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page title goes here Risk Assessment

Radon Vapor Intrusion Screening Levels (RVISL) Calculator

Hover over any form section for instructions about the individual selection and requirements.


Select Screening Level Type


Select Target UMTRCA WL Standard





Select Exposure Scenario



Predict indoor air concentrations and WL from measured media concentrations








Select Site Info Type




Select Units




Groundwater Temperature (° C)



Attenuation Factor Sub-Slab (unitless)


For sub-slab soil gas, the recommended generic attenuation factor (αss) is 0.03.

Attenuation Factor Groundwater (unitless)


For groundwater, the recommended generic attenuation factor (αgw) is 0.001.

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