MAH_2019

Protocol for Conducting Measurements of ANSI/AARST MAH 2019 Radon and Radon Decay Products in Homes 17 the potential for unusual or sizable variations in indoor radon concentrations. The most common examples are buildings found in limestone-rich areas where groundwater has eroded passages in the underlying rock (karst) or areas with faulting, which could allow radon to be easily transported. A State Radon Office , geological authority or other local authority may have information on local experiences with any unusual fluctuations in radon concentrations.” 8.5.10 Statement of Test Limitations Informative Advisory —The report should describe the general limitations of the test. An example is the following: “There is an uncertainty with any measurement result due to statistical variations and other factors such as daily and seasonal variations in radon concentrations. Variations may be due to changes in the weather, operation of the dwelling, or possible interference with the necessary test conditions.” 8.6 Maintaining Records Because the effects of radiation exposure may not become apparent until many years have passed, measurement reports shall be kept for a minimum of 6 years or as additionally required by the jurisdiction where the test is conducted. 9.0 RADON DECAY PRODUCT MEASUREMENTS (RDP) 9.1 Professional Training Is Required The use of RDP measurement devices requires specific training to properly account for a wide variety of site-specific conditions and technology considerations. Individuals placing, retrieving and analyzing RDP detectors shall have demonstrated a minimum degree of appropriate technical knowledge and skills specific to RDP measurement: a) as established in certification requirements of the National Radon Proficiency Program (NRPP) or the National Radon Safety Board (NRSB); and/or b) as required by statute, state licensure or certification program, where applicable. 9.2 Units of Measurement and Action Level When radon decay products are measured, the unit of measurement provided by devices is to be in Working Level (WL). Note—Historically the action level has been cited as 0.02 WL. Section D of the attached MAH Companion Guidance provides more descriptive information. 9.3 Gas Measurement Also Required When the test is for determining the need for mitigation in homes, RDP measurement devices shall not be used unless accompanied with a simultaneous radon gas measurement. 9.4 Reporting Requirements 9.4.1 Conventions RDP results reported in Working Level (WL) shall be reported to no more than three figures after the decimal (e.g. 0.012 WL). 9.4.2 Conversions Conversions shall not be made betweenmeasurements of radon gas (pCi/L or Bq/m ³ ) andmeasurements of radon decay products (WL) for determining if mitigation is needed.