Where to Smoke
Terminal 1: Gate D12 (Upper Level)
Terminal 2: Near Departures area
Terminal 3: Gates A2, A23, B7, B27, C9 and C23
Smoking is not permitted in any other public areas.
The Dubai Airport website indicates these areas are well ventilated and comfortable.
Below is the best I could find on maps.
Know more? Let me know in the comments.