An air gap exists for one purpose: to protect you from your own plumbing. It’s a cheap, elegantly stupid solution that never fails because it has no moving parts. It’s just a breath of fresh air.
So next time you’re brushing your teeth and see water fall through empty space, smile. That invisible gap is your best friend. And please, never dip your toothbrush in the sink water.
Your mouth will thank you. And so will your plumber.
