“Das Haus” is a German magazine about building and decorating houses. In a recent number, they have a contribution about the risks of Radon. In this contribution, they advice to use cellular glass as a seal against the radon gas. Hereunder, you will find a Google translation of the German article, which can be understood.
Radon is a radioactive noble gas naturally occurring in granitic soils. Especially in regions in Baden-Württemberg, Bavaria and Saxony, the gas is pouring out of the ground. In unsealed basements and ground floors, it can collect and affect the health of residents. Radiation experts warn of this danger: After smoking, radon is one of the leading causes of lung cancer.
You can not smell, feel, see or taste it. Nevertheless, radon is a serious health hazard. Barely noticed by the public, it is the second leading cause of lung cancer. In the Federal Republic of Germany, 2,000 people suffer from this cancer each year due to radon. In the EU, according to recent studies, 20,000 people per year are affected. Radon is still a source of danger asbestos or diesel soot.
Radon is a big radioactive strain on humans
But what is Radon anyway? Radon-222 is a naturally occurring noble gas produced from uranium disintegration processes. It is itself radioactive and (according to information video of the Federal Office for Radiation Protection) “the largest radioactive pollution for humanity”. Like uranium, it occurs in all soils and rocks – whether it poses a threat depends on the uranium content and the permeability of the soil. Typical areas with high radon concentrations in this country are parts of the Erzgebirge and the Bavarian Forest, the Vogtland and the Eifel. Particularly affected are areas with granite and volcanic rock or black slate.
One in ten households is exposed to too much radon
As a gas, radon spreads easily in the pores in the soil, from where it then enters the atmosphere. “Depending on the region, the air at a height of 1.5 m contains between 5 and 30 becquerels per cubic meter (Bq / m³) of radon a year,” explains Jan Henrik Lauer of the BfS Press Office. That alone is not a cause for concern, because the gas is quickly distributed in the outside air. The situation is different in buildings: leaking foundations, even along pipelines, can cause the gas to reach basement rooms and accumulate in the room air. The radon finds its way to the upper floors via cable ducts, stairs and leaking ceilings. According to the BfS, every tenth household is exposed to such an increased radon load of 100 Bq / m³.
Clues as to how high the burden of radon in a region is, call authorities such as environmental and health offices and the radon card of the BfS. But that does not say anything about the actual burden on your own home. Thus, the brochure “Radonschutz measures” (a planning aid for new and existing buildings of the state of Saxony) states: “Large differences are even within a plot … not uncommon”.
A soil survey can show the radon load
Certainty brings a Bodegutachten before buying a property. Based on this, it is already possible to prevent a radon load during the construction phase, eg with a foam glass seal or a radon drainage. Even in existing buildings, the danger is not helpless: already consequent airing, especially in the cellar area, is an important step to prevent the enrichment. Likewise, a sealing of the cellar door can be helpful. But if you also use the basement as a living space, larger steps are required. A general overview of such measures is provided by the Radonhandbuch Deutschland.
A Radon standard is currently being prepared to provide planners and contractors instructions. This will also be necessary because in 2018 a new Radiation Protection Act will come into force, which will also be dedicated to protection against radon. However, it incorporated the Radon reference value of 300 Bq / m³ from the EU. The Ministry of the Environment and the BfS already see a need for action for recreation rooms at radon concentrations above 100 Bq / m³ (annual mean). According to Jan Hendrik Lauer, it should be examined here “whether these can be reduced below 100 Bq / m³ with reasonable effort. In rarely or only temporarily used rooms, higher concentrations can be tolerated “. Whoever picks up a beer or potatoes from the cellar, does not need to be active.
Tenants are not entitled to protection against radon
However, while under the new law on workplaces there is an obligation not to permanently exceed the reference value of 100 Bq / m³, tenants in living spaces are not entitled to measures by the homeowner. Here you should look for the conversation with the landlord: Often, any necessary rehabilitation measures can be so connected to the Radonschutz that no excessive extra costs are caused. However, it is only possible to determine how high the values are by means of a professional on-site measurement over a longer period of time.
The most important measures against radon
You can hardly escape the radon. Most important measure: a professional long-term measurement. And then: ventilate consistently, seal off creeping paths, vacuum the gas.
Who informs about radon?
- The radon map with values from more than 2,300 measuring points nationwide shows how high the regional exposure to radon is. These can be found online at the BfS at https://www.bfs.de/DE/themen/ion/umwelt/radon/boden/radon-karte.html
- The environmental ministries of individual federal states also provide overview maps.
- The Radon manual with practical information from the BfS can be downloaded here: www.raumanalytik.de/media/radonhandbuchdeutschland.pdf
- The brochure “Radon-protective measures – planning aid for new and existing buildings” of the state of Saxony.
- Measuring instruments are available from specialist companies.