CCAH Reducing Radon in New Construction of ANSI/AARST CCAH 2020 1 & 2 Family Dwellings and Townhouses 1 Reducing Radon in New Construction of 1 & 2 Family Dwellings and Townhouses SECTION 101 GENERAL 101.1 Purpose. The purposes of this standard shall be as follows: 1) To specify radon control methods and techniques for use in dwelling units to reduce indoor radon concentrations to below the National Action Level (NAL) of 4.0 pCi/L [150 Bq/m 3 ]. 2) To provide minimum requirements for the rough-In of radon control system components in new dwelling units under construction and activation of the radon control systems , if required. 3) To provide a model set of requirements for adoption by states and local jurisdictions. 4) To provide a means for authorized personnel to inspect and evaluate rough-In components of radon control systems and activated radon control systems in new construction. 101.2 Scope. This standard shall be applicable only to in newly constructed one- and two-family dwellings and townhouses. SECTION 102 LIMITATIONS 102.1 General. The requirements of this standard shall have limitations as indicated in Sections 102.1.1 through 102.1.6. 102.1.1 Results not guaranteed. The application of the requirements of this standard does not guarantee that the NAL or any other specific indoor radon concentration will be attained. 102.1.2 Alterations. The application of the requirements of this standard does not guarantee that the NAL or any other specific indoor radon concentration will be maintained where modifications, alterations, structural changes or additions to a dwelling occur. 102.1.3 ASD control. The specifications within this standard are limited to rough-In of radon control system components and activation of radon control systems based on the methodology of Active Soil Depressurization (ASD). 102.1.4 Soil-borne radon. The requirements of this standard address only soil-borne radon . Radon from other sources such as water and building materials are not addressed. 102.1.5 Prior systems. This standard shall not apply to radon control means that have been installed prior to the effective date of this standard. 102.1.6 Soil testing. This standard does not require or provide guidance for soil testing or analyzing the radon potential of a building site prior to construction of the building.