Yes. Slab and basement homes are easiest to mitigate via sub-slab depressurization. Crawl spaces require sealing and a vapor barrier first. Pier-and-beam homes need different strategies entirely.
More detail
Sub-slab depressurization (ASD) is the EPA-preferred mitigation method and works on slab and basement foundations because there is solid concrete to drill a suction pit through and to hold negative pressure beneath. Crawl-space mitigation requires sub-membrane depressurization (SMD): the mitigator installs a reinforced 6-12 mil polyethylene barrier sealed to the perimeter walls, then creates suction beneath that membrane. SMD is more expensive ($1,800-$3,500 typical) than ASD because it requires the membrane installation. Pier-and-beam homes (rare in Cincinnati but present in some pre-1900 stock) require either sealing the entire underside with a barrier-and-fan approach or addressing soil gas at the source via sub-soil ventilation lines, which is uncommon and significantly more expensive. The on-site assessment identifies foundation type and writes the quote against the appropriate strategy. Cincinnati foundation-mix reality: roughly 60% of pre-1980 Cincinnati housing has full basements; another 25% has slab-on-grade or partial basements; the remaining 15% has crawl spaces or mixed foundations. Newer construction (post-1995) skews more heavily toward slab-on-grade in subdivisions and full basements in higher-end custom builds. All four foundation profiles have an established mitigation approach; the on-site assessment identifies which one your home needs.