Question:
Would the paid non Jewish security guard be allowed to use a wand (handheld metal detector) on Shabbos & yom tov?
Answer:
The security guard is being paid to make sure everyone entering whatever area he is securing is safe, and he is using the wand to help himself do his job. Therefore it is permitted for him to use it, because it is considered that he is doing the work for himself, and not for the Jew.
Best wishes
