The Knigge Society, a "group that advises on social behavior and etiquette" says they have zero tolerance for kissing someone you work with on the cheek, unless you first create a sign that says it's cool with you:

It says it has received numerous complaints on the subject, and wants to remind Germans to stick with a handshake-and observe a "social distance zone" of 23 inches, reports the BBC. "We can't forbid [kissing in the workplace]," said the Knigge Society chairman. "But we have to protect people who don't want to be kissed."

The group, which has already given its recommendations on how to react to a runny nose in public, also suggests "that if people don't mind it, they announce it with a little paper message placed on their desk."