MW-RN Protocol for the Collection, Transfer and ANSI/AARST MW-RN 2020 Measurement of Radon in Water 1 Protocol for the Collection, Transfer and Measurement of Radon in Water SECTION 1.0 PURPOSE AND SCOPE 1.1 This standard of practice contains minimum requirements and guidance for measuring radon in water that enters a building through groundwater supplies for determining if mitigation is necessary to protect current and future occupants of dwellings and other buildings. This standard includes procedures for the collection and transport of water samples, as well as protocols for the quantitative transfer of the sample to a measurement device to determine radon concentrations in water. This standard includes the U.S. EPA-accepted analytical methodologies, liquid scintillation and alpha- scintillation cells, along with essential information on use of electret ion chambers and acknowledgement of continuous radon monitors. A structure for defining a national reference for calibration and quality control, in lieu of a federally- recognized reference, is provided, as well as recommended action levels and acknowledgement of current state-recommended action levels. 1.2 Limitations 1.2.1 This document is not intended to address all detailed technical aspects of measurement technology or quality assurance. 1.2.2 Analytical methods that may be in current use shall successfully complete intercomparison or proficiency tests prior to routine use and reporting of results. 1.2.3 While this consensus document provides current best practices, individual states may require alternate sample collection, transport, preparation, and/or analysis procedures. Adherence to this standard does not guarantee or supersede compliance with regulations of any federal, state, or local agency with jurisdiction where testing is performed. 1.2.4 Application of the procedures to matrices other than drinking water may produce adverse results. 1.3 Significance of use This document is intended to aid water-supply owners/managers, residents and staff, professionals, state radiation control programs or anyone involved in the measurement of radon in water supplies to assess the need for mitigation and to provide radon risk information for the benefit of occupants. This standard addresses the needs of citizens, radon service providers, property owners, residence/facility managers, consultants, manufacturers, and regulators concerned with proper radon measurements in groundwater supplies. 1.4 Applicability 1.4.1 The terms “Note” and “Informative Advisory” indicate provisions considered helpful or good practice, but which do not contain a mandatory requirement. 1.4.2 These standards of practice can be adopted as requirements for contractual relationships or adopted as recommendations or requirements of an authority or jurisdiction such as for private proficiency programs, a state radon program, or other governmental body.