I think we have all had a brown trouser moment sometime in our lives whilst using machine tools, and no matter how much you push the 'nanny' safety precautions things, accidents will still happen (see below).
The biggest safety feature that can be used in a workshop, is COMMON SENSE. If it feels, looks, or even if it just makes you think about it being 'iffy', DON'T DO IT, it is as simple as that.
If you haven't got common sense, then you should be sitting in a rocking chair, knitting a new coat for the dog.
BTW, accidents don't happen, they are all caused.
Bogs