biostudies-literatureUnknown9(1)Stanley FKTRoy Romanow Provincial Laboratory Saskatchewan Health AuthorityAlberta Real Estate FoundationGouvernement du Canada | Health CanadaGouvernement du Canada | Canadian Institutes of Health ResearchCanada Research ChairsCIHRHuman-made buildings can artificially concentrate radioactive radon gas of geologic origin, exposing occupants to harmful alpha particle radiation emissions that damage DNA and increase lung cancer risk. We examined how North American residential radon exposure varies by modern environmental design, occupant behaviour and season. 11,727 residential buildings were radon-tested using multiple approaches coupled to geologic, geographic, architectural, seasonal and behavioural data with quality controls. Regional residences contained 108 Bq/m³ geometric mean radon (min < 15 Bq/m³; max 7,199 Bq/m³), with 17.8% ≥ 200 Bq/m³. Pairwise analysis reveals that short term radon tests, despite wide usage, display limited value for establishing dosimetry, with Scientific reports18472https://www.ebi.ac.uk/biostudies/studies/S-EPMC6890734biostudies-literatureRadon exposure is rising steadily within the modern North American residential environment, and is increasingly uniform across seasons.PMC6890734Innes DGGoodarzi AASalgia SRJacques WRTorr DBrenner DRWinquist BDIrvine JLStanley FKTfalseRadon exposure is rising steadily within the modern North American residential environment, and is increasingly uniform across seasons.Human-made buildings can artificially concentrate radioactive radon gas of geologic origin, exposing occupants to harmful alpha particle radiation emissions that damage DNA and increase lung cancer risk. We examined how North American residential radon exposure varies by modern environmental design, occupant behaviour and season. 11,727 residential buildings were radon-tested using multiple approaches coupled to geologic, geographic, architectural, seasonal and behavioural data with quality controls. Regional residences contained 108 Bq/m³ geometric mean radon (min < 15 Bq/m³; max 7,199 Bq/m³), with 17.8% ≥ 200 Bq/m³. Pairwise analysis reveals that short term radon tests, despite wide usage, display limited value for establishing dosimetry, with 2019-01-01T00:00:00Z2019 Dec2025-04-04T21:03:47.419Z2020-05-21T21:23:59ZS-EPMC68907343179686210.1038/s41598-019-54891-8