Gas.
Guess I picked an ideal day to be home sick:
Subject: Gas odor
A gas line has been broken in the new college construction area. The fire department has been called and is on the scene. In the meantime, the fresh air intake to Duncan Hall has been shut down. Environmental Health and Safety is monitoring the situation and advises that, despite the odor in the building, the gas concentration is lower inside than out. We expect that the leak will be capped soon, if it hasn't already been, but I imagine that it will take some time for the gas to dissipate.