Sheltering-in-Place

A safe room, also known as a shelter-in-place, can be a permanent or an improvised shelter, often erected within a house or apartment, which protects its occupants from the toxic effects of chemical, biological or radiological weapons. It is not intended to protect against explosive blasts or natural disasters such as tornadoes, hurricanes, etc.

A permanent safe room is usually equipped with a High Efficiency Particulate Air (HEPA) filtration device. HEPA filters were developed by the U.S. government to protect against radioactive airborne particles. They filter out 99.97% of particles 0.3 microns and smaller, including dust, mold spores, dust mites, pet dander and many biological agents. HEPA filters are not effective against most chemical agents.

An improvised safe room has no air exchange with the outside.
Since a safe room’s purpose is to create a completely airtight protective seal around its occupants, it must be designed with enough air space to allow them enough oxygen for a long enough period of time (several hours minimum) to protect them from the initial effects an aerosol chemical attack.

Safe Room Design and Construction

Choose a site for the safe room on an upper floor (not the basement) with few or no windows. The fewer outside walls, the better. A room with an adjoining bathroom is ideal. If an inside room without windows is not available, a master bedroom makes for a good site since it will usually include full bathroom facilities, a TV, a hard-wired phone (important since wireless networks may be overwhelmed in an emergency) and is comfortable.

WARNING! Basement rooms, while relatively effective as protection sites against nuclear attack, should not be chosen because most chemicals, gases and dust are heavier than air and will settle in low places.

The room should have a minimum of one-square yard of floor space per person. In planning for a safe room — In a time of crisis you may have unexpected visitors who will take up space and air resources. It’s best to make allowances for two to four extra people.