MALB_2014 with 1-21 Revisions

Conducting Measurements of Radon and Radon ANSI/AARST MALB-2014 with 1/21 Revisions Decay Products in Schools and Large Buildings 23 Test results to be regarded as a more accurate reflection of occupant exposure to radon hazards shall be those that most closely align to the predominant normal occupied building operating condition for the location tested, as defined in Section 2.7.2 . When conducting confirmation testing: a. the testing shall be conducted under building conditions that are representative of the predominant normal occupied building operating condition , as defined in Section 2.7.2 . b. testing shall be initiated within 1 year subsequent to initial testing unless the evaluation is relative to older, historic test results; and c. the evaluations shall be permitted based on data from short-term or long-term test devices or data from evaluations of occupied versus unoccupied radon concentrations. 7.3 Post-Mitigation Testing Protocol The following procedures are required for determining if additional mitigation efforts are warranted. 7.3.1 General procedures—Post-mitigation testing One or more short-term test devices shall be deployed at each test location to evaluate the effectiveness of the mitigation efforts. These measurements shall be conducted no sooner than 24 hours after activation of a mitigation system fan or completion of other mitigation efforts. In addition, closed- building conditions, in accordance with Section 4 , shall be maintained 12 hours prior to and throughout the test period. Testing shall be either: a) postponed until both conditions are met, or b) extended if testing with a continuous monitor where device features or other methods shall be used to obtain an average reading that represents no less than 46 hours of contiguous data collected after both conditions are met. 7.3.2 Clearance Testing Clearance testing to verify all portions of a building are below the action level shall comply with all requirements in a) and b) of this Section 7.3.2 . a) Test locations 1. Test locations shall include all ground-contact dwellings and non-residential rooms, in accordance with Section 3 , to include not less than 10% of the dwellings and non-residential rooms on each upper floor; and 2. Where any active soil depressurization (ASD) system exhausts below the roof, a test shall also be conducted in the room(s) immediately adjoining the outside exhaust location. b) Clearance testing—Failed locations Where clearance testing reveals a need for additional mitigation efforts, testing specific locations after additional mitigation efforts shall be sufficient for meeting clearance test requirements if the following requirements are met: 1. Where the mitigation method is active soil depressurization (ASD) and the mitigated locations are served by individual HVAC systems described in Exhibit 6 for Group 1 Basic Heating and Cooling : Testing shall include all locations where clearance testing revealed elevated radon concentrations. 2. Where mitigation methods are based on passive mitigation efforts: Testing shall include all locations where clearance testing revealed elevated radon concentrations.