How do you determine if a beauty product will irritate sensitive skin?

I got a set of Clairins beauty products and i need to know whether or not they will irritate my sensitive skin. Is there an ingredient that i should beware of ? I don't want to just TEST the products, if there's a way i can know beforehand i would appreciate it.|||I'm not sure about this, but you could always try puttng a little patch on your cheeks and see how that does.