The purpose of the highlighter-yellow vest is to make APPROPRIATE people CONSPICUOUS. Thus it was easy to identify Incident Commanders, Marshallers or Security Personnel from amongst everyone else at the aerodrome. But some idiot in the H&S nanny world couldn't understand that as a basic principle and thought that they were some sort of airside safety armour. So now everyone is supposed to wear the damn things and it's hard trying to pick out CRUCIAL personnel when you need them. The yellow bib is being used ENTIRELY INCORRECTLY by most aerodrome operators; what is needed is some common sense to be re-applied to this subject!