Last night (after reports were submitted) an emergency evacuation drill was conducted. Paul Graham (who was already at MDRS to carry out observatory training) and I surprised the crew with an intricately simulated LP-leak. The crew successfully evacuated the hab quickly and safely, and got as far as shutting off the LP tank before we terminated the drill. I have checked most of the smoke, carbon monoxide & LP detectors, and will complete the Bi-Monthly Safety Inspection tonight.