There's been some writing about this, and the general advice to avoid this is to unplug the blender before clearing the blade. Which works, but is annoying enough that people don't consistently do it. On the other hand, most consumer ones come apart into two pieces for cleaning. There's the motor end, and the blade end:
If you take them apart, there's no way for a slip of your hand to pass power through to the blades. So here's a useful rule: always keep the parts separated unless the blade is in something you want to blend.
I counted 43 bands, 1,148 band bookings, and 3,518 musician bookings. Of those musician bookings, 29% (1,034) were women and 71% (2,484) were men.  The most common band arrangement by far was one woman and two men (11%), and here's the gender composition of these bookings charted:
In the room below, I set up my laptop (2017 MacBook Pro 15") with Audacity recording. I made sure ambient noise reduction was turned off, and I set the mic volume to 10%. I put the laptop on a pillow so it only would record vibrations through the air.
In the room above, I dropped a hammer onto a mat from a variety of heights. I used a "16oz" hammer, which weighed 23.9oz including the handle:
I dropped it head first onto a 0.5" EVA foam mat.
And here's our second floor: