Radon - an invisible threat

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Changed on: 21.11.2016

Effects of Radon

Radon is a naturally occurring, radioactive gas. It is odourless, tasteless and colourless and is a decay product of uranium. Since uranium is found almost everywhere as a trace element (rock, soil, building materials), radon also occurs everywhere.

Inhabited buildings act - especially during the cold season - as suction cups. The stack effect causes a small negative pressure in the lower part of a building and radon-laden soil gas is drawn into the house.

Radon and its radioactive decay products (polonium, bismuth, lead) enter the lungs when air is inhaled. About 10 percent of all lung cancer deaths in Austria are due to the exposure to radon and its decay products.

Although radon is a naturally occurring noble gas in the soil, it must be seen as technologically induced indoor pollutant due to its possible accumulation in buildings.

Radon is a naturally occurring, radioactive gas. It is odourless, tasteless and colourless and is a decay product of uranium. Since uranium is found almost everywhere as a trace element (rock, soil, building materials), radon also occurs everywhere.

Inhabited buildings act - especially during the cold season - as suction cups. The stack effect causes a small negative pressure in the lower part of a building and radon-laden soil gas is drawn into the house.

Radon and its radioactive decay products (polonium, bismuth, lead) enter the lungs when air is inhaled. About 10 percent of all lung cancer deaths in Austria are due to the exposure to radon and its decay products.

Although radon is a naturally occurring noble gas in the soil, it must be seen as technologically induced indoor pollutant due to its possible accumulation in buildings.

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(Source: Statistik Austria, 2011)

How to protect yourself against Radon?

How can I protect myself against radon?

1. Inform yourself

Seek relevant information, look up your municipality on the interactive Austrian radon potential map and watch the animated video on radon at the radon homepage of the BMLFUW at www.radon.gv.at.

2. Test your home for radon

Taking a radon test is the only way to be certain about the radon exposure for an existing building. The measurement detectors are sent by mail - the measurement is simple and inexpensive. Radon tests in homes are currently free in Austria. A radon measurement can be obtained directly from the National Radon Centre of Austria (radonfachstelle@ages.at).

3. If necessary: Take action!

If elevated radon concentrations are detected, the problem can often be fixed with relatively simple measures. Do not operate an ostrich policy - but take responsibility for your health and that of your family.

4. Take preventive measures

If you are planning to build a new building or make alterations to the existing building, include simple radon protection measures in your plans. Preventive radon protection is cheaper, more effective and easier than retrospective radon remediation measures.

The Austrian Radon map

The Austrian Radon map

Die Österreichische Radonpotenzialkarte stellt das berechnete Radonpotenzial jeder einzelnen österreichischen Gemeinde in den Klassen 1 - 3 dar.

The current Austrian radon map was prepared on the basis of more than 20,000 radon tests in homes. It provides information on where elevated radon concentrations in buildings in Austria can be expected. About 500 municipalities have an elevated radon potential.

The radon potential for each municipality can be looked up on an interactive map on www.radon.gv.at, the radon information site of the Austrian Federal Ministry of Agriculture, Forestry, Environment and Water Management (BMLFUW). There you will also find further recommendations about the measurement of radon and for structural protective measures depending on the radon potential.

Radon measurement

Radon measurement

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Instruments for passive radon measurement: different dosimeters and an electret.

The radon concentration in indoor air can be measured relatively easily and reliably. The reference levels for the annual average radon concentration in Austria are 400 Bq/m³ for existing buildings (action level) and 200 Bq/m³ for new buildings (target level).

To obtain a measurement result, which can be used for comparison with the reference level, the radon test must be carried out according to the Austrian Standard ÖNORM S 5280-1. It has to be measured for a minimum period of 3 months and at least half of this period must be within the heating season. A meaningful annual average can only be derived from results which meet these requirements. Further information on radon measurement can be obtained from the National Radon Centre of Austria (radonfachstelle@ages.at).

Structural radon protection

Structural radon protection

Simple radon protective measures should be considered when planning a new building

In all federal states except Salzburg radon protection in buildings is regulated by the federal building legislation.

Simple and inexpensive preventive measures are the best protection against high radon concentrations in new buildings. Basic measures are generally recommended. In the communities with elevated radon risk further measures are advised.

Preventive measures are much simpler, more effective and more cost-effective than the subsequent radon remediation of a residential building. Basically, the tighter the building envelope is against the soil, the lower is the radon risk. New buildings should be designed in a way that the average radon concentration does not exceed 200 Bq/m³.

In the Austrian Standard S 5280-2 "Radon - Technical precaution measures in buildings" four types of prevention are identified. The type depends on the radon potential classification of the community and the type of building (e.g. basement, inhabited rooms in direct contact with the ground). The required radon protection measures are described for each scenario. They range from building in accordance with existing regulations for water penetration and rising damp to the installation of a radon drainage system (perforated pipes in the gravel bed below the foundation). The costs of preventive measures in new buildings in single-family homes usually do not exceed € 1.800 ,-.

After completion of the building, a control measurement is recommended.

The brochure on preventive measures against radon in new buildings, published by Austria, Switzerland, southern Germany and South Tyrol provides more Information.

Radon remediation options for existing buildings

If the radon concentration exceeds the action level of 400 Bq/m³, this can be resolved through proven remediation measures for the building. The measures range from sealing components such as the bottom slab to the suction of the soil air from below the slab.

The costs of mitigation strongly depend on the required action. While simple measures - which often can be carried out by the house owner themselves - start at around just € 100, -, the costs can go up to € 5.000,- in case of complex conditions.

Consideration of radon protection measures in the course of a general renovation or thermal retrofitting

Refurbishments offer a good opportunity to reduce the radon concentration. Therefore it is essential to test the house for radon before the general renovation starts. When elevated radon levels are found, protective measures should be considered.

Various studies show that thermal retrofitting measures which increase the tightness of the building envelope can increase the indoor radon level. To avoid any bad surprises after thermal remediation, one should consider the radon situation in advance and, if necessary, take further action.

Radon-exposed workplaces

Radon-exposed workplaces

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Water basin in an Austrian water supply facility

At certain workplaces very high radon concentrations may occur. The limitation of radon exposure and the protection of employees are regulated by the Ordinance on Exposure due to Natural Radiation Sources (NatStrV) and apply to workplaces such as:

  • Water supply facilities
  • Mines
  • Visitor mines and show caves
  • Radon spas

In Austria these companies need a dose assessment of the employees and have to communicate the result to the authority.

AGES is an authorized dose monitoring body

In our capacity as an/the authorized dose monitoring body we offer dose estimates and assessments. For more information and details, please contact us via radon@ages.at.

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