A recent door inspection in our building found that the glazing apertures were bigger than the test evidence data stated when they were installed a couple of years ago. The door inspector failed them & suggested new door set? Are new door sets required?

A new fire door-set is always preferable to a new fire door leaf-only in terms of suitability, compatibility and compliance.  Before you order your replacement check that the inspector has checked ALL evidence of fire resistance performance for the glazed door. Some manufacturers test with more than one provider and therefore it could sometimes be possible that additional data may exist.