If you are considering building a shelter in your basement, we would like to talk to you. We manufacture an extensive line of equipment designed to outfit underground shelters.
From air filtration to blast protection, we have everything except the bricks and mortar.
How much protection can you get in a basement shelter?
That depends, let's look at it - there are three main aspects of shelter protection: airborne threat protection, blast protection, and radiation protection.
Airborne threat protection
Airborne threats include radioactive fallout, toxic gases, airborne biological threats, smoke, and ash. The critical component for airborne threats is a true NBC overpressure air filtration system.
This is the big question. Let's break it down. If you are building a shelter in the basement of a newly built home, you can achieve decent blast protection - 1 bar positive pressure is not a stretch. That is 14 PSI over existing atmospheric pressure. You must plan ahead and incorporate the blast resistant structure into the basement. The critical component is the roof over your protected space. See our underground blast resistant roof kit for more information.
If you are constructing a shelter in an existing basement, getting up to 14 PSI will be more difficult - but a shelter capable of withstanding a 5 PSI (720 pounds per square foot) blast will keep you alive and well when your neighbors are not so fortunate. 5 PSI can easily kill people.
You will need to consider equipping your shelter with a blast door, blast valves, and blast resistant ventilation ducts. Also worth considering is an automatic bunker ventilation system.
Radiation protection consists of managing three variables: time, distance, and mass. Of the three, time is the least controllable by shelter occupants. Distance is measured from you to to the closest fallout. If you site your shelter in the center of your basement, you get more distance, but you cannot utilize the structure of two of the basement walls like you can with a corner shelter. Mass is controllable, but heavy. The simplest way of adding mass is concrete - especially if you use that concrete for your blast resistant structure.
You can overpressure the entire basement - we have had many customers route the air outflow pipe into the adjacent basement and achieve overpressure protection for their entire basement. This allows you to store items out there and retrieve them without worrying about what you are breathing. You need to put an overpressure valve between your safe room and the basement.
You probably already have electric, water, and sewer in your basement. This saves time, trouble, and money when outfitting your shelter. With a battery backup capable NBC air filter, you will be assured of continuing your overpressure for many hours after a power outage.
You can easily incorporate a blast door into the side of your shelter. This negates having to lower supplies, people, and pets down through a blast hatch and down a ladder.
Any radioactive fallout on your roof is about 10 feet from the roof of your shelter - and with radiation - distance is your friend.
There are many other uses for your shelter: a vault for your valuables, a panic room in case of a home invasion robbery, a communications center, and a food storage area.
Family Fallout Shelter
Document number: MP-15
Date published: 1959
Published by: US Office of Civil and Defense Mobilization
Fallout Shelter - Concrete Block Shelter
- basement location
Document number: H-12-A,
Date published: April, 1980
Published by: FEMA
Fallout Shelter - modified ceiling
shelter- basement location
Document number: H-1 2-C,
Date published: May, 1980
Published by: FEMA
To get started, you should read a good primer on NBC air filtration. You can also speak with our engineer - please call 541-459-1806.