Radon - soley pragmatic investigation-based information

What is Radon?

What it is

Radon is an element; one of the "inert gases". It is radioactive.

Where it is

Radon in Cornwall is understood to come from Uranium in the igneous-intruded granites which give the well-known copper and tin ores mined in Cornwall.
Uranium has been mined in Cornwall, from lodes which are notably rich in Uranium.

Not all tin ores give Radon. The currently-operating tin mine in Tasmania is reputed to have zero Radon. For the presumed reason that there is no Uranium in that granitic intruded mineral.

What is the issue

Radon is radioactive.
As Radon is an inert gas, in itself it cannot be a concern because it cannot interact with the body. Due to having no chemical interactions. It cannot concentrate or be retained. What is breathed in is immediately breathed out.

The concern is that the radioactive decompositions give "daughter products" which could be harmful.


This article solely looks at information provided by practical investigation and pragmatic evaluation.
An alternative description is - only information with demonstrable proof is presented here.

Axiomatic official assertions can have financial influences, like favouring those creating long-term secure jobs. Diluting certainty of quality and/or validity.
Inferences of partiality of arguments in favour of Radon being harmful:

Radiation levels and scale conversions

The average background radiation in the UK is given as about 18 counts per minute with a Geiger counter. Which is 0.1 micro-Sievert per hour.

According to Nick's Geiger Counter Page [external link], multiply Geiger counter counts-per-minute by 0.0057 to get radiation exposure in micro-Sieverts per hour.

The legal maximum for radiation shine beyond the exclusion perimeter of site where industrial radiography is being performed is 7.5micro-Sieverts per hour. Which would be about 1300 counts per minute on a Geiger counter.


United States Bureau of Mines


Published in 1960, Radiation Protection in Uranium Mines is a film by the United States Bureau of Mines.

Seemingly better preserved with (close to) original colour is this version of the same film (???) on "YouTube" channel A/V Geeks 16mm Films, titled "Protection Against Radiation In Uranium Mine", with run-length of 26:07 (minutes:seconds).


Being a study of Uranium mines, the levels of Radon these miners will have been in are certainly high. Significantly higher than in Cornish tin mines? Even with systematic reduction of Radon exposure by mine ventilation there must be durations of much higher exposure prior to precautions being introduced or in regions where the ventilation has not reached.


The significant observation is that uranium miners who smoke have a much higher incidence of cancers.
Given what we now know: this study is finding the effect of cigarette-smoking. Before that cause was identified.
There seems to have been no significant increase in cancers and other ailments for uranium miners who did not smoke.

Given the size of the sample and the amount of uranium mining happening in the USA then, with the nuclear weapons program and securing indigenous uranium sources : this body of evidence rejects the hypothesis that radon, even in high levels met in uranium mining, causes ailments even when incidence of cancers is closely scrutinised.

"Radioactive Drew" from the USA


Radioactive Drew is the YouTube channel of a guy in the United States. He seems to be a practical sort, who makes videos centred around radiation measurements. In "interesting" cases - what is the story of how this came to be; what are its characteristics; etc.

The video of interest here is titled
"Radon, A Radioactive Gas, Healthy?...or Harmful."

A link is not given because YouTube changes URL's of videos at intervals. The link to the channel should stay current and this particular video can be identified on the channel.
The still image in the "thumbnail" linking to the video shows a man wearing a dust-mask with pink filter-enclosures next to a yellow sign warning of radioactivity.


This guy I take to be called Drew is your American big practical outgoing open enthusiastic personality. The notably good aspect of the USA.

He goes to two very different locations which were Uranium mines and have Radon.

Health Spa mine

This is an ex uranium mine now purposed as a health spa.
That is correct : "The Radon Health Mine" and others like it are visited by those who hold that radon in mines can bring relief from ailments like arthritis, rheumatism, migraines and asthma.
As a scientist I struggle to visualise a physical means by which benefits to occur : however given how unpleasant and debilitating are these ailments, if anyone perceives they get relief I welcome that.
The "Free Enterprise" repurposed mine as a health facility has 1720pCi/L (1:35 / 24:12) of radioactivity - presented as all being caused by Radon. This is 320X the level of 200 Bq/m3 (5.4 pCi/L) above which it is recommended that mitigation methods be applied to reduce radon levels if found in a building. But still very very low.
The radiation level recorded in the mine by a Geiger counter is around 13,000 counts per minute (74micro-Sieverts per hour), which is 740X the average UK background radiation level.

