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What does it mean to building owners, investors and property managers?

US Department of Housing and Urban Development (HUD)

In 2013, two years after the Environmental Protection Agency (EPA) released the Federal  Radon Action Plan for single family homes, the HUD Office of Multifamily Housing issued a policy that requires Radon testing and mitigation – if testing shows Radon levels are 4 pCi/L or higher – for the following multifamily mortgage types:

 Housing Act / Mortgage types that now require Radon testing

Section 220 – New construction or substantial rehabilitation of mixed use projects in urban renewal areas

Section 221(d)(4) – New construction or substantial rehabilitation of multifamily rental or cooperative housing for moderate income families, elderly and the handicapped by profit motivated sponsors

Section 223(f) – Purchase or refinance of existing multifamily rental housing that does not require substantial repairs

Section 231 – Construction and substantial rehabilitation of rental housing for the elderly a\or disabled

Section 223(a)(7) – Refianance of original HUD insured mortgages. Adon testing in not required, but is encouraged

What does HUD require for multifamily testing?

  • HUD requires submission of a Radon Report with test results and details of any needed mitigation

  • HUD requires that all testing and mitigation be performed under the supervision of a certified or licensed Radon Professional

What are the accepted standards for Radon testing in multifamily buildings?

Until 2013, there were no guidelines for testing or mitigation of Radon in multifamily buildings. The American Association of Radon Scientists and Technologists (AARST) and the American National Standards Institute (ANSI) published the Protocol for Conducting Radon and Radon Decay Product Measurements in Multifamily Buildings. These published standards are now used by HUD as the required protocol with one exception:

The AARST-ANSI protocol for testing states that 100% of ground floor units must be tested in a multifamily building. However, the exception is that HUD requires at least 25% of randomly selected ground level units are to be tested for Radon.”

What are the accepted standards for Radon mitigation in multifamily buildings?

If Radon testing confirms levels of 4 pCi/L or higher, then HUD requires mitigation. The American Society for Testing and Materials ASTM) has developed 2 Radon mitigation standards, accepted by HUD. ASTM 2121 – 13 is the standard practice of installing Radon mitigation systems for existing, low-rise residential buildings and ASTM 1465-08a is the standard practice for Radon control options for the design and construction of new, low-rise residential buildings.

What does HUD require from the building owner or investor with regards to multifamily Radon testing?

  1. Comply with testing mandates as directed by HUD, state laws and lender requirements

  2. Ensure that all testing and mitigation is performed to the stated AARST and ASTM protocols and is performed under the supervision of a certified  and/or state licensed Radon Professional.

  3. Notify residents or forthcoming testing as per the ANSI-AARST guidelines.

  4. Notify residents prior to and after any mitigation activities

  5. Complete and submit a Radon Report certification of completion once Radon testing and/or mitigation are completed.

What are the responsibilities of property managers of multifamily buildings?

  1. Contract with certified and/or state licensed Radon Professional.

  2. Facilitate document and information exchange with the contracted Radon Professional.

  3. Facilitate tenant notification before testing and mitigation, including distribution of educational materials with explicit closed-building instructions to ensure an accurate test.

  4. Supervise all unit entries for the Radon Professional.

Are there HUD Radon requirements for condominiums?

Condominiums that operate as a single owner unit do not fail under the HUD Radon directive. However, a project that was built as condos but is now operating as a rental property would be subject to the policy.

What about Radon requirements for existing privately owned multifamily buildings

Radon testing and any needed mitigation for privately owned apartment developments are now subject to state and/or local jurisdiction.

Information and Radon standards from AARST can be found via this link: