CEN TC 129, glass in building, have always the same structure:

►   one or several parts dealing with the requirements, test method(s) or calculation procedure(s), tabulated values, etc.,

►   one harmonised part, fully compliant with Regulation (EU) No 305/2011 and with the template for harmonised standards provided by CEN. → This is the only part that is cited in the OJEU.



In order to avoid being obliged to implement the other parts at the date of their publication, in other words, to benefit for this coexistence period allowed for by the system of citation, all parts of the same standard are referred to as dated reference.

In that way, the new version of the non-harmonised part(s) of a product standard is mandatory ONLY from the Date of Withdrawal given with the citation of the corresponding harmonised part.


In EN 14449:2005, the normative references to EN ISO 12543 parts 1 to 6 are dated 1998.

Although a revised version of these 6 parts of the standard has been published in 2011, they are still not applicable as no revised version of EN 14449 has been published and cited since then.

No type test or test reports according to EN ISO 12543: 2011 can be required by market surveillance authorities, clients, controllers, etc. Only the harmonised standards are cited in the OJEU. They cannot be used before the date of applicability and


What happens if the reference to a supporting standard is not dated?

In the harmonised standards of CEN TC 129, many standards references are undated. This means that the latest version applies whatever its date of publication.
This may create problems when testing or calculations need to be redone.EN standards are not sold by CEN but by National Standardisation Bodies.
When they receive from CEN the definitive text of the standard in the official language versions (English, French and German), they have 6 months to publish them.
This timeframe doesn’t apply for the possible translations in another language.
→ The date CEN is sending the definitive text of a standard to National Standardisation Bodies is indicated on the front page of the standard (month + year).

As National Standardisation Bodies have 6 months to publish the standard, we can reasonably consider that compliance with the new version cannot be required before the end of this delay.

This date is referred to as “date of withdrawal” on the CEN website, on the page related to each standard (see