Sub-slab depressurization and sump-pit depressurization radon mitigation systems are more effective than sealing, membrane, block and beam, simple ventilation or filtration.
you can find the full study here: https://www.cell.com/heliyon/fulltext/S2405-8440(19)33681-3?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS2405844019336813%3Fshowall%3Dtrue