Geiger counters can't measure for radon in granite

Videos using Geiger counters to measure for radon in granite are typically done for dramatic effect. While Geiger counters can see radiation in granite, they cannot measure for radon because they do not differentiate between the multiple radioactive elements (some of which pose no risk, such as Potassium) found in granite. Hence, they typically over-respond. Provided by the Radon Information Center at www.radon.com

Post Tension Slab