When used as an adjective, “standard” does not take the plural “s”, whereas it takes it when used as a noun. The reason is that “standard” has been borrowed from the English language.

Even more confusing, MS Word does not know that, and the spellchecker (at least in the version I use) believes that “standards” is fine as an adjective, so many translators leave the mistake in their texts.

An easy way to remember is that nobody would use “standarde” or “standardes”, so why use “standards”?

Also, when “standard” is used as a noun in English, most of the time “norme” is a better french translation than “standard”.