MAH_2019

Protocol for Conducting Measurements of ANSI/AARST MAH 2019 Radon and Radon Decay Products in Homes 22 EXHIBIT 1 ADDITIONAL CLARIFICATION ON CLOSED BUILDING PROTOCOL REQUIREMENTS FOR SPECIFIC COMPONENTS Windows and Doors Broken windows or doors Seal closed Interior partition or stairway doors No special requirements Doors leading into a garage Keep closed (except for momentary entry and exit). Garage doors Pet doors (includes flap openings) Small Appliances Ceiling fans and portable fans Do not blow fans directly towards testing devices Window fans Remove or seal shut and do not operate Humidifiers and dehumidifiers Operate normally Central vacuum cleaner systems Crawl Spaces Passive crawl space vents The condition should reflect average yearlong operation Crawl space humidity control systems Operate normally Mechanical Systems Passive vents for combustion air makeup Leave open Fireplace dampers Close dampers or doors if practicable Combustion appliance fans Operate normally Fans installed in attics to ventilate only attic air and not air within the building. Return air ducts from forced air heating and/or cooling systems are under concrete floors Conduct at least one test when air handlers are active Mechanical Ventilation Systems that can temporarily ventilate with outdoor air for seasonal comfort or energy savings Window air conditioners Operate in recirculation mode only Evaporative cooling systems (e.g. swamp coolers) Do not operate and do not cover Energy recovery or heat recovery ventilators Operation of permanently installed ventilation systems that bring outdoor air into the home throughout the year is permitted to continue during the test so long as: a) the system is set to the lowest ventilation condition that occurs for any season, and b) all thermostats in the building are set to normal occupiable temperatures .