MAH_2019

Protocol for Conducting Measurements of ANSI/AARST MAH 2019 Radon and Radon Decay Products in Homes 4 3.3 Choosing a Location Within a Room Detectors are to be placed in accordance with Table 3.3 . Note—The intent is to test in the general breathing zone. Table 3.3 Requirements for Test Locations Within a Room Detectors shall be located not less than: 3 feet (90 cm) from exterior doors and windows or other potential openings to the outdoors. 20 inches (50 cm) above the floor. 1 foot (30 cm) from the exterior wall of the building. 1 foot (30 cm) below the ceiling. 4 inches (10 cm) from other test detectors and objects that are above or to the side of the detector. Exception: Less than 4 inches (10 cm) is permitted for detectors that are not affected by close proximity to other objects. Confirmmanufacturer or laboratory requirements or recommendations prior to exercising this exception. Side-by-side detectors Detectors are to be not more than 8 inches (20 cm) from each other whenever seeking to use the average test result of two side-by-side detectors for mitigation decisions. Place detectors where not easily disturbed Informative Advisory —Select a position within the room where the detector(s) will not likely be disturbed, moved or have their performance altered during the measurement period. Detectors shall not be located: — inside closets, cabinets, sumps, crawl spaces or nooks within the building foundation. — near heat sources, such as on appliances, radiators, fireplaces or in direct sunlight. — near drafts caused by fans or heating and air conditioning vents or in enclosed areas of high air velocity such as mechanical/furnace closets. — within enclosed areas of high humidity such as bathrooms, laundry rooms and kitchens that are isolated from large open areas by partitions or other enclosures. Exception: Such locations should be avoided but are permitted for detector types that are virtually unaffected by high humidity. Confirmmanufacturer or laboratory requirements or recommendations prior to exercising this exception. Informative Advisory —Avoid placing detectors on or near objects that may produce radiation such as natural stone (e.g. rock collections, granite counter tops, hearths or slate pool tables).