One of the instructions you may be given in an emergency is to shelter in place. This means you should stay indoors until authorities tell you it is safe or you are told to evacuate. In this scenario you would be advised to abide by the following instructions:
Select a small, interior room with no or few windows.
Close and lock all windows and exterior doors.
Turn off all fans, heating, and air conditioning systems. Close the fireplace damper.
Bring your family disaster supply kit and make sure the radio is working.
Bring your pets.
It is ideal to have a hard-wired telephone in the room you select (cellular telephone equipment may be overwhelmed or damaged during an emergency)
Use duct tape and plastic sheeting (heavier than food wrap) to seal all cracks around the door and any vents into the room.
Listen to your radio or television for further instructions or updates.
If you are in your car, close windows and turn off vents and air conditioning.