It depends Davo... and its hard to say without seeing the schools in question.
Take the example about the lack of maintenance on a fire alarm system in of the schools for instance.
Would I call this minor? I suppose my answer would be no, but then again it doesn't mean to say that the alarm system isn't working perfectly, or that persons have been put at serious or imminent risk. And clearly any resulting enforcement has to be geared proportionately to the failings found.
So "minor" is perhaps an unfortunate term, but in fire inspector speak it normally refers to issues where informal action has been issued instead of formal notices.
Plus I dare say they fire service spokesperson probably used that terminology to avoid dausing panic amongst parent (the article was originally produced for the local news paper "This is Lancashire").