crawl space radon sealing 3

https://radonretestaftermitigationbase.moderncairn.com/posts/why-a-radon-retest-after-mitigation-is-your-most-important-step

After testing, we found radon levels in the crawl space were way above safe limits, so we had to seal every crack and penetration in the concrete floor and walls with a thick, flexible epoxy coating to keep that radioactive gas from seeping up into the living areas.