European standards are developed in the framework of CEN (European Committee for Standardisation).
On the CEN website, the Search Standards function allows you to search in the entire collection of published standards. You can search by English title, standard reference, document type, ICS, progress status and by committee. The results of your search may be displayed by Work Item number, standard reference or committee. The last column of the search results, 'Go to details', gives the national implementations of the standards, with links to the catalogues of the CEN Members.
If you click on the hyperlink and indicate in "Phrase in English title" the word "ventilation", you get the list of related standards.