Thanks TQ. This is useful but brief. I would explain more what I want.
Discrimination against religion in particular is seen differently in each country/workplace. In the UK and Canada for example, speech and writing against some religious beliefs is considered a hate speech. It is accepted for someone to wear anything that is based on his/her belief. It is a taboo to openly discriminate based on religion, even if hidden discrimination exists.
In the continental Europe, they see things differently. The employer can decide a "dress code" which automatically reject some groups. It is not seen as discrimination. They might see some habits (based on religion) as a disrespect to the country "culture".
In summary, some countries see it "do and wear what you want and you will not be disadvantaged based on it". Others see it "we do and hire whom we want based on out metrics which may include how do you wear or behave socially".
What I want is detailed rules emphasising what could be considered as discrimination in particular regarding religion.