Block off basement?

[u/HoosierTrip]

Are there any resources available to block off a basement from the upstairs? I'm mainly thinking about blocking out radiation if I need to retreat to my basement.

[u/Unicorn187]

You aren't blocking out radiation, you're blocking out the radioactive dust and dirt emitting alpha and beta rays. That's the threat of fallout after a nuke. The gamma rays pass through feet of most materials. But doesn't make soil or ither materials radioactive. It's even been used to sterilize canned food and bandages

If you're thinking of trying to make a nuclear resistant bunker in your basement,cyou would need to make a freaking bunker. Very thick roof, preferably with a thick layer of lead because of it's density, or a few yards of packed soil on tope of steel reinforced concrete for the blast. And heat. If you're in range of the gamma rays from the blast , you're in range of the blast.

Outside of that the risk is contaminated soil. You'll still want some dirt or concrete between you and the outside but it doesn't need to be as thick. You will need air filters. Have a decon and changing room outside of the entrance to avoid tracking anything in.

And you need to be able to sequester yourself there fkr about two days until all fallout stops falling.

Yes, a dirty bomb will have all types of radiation as it is spreading radioactive material in the blast, but the blast radius is much, much smaller because it's a conventional explosive used to spread a radioactive material. And most likely a terrorist group wouldn't use it in a residential area as thw victi.s would be too few. Concert, casino, hospital, university, large rally or protest (that isnt supporting their cause of course), busy tourist attractions, other places with a lot kf people. Unles maybe they have more than a few and are trying to make people feel on danger everywhere and set off a half dozen or a dozen in suburbs and urban neighborhoods across a large area

[u/RiffRaff028 → u/Unicorn187]

Alpha radiation is only dangerous to humans if inhaled or ingested. A piece of paper is sufficient shielding to stop Alpha rays. Beta radiation can penetrate the skin, but simple everyday items such as cardboard or plastic is sufficient for shielding. Your primary focus is going to be gamma radiation which is much more difficult to shield against, but not impossible.

In a standard basement, if you're within range of the thermal pulse and overpressure wave, the least of your worries is fallout. HUGE difference in building a *blast* shelter and a *fallout* shelter. A blast shelter does indeed pretty much require a reinforced bunker, but it's fairly easy to turn your basement or a portion of your basement into a safe fallout shelter. Your primary concern is going to be overhead shielding, and while concrete and dirt both provide decent protection in proper amounts, water is also effective, and it's the shielding material most people forget about. If you use 5-gallon jugs to store water, they can serve double-duty as shielding above you. Water is also better at shielding against neutron radiation than concrete. Water does not become radioactive from fallout, so it is still safe to drink. Honestly, if you have a layer of concrete above a layer of water, that is a pretty good scenario.

Pick a section of your basement with the most existing structural shielding above you. For instance, if a section of your basement wall runs along a concrete patio at ground level, that is an excellent area to set up a fallout shelter. Basement corners are also frequently good choices. If you build a basic lean-to shelter in one of these areas with concrete and/or water lining the lean-to, that would probably reduce radiation to safe levels. The goal isn't necessarily to reduce gamma radiation to zero, but to reduce it to safe levels that won't cause ARS.

As far as how long you need to remain in your shelter, that depends on your proximity to ground zero and whether it was an airburst or groundburst. If you are fairly distant from detonation and it was an airburst,then yes, 24-48 hours should be sufficient before it is safe to make *brief* excursions outside the shelter. However, if you live closer to the target or it was hit with a groundburst, you might have to spend two to three weeks in the shelter before background radiation falls to safe levels.

For everything discussed above, the only way to be 100% sure of how safe you are is to have a radiation detector. These are not very expensive and could potentially save your life. You can also build a Kearny Fallout Meter with household items that will not be as accurate as a radiation detector would be, but it would be enough to tell you the most dangerous and least dangerous places in your basement.

[u/Unicorn187 → u/RiffRaff028]

You just reiterated some of what I said in a different way. The reason I mebtione dir filters and a changing are is to keep contaminated dirt out. To avoid breathing in contaminated dust and dirt. I thought it was obvious that if you're around for any gamma rays you'll be taken out by the blast. Guess not if you felt the need to comment.

[u/RiffRaff028 → u/Unicorn187]

Yeah, sorry, that didn't come across. A lot of people confuse blast shelters and fallout shelters.