What's being a member of a Union got to do with it ?
Are Union members exempt from this nonsense ?
It is up to the employer to guarantee that anyone that they give a 'swipe' card to, and therefore Airside access, is indeed a bone fide employee, and they can introduce as many security checks as they like before accepting one for engagement and issue a pass, if the individual, or the Union, don't like it - next please.