I would consider that you add a step before making a phone call or going and tapping somebody on the shoulder.

The thing that most threatens my zone is when the headphones need to come out. The _only_ exception is a simple yes/no, such as, "hey, want a coffee from Starbucks?" Anything bigger, whether a phone call or tap on the shoulder can really kill my session or workday. I'm talking your five minute conversation costing an hour or more of wasted time.

What do I recommend? Message me first and say "hey are you free to chat?"