"Active" Utah mine

This other location is a long-closed Uranium mine in the Utah which seems recognised for abundant levels of radiation.
He records around 24thousand counts per minute on his Geiger counter inside the mine portal - around 137micro-Sieverts per hour.
Which is 18X the permitted radiation shine at the perimeter of a site where industrial radiagraphy is being performed, and over 1300X the UK average background radiation level.

A piece of ore gives 90,000 counts per minute (about 513micro-Sieverts per hour) - 68X the site perimeter maximum radiation shine and 5000X the UK average background radiation level.

Wheal Providence mine at Carbis Bay, Cornwall, has lodes which it is shown give 37 micro-Sieverts per hour - so the somewhat ominous background music [link to YouTube channel - see "Carbis Bay Radioactivity"] is perhaps only so-so proportionate. That is though 370X average UK background radiation level and around 5X the permitted maximum radiation level at the exclusion perimeter where industrial radiography is being done (see 5:58 / 13:11 - he cites 308X background radiation level)

Drew demonstrates that emerging from the mine he is now notably radioactive, at around 12,000 counts per minute.
His dust-mask filters are showing 65,000 counts per minute (about 370 micro-Sieverts per hour).

Changing clothes, the T-shirt worn inside the mine is showing 29,000 counts per minute.
The significant demonstration is that 24hours later, that radiation level has dropped to 85 counts per minute.


The value here are the basic things implied above but not expressly mentioned then.

The most practically significant is that where Radon is present a Geiger counter reveals that.
Seemingly no special instrument is needed. Drew does have a dedicated "Radon meter", and it is seen that the Geiger counter and "Radon meter" concur on whether there is much or little radioactivity.

The solid "daughter-products" of Radon decay do seem to "contaminate" persons and objects. These must be the solid because the radiactivity persists having left the mine. Radon as an inert gas could not cling and would be dissipated by air movement outside the mine.

The best inference that there are solid daughter-products of Radon disintegration is the radioactivity of the dust-mask filters (?). Surely these could not accumulate Radon - especially as the wearer is breathing through the filters, so making any selective concentration of this gas impossible (?).
Whereas the filters would be expected to accumulate solid particles in the air breathed - if for no other reason that the large surface area the filters present.

Taking it that Radon radioactivity particulate daughter-products is proven : that the radioactivity of "contaminated" items is almost fully half-lived away in 24 hours is also very significant.

The daughter-products particle size is expected to be small, coming from the disintegration of individual atoms of Radon. This seems to be confirmed in information found on web-searching.
Small particles would readily be inhaled deep into the lungs.
The daughter products are Alpha radiation emitters. While Alpha radiation cannot penetrate a sheet of paper, inhaled as a particle and settling on the lining of the lung the living cells nearest the daughter-product particle would presumably get highly ionised by absorbing in-entirety the Alpha radiation energy.
That said

No decisive proof is achieved here of whether Radon exposure is harmful or not.

That the presence of Radon is shown to be revealed by a "regular" Geiger counter is a valuable demonstration.

Ask a retired doctor

The question asked to a retired medical doctor who I approached for help was - is there any demonstrated basis for concern that Radon could cause ailments including cancers?
If so, citation of these sources was sought.

While not an irrefutable proof, it was not possible in a short time for this experienced doctor to identify well-proven demonstrations of Radon causing ailments including cancers.

Epidemiology from places with high natural radioactivity

It is widely known that the Talesh Mahalleh district of Ramsar in Iran has the highest natural radioactivity of any inhabited area in the World [Wikipedia link] .
Radiation levels measure at figures like 140 micro-Sieverts per hour inside dwellings - 1400X UK average background and 18X the legal limit for radiation shining beyond the perimeter of sites from industrial radiography being performed.
This radioactivity has at least some component of Radon presence and its decay.
So one might ask - is there epidemiological evidence of a higher incidence of ailments - including cancers - in that area?
There is epidemiological evidence over centuries, and no health detriments are revealed.
Which seems unexpected, given other claims regarding radiation and Radon.

I suggest this is weak evidence against the presence of Radon in any natural concentrations being more than marginally detrimental to health.
It seems strong evidence that the presence of natural concentrations of Radon is not strongly detrimental to health.


I am not equipped to state conclusions.

The United States Bureau of Mines study finds that miners in Uranium mines, some with very high radioactivity and Radon levels, have not much elevated incidence of ailments including cancer.
This one study cannot be compelling absolute evidence.

The practical demonstration that "ordinary" Geiger counters reveal the presence of Radon is very valuable.
This means if the radiation level indicated on a Geiger counter is low, the concentration of Radon and its daughter-products of decay must be low.

(R. Smith, 23Feb2024 to 24Feb2024)