Simple homemade filter for radioactivity

I read online somewhere how to use a 5 gallon bucket to filter water in case of nuclear event to filter out radioactivity.  Poke a bunch of small holes in bottom of 5 gallon bucket.  Put 2 inches of gravel or small pebbles in bottom.  Put down a handtowel and then add 6” of clay dirt.  Towel is to stop gravel and dirt from mixing.  Pack it down really good on top.  Then add another towel.  Put inch of rocks on top of this second towel to hold towel down.  Pour water over top to filter fallout.  Still need to boil water or use Berkey to filter before drinking.

We do not have clay soil in our area.  Can I purchase fire clay from Pottery Supply instead??

I would not rely on a homemade filter for radioactivity.

That filter would work for filtering rainwater or well water under normal circumstances.

May be this article will help explain:

Reverse osmosis (RO) is supported by the EPA as a “best available technology” for various radioactive elements, including alpha and beta particles, uranium, radium and photon emitters. According to the EPA, it can remove up to 99% of these contaminants, while RO units can be automated and compact.

https://www.water-technology.net/features/feature121661/

Thank you for the input.  I have RO installed in my kitchen but this is more for a grid down situation after a nuclear event and I would not have running water.  I would use my RO water first that I have stored but would run out probaby after a week or so...

The article you kindly attached says:  
"Iodine-131, however, is usually found in water as a dissolved gas, rendering reverse osmosis (which cannot capture gases) an ineffective treatment mode. It can be removed using a combination of relatively simple technologies, though, and personal radiation water filters are available, utilising filtration methods and medias frequently used in the nuclear power industry. The EPA recommends the general public adopt a process combining activated carbon, reverse osmosis and ion exchange – effectively covering all bases."

Not sure if there is a gizmo that utilizes all three processes it mentioned...

Beth Mouse wrote: ".......The EPA recommends the general public adopt a process combining activated carbon, reverse osmosis and ion exchange – effectively covering all bases."

Not sure if there is a gizmo that utilizes all three processes it mentioned...

Although designed (and typically priced!) for laboratory settings, if you want to get pretty pure with your water, you may want to search out the water purification systems at https://www.emdmillipore.com/ . These likely would have the goods for removing to acceptable levels whatever you wish from your water.  One example from one system shown below.  Most home under-the-sink reverse osmosis filters would provide the 'input water feed' for a Millipore water purifier and the whole system typically mounts on a wall (3 X 3 ft square space) but could be mounted under a roomy sink.  Good luck!....

Hi, regarding the removal of radioactivity from water, is it really necessary to have such a complicated system? Wouldn't an activated charcoal filter be sufficient in itself? Also, our water supply comes from an underground spring, gravity-fed through underground pipes. Will the soil act as enough of a filter to protect the water quality?

Lots of interesting points made on this thread.  But going back to the original post, I can’t comment much about fire clay, but for my purposes, I would substitute activated charcoal or Biochar as an absorption medium.

This might help filter out some radioactive particulate material, but certainly won’t catch everything.  Regarding the Iodine 131 poisoning, the best solution is a simple preventative measure—have on hand and take an iodine tablet at the onset of any such event.  This will help prevent the absorption and uptake of the radioactive Iodine-131.  And to put your mind at ease, that Iodine-131, while fairly radioactive has a short half-life and will decay quickly.

As for other particulates caught in the activated charcoal, I would recommend emptying and disposal of the used activated charcoal on a semi-frequent basis.  For home purposes, I would think about building a little cement block “compost pile”, preferably with a cement bottom and a roof to keep out rain and snow.  I would fill those cinder blocks with more cement, add water and let sit (rebar might be a good idea).  Keep this as far from your house as practical.

I know this all sounds like a lot, but the mass of all that cement will do a great job at absorbing X-rays and at least some Gamma rays.  The water in the cement will slow any neutrons released and generally make that radiation less dangerous.  And if you are really serious about this, this would be a relatively low-cost form of storage.  I am thinking of a 4x4’ bin, so nothing huge.  Also, keeping the bin far away will minimize any radiation you will absorb.

On the good news, the most dangerous radioactive elements are the short half-life isotopes.  As the half-life’s get longer, the intensity of radiation goes down.  Hopefully this bin never gets filled (or used!) and it’s contents can simply sit in long-term time-out.

I am not trying to spend all your money, but if you are concerned about radioactive particles, they will build up in the filter and the filter’s contents will need disposal occasionally and this is a way to not simply dump more radiation back onto your property.

Eric

Hi Gerda,

Welcome to Permies.