Larry Isaacson's nose is so sensitive to perfume that he gets woozy, loses his appetite and can develop an itchy rash that blooms behind his ears when he is exposed to it. So when a colleague recently slathered on perfume that emanated well beyond her personal space, Mr. Isaacson found himself employing his usual tactics. They include avoidance, which means standing several feet away from the cloud and holding his breath until it passes. If trapped in close proximity for an extended time, he breathes through his mouth. And his most passive tactic, which sometimes works best: waiting for someone...