Radon safery in basement

[neazoi]

Radon safety in basement

Hi, my friend near me, has a basement and we are located in a part of our country that is NOT KNOWN if it has high soil radon concentrations. However our area is not listed in the high concentrations areas.

His basement floor is about 3 meters from top ground and has reinforced concrete walls (20cm thick) and reinforced concrete floor (about 60cm thick), both having iron bars armatures inside the concrete. The floor and the walls are joined together so the whole construction is more like a solid single piece of concrete all around the basement perimeter and floor, with no cracks in the joints to allow something to pass from the soil nearby inside the basement.

He needs to know if he is in danger because or radon, based on the above mentioned things.

I have a small cheap ($40) russian wearable dosimeter that can detect radioactivity from these old watches and I did some measurements in his basement and did not find any traces of radioactivity (at least with this meter). Wouldn't I be able to detect something even with this simple dosimeter if radon was there?

 

[betwixt]

Even if the floor didn't have concrete and went down straight to soil the level would be extremely low. To reach the surface at all the gas has to permeate from deep underground. Concrete will stop it in almost all situations and if there is any ventilation it should disperse it very quickly.

In some parts of my country there are identified Radon risks so new buildings need a plastic sheet gas barrier or forced ventilation to reduce the risks although I heve never heard of anyone being harmed in old and uprotected buildings. In most cases the 'damp course' membrane to stop ground moisture entering the concrete is sufficient to stop gas as well.

Brian.

 

[BradtheRad]

I used to live in an area where radon became a concern in 1985 (Southeast Pennsylvania). Stores started carrying inexpensive radon test kits. These were small detectors which we placed in the basement for two weeks, where they were exposed to air. Then we mailed the detector to a lab. They checked its surface for radioactive substances, then sent us the results.

A personal dosimeter is not likely to be sensitive enough. (I have some vintage civil defense dosimeters.)

Consider surveying with a scintillometer (sensitive radiation detector).

Have you seen reports that your location is near a uranium vein? Does a local business send out advertisements concerning radon safety?

According to this article, the concrete in basements is surprisingly porous, allowing radon to penetrate. Wells can also be a source of radon because it is a soluble gas.

**broken link removed**

 

[neazoi]

Even if the floor didn't have concrete and went down straight to soil the level would be extremely low. To reach the surface at all the gas has to permeate from deep underground. Concrete will stop it in almost all situations and if there is any ventilation it should disperse it very quickly.

In some parts of my country there are identified Radon risks so new buildings need a plastic sheet gas barrier or forced ventilation to reduce the risks although I heve never heard of anyone being harmed in old and uprotected buildings. In most cases the 'damp course' membrane to stop ground moisture entering the concrete is sufficient to stop gas as well.

Brian.

I do not think there is anyone in my area (Rio city in Greece) that has identified such risk. In US and UK, people may be more suspected to the subject, but the general public here does not. I see some reports from Greek universities, for high levels, but these are in the nothern Greece far away from me. However the map I attach shows some levels and no information for nothern Greece. I leave there the arrow line points.

And no as fas as I am aware of, There is not such uranium industry in Greece, but that doesn't mean there is no uranium.

I was not aware of the radon test kits, I will buy one. I see there are two of them the long term one and the short term one (a few days). I think I am going to close the basement doors for a few days and put the kit inside.
However my basement is new (about 5 years old) and there are no cracks, at least not visible.


I forgot to mention that there are no sinks or holes drilled in any of the basement walls. The only hole to the concrete is a small nail where it is used as a hanger. This penetrates the 20cm wall only about a few cm (2-3). I see no signs of color transformation on the wall at this place, which would indicate water comming in from any pores in the concrete.
All the cabling is inside plastic channels that just touch the wall. The only hole the wall has, is above ground level, by the window, where the cabling goes out to the rest of his house.
It is really a solid box out of concrete.
Do you think it will block radon gas, or this gas can penetrate through 20cm concrete??

Now BradtheRad mentioned the site about the porosity of the concrete. But how about a 60cm width of concrete on the floor and 20cm on the walls?
What kind of gas is it that can penetrate so much concrete? Doesn't it seem to you that the site tries to sell something? If it was so d*mn dangerous, wouldn't the sinks in the rest of the house pose a problem, as they communicate with the sewer deep underground (through the siphon though)?

My neighbour lives in a basement about 100 meters from me, for more than 20 years now and he is healthy. Unless this gas exist just below my house and not his...?

Based on the parameters explained in my situation, do you think keeping the narrow basement windows open at all times, will be sufficient to solve the problem (if it exists at all)? I am there quite a few hours a day...

 

[betwixt]

The map can be misleading because the coloring makes it look like white is lowest risk, it actually means there is no information on that location. If information had been available it would all be at least yellow (0 < 100 Bq/M3). It is possible there are small 'hot spots', especially in a country like yours where there is seismic and volcanic activity but the chances are small and even a small amount of ventelation should keep the dosage well below danger levels.

