Nothing new about this, back in the 90’s we had to wear Hi Viz and hard hats on sites and in quarries while still in the cab. Even had to wear hats while doing surfacing work on Motorways etc, I suppose to protect us from falling aircraft? I remember wearing an orange coat with silver stripes that my brother gave me (a rail maintenance workers jacket) and the quarry manager telling me that it wasn’t allowed in the quarry as yellow was the recognized colour and I wasn’t visible enough to dumper drivers etc. I told him that if it was good enough for High speed trains seeing workers then dumper drivers should have no problems and anyway he spotted me easily enough, his reply was “I saw you because you stood out from the lads wearing yellow”!! 
Obviously not visible enough then?
Pete.