Doesn’t granite produce radiation? Every so often a customer asks this question. It may not be one of our most frequently asked questions, but any question deserves a decent, honest answer. And occasionally an article in a newspaper dealing with Radon gas in the home mentions granite worktops, and we see a wave of people worrying about whether their worktops could harm their health. On top of that, there are a few websites in, oddly enough, the United States of America, which really go to town on the dangers of granite countertops and the Radon they produce.
So – are your granite worktops dangerous? Can your granite or quartz worktop kill you? In this article, we are going to try to deal with these questions.
The quick answer is that granite and quartz worktops create absolutely no significant increase in Radon gas in the home.
This has been our standard answer to the question for years, but we now have our own, independently-sourced and official data which proves the point. If that answer satisfies, then read no more – but if you are curious, feel free to read on.
What is Radon gas? Radon gas is both extremely rare and very common. That is because it is the product of the breakdown of Uranium-238 and Thorium-234 – two radioactive elements which are found in some fairly common rocks. It is rare because it doesn’t last long – if you had a jar full of it, every three days or so you would find that half had turned into other stuff on the way to being lead which isn’t radioactive at all.
But because it is a gas it is the one element in that breakdown chain from Uranium that can really cause you some harm. Breathing in Radon gas actually can increase the chance of lung cancer – especially for smokers and ex-smokers.
How common is Radon gas in homes? It varies greatly from country to country and region to region. Parts of the UK with uranium rich granite close to the ground’s surface can have surprising amounts of radon infiltrating into cellars and basements. Once it gets to well-ventilated ground level rooms, though, the gas tends to just blow away. The Public Health England Radon website has a detailed, scaleable map showing the chances that homes across the UK have high concentrations. Broadly speaking, that means some areas of the West Country and Southern Scotland.
On the Western Europe map to the left, please note that some countries’ data was not available for inclusion.
How does Radon gas get into the home? If your house is built on granite, near the surface, without a layer of airspaces in, say, hard core beneath, radon can come into your cellar through cracks and diffusion.
Does the granite in use for worktops produce radon gas? The answer is that it depends very much on the granite. But some stones, especially (apparently) some of the highly-coloured and pinkish rocks, do contain some of the elements which can go on to produce Radon. However – read on. Worktops are not bedrock, and the quantities involved together with the good ventilation in every kitchen makes the radon from worktops a total non-issue.
Do quartz worktops produce Radon gas? Quartz is man-made, but it is man-made using natural raw materials, so the question is a sensible one. Most quartz is produced using a good proportion of white quartzite – not really a radioactive rock at all. Some more colourful worktop materials can have granite offcuts in, though, so I will not totally rule out a tiny amount of radon. On the other hand, the plastic content and self-sealed nature of the product may not allow the molecules of gas to diffuse out anyway…
So are granite and quartz worktops dangerous? The amount of radon produced from worktops is tiny compared to the background amount which many British homes receive from the ground they are built on. In addition, higher concentrations of Radon, where they exist, are always in unventilated basements – not a place where you will find a kitchen, by and large. There is no evidence at all of significantly raised levels of radon in homes with granite worktops – there is no danger.
What about in your workshop and warehouse? We have many hundreds of slabs of granite and quartz in our storage areas. Among them are some of the highly-coloured stones which come, for instance, from South Brazil – a region known for higher radioactivity in its rocks. Do we have high levels of radon at Affordable Granite? Are our staff or visitors in any danger?
We have recently had a three month test for Radon levels in various parts of the factory and in our office. Public Health England set up sensors which were left running, in order to get good average readings over a period of time. I wondered if our least ventilated area – the old barn, which houses a good number of quite exotic slabs, would show a higher reading than the other, more open parts of the factory.
As I understand it, regulations kick in for workplaces when the Radon level is at 300 Becquerels per cubic metre of air. In homes, where you spend more time, Public Health encourages some action if the level is above 200 Bq/m3, with a target of 100 Bq/m3.
In all parts of our factory, including in the barn with its weaker ventilation, and in the presence of hundreds of slabs of granite and quartz, the level was never above 10 Becquerels per cubic metre. Our maximum is less than a tenth of the target value published by the government, and less than the average level in UK homes, at around 20 Bq/m3.
To put it another way, our factory, with its hundreds of worktops-in-waiting, does not have measurably more radon than in any typical Surrey home or workplace.
At Affordable Granite we take health and safety seriously. And we know that in some areas of the UK, Radon can be a challenge. The highest levels measured in, for instance, some Cornish basements have reached thousands of Becquerels per cubic metre.
But we are absolutely satisfied that our products do not constitute a radiation risk, either to our staff, who work with granite every day, or to our customers.
We are Affordable Granite, the leading granite installer in Surrey, Sussex and across the South East. We are committed to the highest standards of health and safety, and to sharing information freely and honestly. We have confidence in ourselves, and in our customers – that people who buy from us are intelligent and are looking to be informed and dealt with in a straightforward way. If you have any questions about Radon and would like to see our documentation from Public Health England, please don’t hesitate to contact us on 01293 863992 or by email on firstname.lastname@example.org/ .