Fatigue is probably the least appreciated impairment out there. The most dangerous aspect is that, long before your body shuts down, your judgement goes away.
I have seen many disasters happen simply because someone wasn't thinking clearly, and insisted on 'pushing on.'
I have what I call the "three strikes" rule...after a few 'stupid attacks' in succession- which may be something as silly as reading a tape measure wrong- I stop, take a break, catch my breath before I try again. The more major the 'stupid attack,' the more quickly I take that pause, and re-consider.
Unfortunately, I have seen a number of employers who have no understanding of thism and get mighty upset if they see you sitting down at other than the official break times.
There's more to safety than wearing a hard-hat.
