This is one of the rules on my team's social contract.
If it's super urgent knock on their desk, if not, slack message them.
I have been startled several times by people either tapping me on the shoulder or waving their hand in front of my face.
This is an excellent rule.
We're a place where coders share, stay up-to-date and grow their careers.
We strive for transparency and don't collect excess data.