This is easy to achieve. Just start up the Escape map The Barracks
on beginner (Escape > Custom > Host Private > Barracks). As soon as you leave the starting area look for a control panel. It should be to the right and will have a green light on it with a switch. Hit that switch (
) and it will activate a "venom fan".
This is what your looking for:
Video for the visual need:
Sorry, this Game Clip has been removed