Whether you are at home, work or elsewhere, there may be situations when it's simply best to stay where you are and avoid any uncertainty outside.
There may be circumstances when staying put and creating a barrier between yourself and potentially contaminated air outside, a process known as "sealing the room," is a matter of survival.
Use common sense and available information to assess the situation and determine if there is immediate danger. If you see large amounts of debris in the air, or if local authorities say the air is badly contaminated, you may want to take this kind of action.
The process used to seal the room is considered a temporary protective measure to create a barrier between you and potentially contaminated air outside. It is a type of sheltering in place that requires preplanning.
- Bring your family and pets inside.
- Lock doors, close windows, air vents and fireplace dampers.
- Turn off fans, air conditioning and forced air heating systems.
- Take your emergency supply kit unless you have reason to believe it has been contaminated.
- Go into an interior room with few windows, if possible.
- Seal all windows, doors and air vents with 2-4 mil. thick plastic sheeting and duct tape. Consider measuring and cutting the sheeting in advance to save time.
- Cut the plastic sheeting several inches wider than the openings and label each sheet.
- Duct tape plastic at corners first and then tape down all edges.
- Be prepared to improvise and use what you have on hand to seal gaps so that you create a barrier between yourself and any contamination.
- Local authorities may not immediately be able to provide information on what is happening and what you should do. However, you should watch TV, listen to the radio or check the Internet often for official news and instructions as they become available.
Shelter Safety for Sealed Rooms
Ten square feet of floor space per person will provide sufficient air to prevent carbon dioxide build-up for up to five hours, assuming a normal breathing rate while resting.
However, local officials are unlikely to recommend the public shelter in a sealed room for more than 2-3 hours because the effectiveness of such sheltering diminishes with time as the contaminated outside air gradually seeps into the shelter. At this point, evacuation from the area is the better protective action to take.
Also you should ventilate the shelter when the emergency has passed to avoid breathing contaminated air still inside the shelter.
Source: Ready.gov - Federal Emergency Management Agency (FEMA)- Last updated: 02/12/2013 - 09:53 AM