radon in basement

https://qqpipi.com//index.php/Why_Indoor_Air_Quality_Testing_Matters_More_Than_You_Think

Radon in basement is a serious concern because this radioactive gas seeps up from the soil and can accumulate to dangerous levels underground. Since basements are often poorly ventilated, the gas gets trapped, and long-term exposure is the second leading cause of lung cancer. Testing is the only way to know if your home has high radon levels, and it's a simple, inexpensive process. If levels are high, mitigation systems can vent the gas safely outside.