1999 Buick LeSabre Owner's Manual - Page 192

yellowblue D Tie a red cloth to your vehicle to alert police that you've been stopped by the snow. D Put on extra clothing or wrap a blanket around you. CAUTION: Snow can trap exhaust gases under your vehicle. This can cause deadly CO (carbon monoxide) gas to get inside. CO could overcome you and kill you. You can't see it or smell it, so you might not know it is in your vehicle. Clear away snow from around the base of your vehicle, especially any that is blocking your exhaust pipe. And check around again from time to time to be sure snow doesn't collect there. Open a window just a little on the side of the vehicle that's away from the wind. This will help keep CO out. If you have no blankets or extra clothing, make body insulators from newspapers, burlap bags, rags, floor mats -- anything you can wrap around yourself or tuck under your clothing to keep warm. You can run the engine to keep warm, but be careful. 4-28