Map redesign leads to 72% rise in people saying they would test for radon gas

Householders are more willing to test their homes for radon gas when the risk is shown to them using a redesigned official map. In an experiment, funded by the Environmental Protection Agency (EPA) and conducted by the ESRI’s Behavioural Research Unit, the redesign led to a 72% jump in people saying they would test for radon.

Although radon exposure in homes can cause lung cancer, the study found that 90% of people don’t know the risk in their area. Testing the level of radon gas in homes is easy, but the large majority of householders don’t do it.

The researchers tested 16 different maps in an online experiment involving 1,700 adults. Maps varied in subtle design features based on the psychology of risk perception. All the new maps outperformed the then in-use EPA map, increasing appreciation of the risk and willingness to test. The best performing map has now been adopted by the EPA.

One interesting aspect of the study was that while people said that they disliked maps that used statistics (e.g. “1-in-5 homes at high risk”), these maps led to a much higher willingness to test for radon. Colour and the number of risk categories on maps mattered too. 

“In some areas, as many as one-in-five homes are at risk, but most people don’t know their level of exposure,” said Dr Shane Timmons of the ESRI’s Behavioural Research Unit. “Radon has no colour or smell, so the only way to tell if it is present is to test your home. Our findings show that how risk from radon is communicated – particularly using statistics that people may not like – can motivate people to test their home.”

Speaking about the radon map, Alison Dowdall, EPA said:

“Radon is a serious public health issue and is linked to about 350 cases of lung cancer each year in Ireland.  The new EPA map provides clear information on radon risk and makes it easier for people to understand the risk where they live and to take action. Radon is easy to test for and easy to fix, so learning more about your risk and how you can protect you and your family is critical. We would encourage all householders and businesses, especially those in high radon areas, to test for radon.”