It was Jimmy Carter days and the OPEC Oil crisis. Prior to 1973... electricity and heating oil was cheap, there were many single pane windows that didn't seal completely. So the default condition was houses as originally built, cooler temps in Winter and more natural ventilation in houses with corresponding higher energy costs.
In 1973 fears that heating in Winter would get more expensive, saw an increase in home renovation. IR viewers were employed for the first time and IR images showed windows and attic vents as glowing with heat (as they had all along) and it looked like money escaping. Rubber seals on doors and windows. Double pane windows.
This trapped the radon in basements (and for some rising out of the basement onto the first floor) to be breathed by humans and gain higher concentrations for the first time in US history. Homes were hermetically sealed.
Since smokers bore the penance of sin... the rise of the '2nd leading cause' went unrecognized for years.
Radon is measurable, my CO2 detector also mesures radon. There is none in my well-insulated house.
Now in a basement in Brittany things would be different, but for most houses in most places, radon is negligible.
There also isn't a notable difference in cancers between radon-rich granitic places like Brittany and the rest of France. I feel like at least in France, the potential dangers of radon are well known.
It always struck me as odd that radon in basements seems to be a big thing in North America, but is relatively un(der)reported of elsewhere. Is this just a matter of the US being too cautious? Is there perhaps more radon in basements over there? Or does the rest of the world not give a shit for some reason?
It depends on which type of ground you build on. The Nordics are mostly granite and have a relatively big problem with radon gas, or at least enough that people in general care about it. Continental Europe is dominated by limestome which hasn't got the same problem.
I expect that Americans spend more time in their basements than people in most other countries (other than Canada). The kind of furnished basement that teenagers hang out in from That 70's Show isn't common elsewhere.
Wrong and wrong. Not all parts of the world have issues with radon, depends on what’s in the ground underneath. Absolutely those countries do care and people are generally aware of it especially in the building process.
I don't know about "rest of the world", but I think in western Europe it is simply just another thing that gets inspected uneventfully, like making sure there is a fuse box.
When I finally got to buy a home, we chose one built in the fourties because we really didn't like the feel of newer homes. Love it, but yeah, plenty drafty..erm I mean, fresh air. I do have to worry about lead paint though, which I found out with a cabinet remake.
This depends very much on the soil composition. Some areas might have almost no radon, whereas others do. Here's a high-level view of radon probably by county (WA state), but you can find local maps that show it at the neighborhood level. We looked at the maps when buying our house, had it tested, and radon levels were high so we installed a mitigation system in our garage (which is the bottom level of our house).
This is also making things worse for houses with water damage and mold issues for the same reasons. The concentrations can rise rapidly as there is no dilution effect from leaks or open windows (most houses are always closed up in today's lifestyle).
In 1973 fears that heating in Winter would get more expensive, saw an increase in home renovation. IR viewers were employed for the first time and IR images showed windows and attic vents as glowing with heat (as they had all along) and it looked like money escaping. Rubber seals on doors and windows. Double pane windows.
This trapped the radon in basements (and for some rising out of the basement onto the first floor) to be breathed by humans and gain higher concentrations for the first time in US history. Homes were hermetically sealed.
Since smokers bore the penance of sin... the rise of the '2nd leading cause' went unrecognized for years.