All houses built in the last 40 years or so in the UK have a membrane in the concrete to keep ground water from being absorbed into the foundations and the same material is classed as a radon membrane. I'm not sure if the same regulations apply in your area but if you have a plastic layer under the concrete you should have no worries anyway.

I wonder why the map shows higher levels inside the Czech Republic border than all the surrounding areas - it is either bad luck for people there or some difference in the way they collect data in that country.

Brian.

 

[c_mitra]

Radon is a gas and has a short half-life and is an alpha emitter. Inhaled radon is very dangerous. Radon comes from mining activities and can accumulated in enclosed spaces. If your basement has a decent ventilation, you need not worry.

Most common dosimeters detect beta and gamma because alpha is stopped with a Al-foil or a thick cardboard.

 

[neazoi]

Radon is a gas and has a short half-life and is an alpha emitter. Inhaled radon is very dangerous. Radon comes from mining activities and can accumulated in enclosed spaces. If your basement has a decent ventilation, you need not worry.

Most common dosimeters detect beta and gamma because alpha is stopped with a Al-foil or a thick cardboard.

Searching around, I found an area in the house, other than the "concrete sealed" basement, where soil is directly exposed to within the house atmosphere!
This area is a total of about 1-2 square meters of soil (in a straight line) and it forms a gap between the main building and an auxilary building. This is not in the basement, but in ground level. The bad thing is that the two buildings seem to be one, but in fact are two, that set apart 10-15cm by this line of soil. This had been done so that earthquakes affect different each of the buildings.

The problem is that this line of soil directly communicates with the internal of the house. If cracks in the walls said to be a problem, this is a biggest ***** you can imagine. The roof of this line of soil is open at about 2-3cm all the way and there is a small opening (10cm in diameter) at one end for passive ventilation purposes.
Because of these openings we are loosing heat in winter, if you place your hand near the opening you can feel the cold air comming inside the house. Of course some days there is no wind and no air flow is happening

Do you think that this can allow significant ammount of radon to come in the house. I have not yet measured for radon but I will do so with one of these **broken link removed** However they have to be placed in a air flow free place so that radon is allowed to be build up, whereas my place is not always air flow free.

 

[c_mitra]

Do you think that this can allow significant ammount of radon to come in the house.

Radon is a decay product of Uranium and other series of radioactive elements. These elements have long half lives and they are usually trapped minerals (rock). When the rocks are broken (mining activities) the trapped radon is released (it can happen even with coal mining) and comes out in the air. Normal soil that is exposed to the air has already lost the trapped radon over the ages and is not a threat.

In fact, concrete or cement can be a bigger source of radon than soil. Stone houses (exposed walls) can be also a source.

 

[neazoi]

Radon is a decay product of Uranium and other series of radioactive elements. These elements have long half lives and they are usually trapped minerals (rock). When the rocks are broken (mining activities) the trapped radon is released (it can happen even with coal mining) and comes out in the air. Normal soil that is exposed to the air has already lost the trapped radon over the ages and is not a threat.

In fact, concrete or cement can be a bigger source of radon than soil. Stone houses (exposed walls) can be also a source.

I am not expert but I have the feeling that if the problem was too serious about concrete and other house building materials like bricks, everyone would die from lung cancer. I have lived in UK for quite a few years and I was surprized that the house windows did not open all the way. This same thing happens ont he windows in the basement, but in the rest of the house, windows open all the way.

Do you believe, keeping the windows in a basement open at almost all times can minimize any threat?
One of the basement rooms has no windows, but I keep the door open, while the windows in the other rooms are open. Would that be ok?

According to this map https://eeae.gr/en/radon-map from an official Greek Source, the measurements that have been done in my area show a level of 56.81Bq/m^3.
Do you think that radon can be built up in significant ammounts in the basement if I keep these windows open, so that there is a continuous flow of air, even a very slight one?

Or shall I install a fan to create an artificial flow of air?

My biggest question is that, will radon be build in significant amounts during the night, where I have the windows closed, untill I open them again in the morning?
In other words, do I need to keep the windows at all times open or just 1-2 times a day it is ok?

 

[betwixt]

The risk is extremely small even with the windows closed all the time. ~57Bq/m^3 is classed as very low, consider that measuring almost anywhere in the World will give some small 'background' reading. The build up to dangerous levels could take weeks in an unventelated but pervious room. Circulating the air occasionally by opening windows or doors should keep the Radon down to insignificant amounts. If there were identified high risks, I'm sure the local authorities would advise on ways to insulate existing buildings and insist on barriers being fitted to all new constructions.

Brian.

