*American Radon Mitigation Inc. guarantees that the annual average radon level in the client's home will be 1.5 pCi/L or less for five years, beginning on the installation date, so long as all items on the bid are selected. The 1.5 pCi/L guarantee does not apply to homes with sub-slab ductwork, aftermarket drain tile, untreated crawl spaces, multi-family homes, or inaccessible air leaks to the soil.