What's with radon mentions here and at AirGradient pages? Where would that come from, is this a US thing? Reminds me of 'asbestos-free cereal' xkcd joke. EDIT:

What's with radon mentions here and at AirGradient pages? Where would that come from, is this a US thing? Reminds me of 'asbestos-free cereal' xkcd joke. EDIT: > Radon is the second leading cause of lung cancer in the United States. Nationally, the EPA estimates that about 21,000 people die each year from radon-related lung cancer. Only smoking causes more lung cancer deaths. You gotta be kidding me, that's wild. https://www.epa.gov/radiation/what-radon-gas-it-dangerous https://www.epa.gov/radiation/what-radon-gas-it-dangerous