These incidents bring up a pair of interesting points.
Code semantics aside ... how many fires will this guy need to have before he figures out he has a dust problem? Sawdust IS entering the equipment, and IS being ignited .... maybe he should address the dust issue?
It underscores the difference between 'code minimum' and 'good design.' Chances are, if the equipment was better placed it wouldn't have the dust accumulation.
We also see the results of 'make it work' attitudes. Why spend money on an expensive VFD, when you can simply bypass it?