 

[neazoi]

The risk is extremely small even with the windows closed all the time. ~57Bq/m^3 is classed as very low, consider that measuring almost anywhere in the World will give some small 'background' reading. The build up to dangerous levels could take weeks in an unventelated but pervious room. Circulating the air occasionally by opening windows or doors should keep the Radon down to insignificant amounts. If there were identified high risks, I'm sure the local authorities would advise on ways to insulate existing buildings and insist on barriers being fitted to all new constructions.

Brian.

I have to hope so, although I generally have a disbelief about the local authorities here, as in a country that is in a bad economical situation, who would care about these "insignificant" things...?
It is only the last years that this thing arised here, whereas in countries like yours people and government cope with this much more years.
However, to be honest, I was very surprized and glad I contacted the Greek National Newclear Agency eeae.gr and they responded next day, to send 6-months tests to conduct for free. Maybe some things work better than I thought here as well, time will show...

It is funny, grandfathers kept saying to me, to open up the windows at least once a day in the house. They did not know anything about Radon, but they were right, like so many other things

 

[c_mitra]

The wikipedia has some relevant information: https://en.wikipedia.org/wiki/Radon

Damage from radioactive decay (cancer from radon) is a first order process and is probabilistic in nature. Of course, higher concentration of Radon naturally means greater damage. Remember that Radon comes from the naturally present uranium and thorium in all rocks. These two parent elements have long half lives and they produce radon at a very slow but steady rate. Because it is a gas, it is of concern.

 

[neazoi]

The wikipedia has some relevant information: https://en.wikipedia.org/wiki/Radon

Damage from radioactive decay (cancer from radon) is a first order process and is probabilistic in nature. Of course, higher concentration of Radon naturally means greater damage. Remember that Radon comes from the naturally present uranium and thorium in all rocks. These two parent elements have long half lives and they produce radon at a very slow but steady rate. Because it is a gas, it is of concern.

From all the things that I read and mentioned in this thread, what I understand is that tiny amounts are not going to hurt. It is when radon is allowed to be gradually built in large amounts, that is bad.
This can happen in places with no ventilation and these places are usually basements, used for storage purposes and it can take days, or even weeks to open the windows on them.
And of course the area one lives plays a role in the amounts or radon from the soil.
A basement with the windows open for a few hours a day, will not brodably kill you.

Am I getting the general idea right?

 

[c_mitra]

Am I getting the general idea right?

Not quite.

A single atom of radon that enters the lungs and decays while inside can cause considerable damage.

The radionuclide is an alpha emitter; alpha particles have lots of energy but very little penetration power.

In other words, if the concentration is low, chances that one single atom will enter the lungs can decay while inside the lungs and cause severe damage is *LOW*

This "low" is to be understood in a statistical sense; it is just like a car accident. If all of us are careful drivers the accident rate will come down. Unfortunately, the decay products of radon are also radioactive and they can deposit on the tissues causing more damage.

Mostly, the natural concentration of radon is about the background level and because it has a short half life, it cannot build up to a high level. The half life is of the order of days.

Because the numbers are so small, fluctuations are large. In other words, most people who live in the basements do not die of lung cancer (but they are subject to).

 

[neazoi]

Not quite.

A single atom of radon that enters the lungs and decays while inside can cause considerable damage.

The radionuclide is an alpha emitter; alpha particles have lots of energy but very little penetration power.

In other words, if the concentration is low, chances that one single atom will enter the lungs can decay while inside the lungs and cause severe damage is *LOW*

This "low" is to be understood in a statistical sense; it is just like a car accident. If all of us are careful drivers the accident rate will come down. Unfortunately, the decay products of radon are also radioactive and they can deposit on the tissues causing more damage.

Mostly, the natural concentration of radon is about the background level and because it has a short half life, it cannot build up to a high level. The half life is of the order of days.

Because the numbers are so small, fluctuations are large. In other words, most people who live in the basements do not die of lung cancer (but they are subject to).

All right I got it.
A major problem is houses with basements, like mine. Even if one does not live in the basement, won't the radon come up to the upper floors of the house?
I have no idea if radon is heavier or lighter than air.
Of course we can't catch up single atoms, so in practical terms, opening the basement windows for quite a few hours a day, would generally suffice or not? What do you think?

 

[betwixt]

There are about 10.9 Million people in Greece and (excluding migrant crisis) the number is increasing so it can't be that dangerous!

It is about 8 times heavier than normal atmospheric Nitrogen/Oxygen mix so it would tend to collect in lower areas but it has a half-life of less than 4 days so it's radiactive toxicity decays quite quickly and don't forget it could already be quite 'old' since being Radium. Neverthelsss, it is the major contributor to everyone's (World wide) radiation dosage. Most danger comes from inhaling contaminated dust rather than the gas itself and some of it's decay products can bind to small dust particles. The danger is still very small though and there is more chance of you being poisoned by drinking radon contaminated ground water than from the gas itself.

Brian.