HUD changes radon testing requirements

HUD’s MAP Guide has been updated recently (2020). One significant change includes RADON testing of 100% of ground-contact units. Prior versions of the MAP Guide required 25%.

Radon is a breakdown product of Uranium which is naturally occurring. Since radon comes into buildings from below, ground-contact units/spaces typically will be worst-case in terms of radon levels, thus the 100% ground-contact testing requirement. HUD’s action level is 4 picocuries of radon per liter of air (pCi/L). If radon levels are equal to or greater than the action level (4 pCi/L), mitigation is required.

All testing must follow ANSI-AARST standards to include proper tenant notifications.

Finally, a condition of the Firm Commitment requires the borrower to comply with an Operation Maintenance and Monitoring (OM&M) plan for the duration of insured mortgage (OM&M plans are required when mitigation is required).

For more information, contact Scott Rifkin at


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