A standard is a technical document designed to be used as a rule, guideline or definition. It is a consensus-built, repeatable way of doing something. Standards are created by bringing together all interested parties such as manufacturers, consumers and regulators of a particular material, product, process or service. 

The EN standards are drafted and voted within the CEN (European standard entity). Any company can be member of the CEN and propose new standard and participate in the drafting.

A standard does not have any legal purpose and in the case of the EN15194 and EN17860 the manufacturer certifies himself  its bike with the support or not of a third party