most definitely, but if you have any intention on sticking your digits around the opening of an impeller, you’re best bet is to shut the damn thing down prior. But accidents still happen.
I almost lost a hand/fingers working on a customers Porsche 965 at the shop years ago. Bonnet was up, car running, and I tripped on tools on the floor walking towards the motor. Stuck my hands out to catch myself and lefty missed and damn near went right into the engine driven cooling fan on the motor. I was only 17-18 at the time too. Got lucky.
That guy right there: