Shelter in Place
Some types of chemical accidents, chemical attacks, or weather emergencies may make going outdoors dangerous. Leaving the area might take too long or put you in harm’s way. In such a case it may be safer for you to stay indoors than to go outside.
“Shelter in place” means to make a shelter out of the place you are in. It is a way for you to make the building as safe as possible to protect yourself until help arrives. You should not try to shelter in a vehicle unless you have no other choice. Vehicles are not airtight enough to give you adequate protection from chemicals. In fact studies have shown that vehicles pull much more air into them while operating than air that would enter a poorly sealed building.
If you hear or read the announcement to “shelter in place”, you should either remain in the building you are in or, if you are outside, proceed to a building closeby. Building occupants should then make their best effort to close windows, and shut down any exhaust devices in their rooms. This would include turning off air conditioners / heating units, bathroom fans, and any other devices that draw air into the building.
Shelter in place announcements are different than “take shelter” messages that may be associated with tornado warnings. Move away from windows to a small room or in your room contains a window, move to the hallway. Additional planning and action references for tornado warnings include:
http://www.nhc.noaa.gov/HAW2/english/tornadoes.shtml#actions
http://www.sarpy.com/ema/tornadof.htm