This is not prudent. Microwaves generate microwaves. The reason they beep that way, is theres a countdown timer to make sure it is safe to open the door. Obviously the dangers are not very high otherwise they would always lock, but if you will notice, there is also a lock feature.

So, it is more health conscious to way for all the beeps.

Also, the holes in the window are there, rather than full open glass, because microwaves are bigger than the holes, so they dont pass through.

This is the extent of my microwave knowledge.