My wife knows to wait. She’s afraid of distracting me. Still, there’s nothing like turning around and seeing someone materialize from out of nowhere.
I’ve even thought of turning EVERYTHING in my shop around so I face the door running the table saw, band saw, jointers, stationary sanders, pin router and so forth just to avoid being startled.
As someone else suggested, a sensor and a bell wouldn’t be a bad idea either. I just happen to have one I picked up yard saleing.