MAH_2019

Protocol for Conducting Measurements of ANSI/AARST MAH 2019 Radon and Radon Decay Products in Homes 21 10.29 Valid Sample Time The period representing occupied conditions after stabilizing building conditions with initiation of the closed-building protocol. Examples of valid sampling times include: The period beginning 12 hours after closed-building protocols are initiated or 24 hours after activation of a radon mitigation system . Valid sampling time is further defined by all other related requirements within this standard including but not limited to maintenance of closed-building conditions throughout the test period for short-term testing. 10.30 Whole House Fan A fan that is temporarily activated to enhance occupant comfort by increasing ventilation for the majority of the heated and cooled envelope within a home. Common configurations include attic fans or window fans that exhaust air from the building to enhance the volume of outside air entering the home through open windows. 10.31 Working Level (WL) A unit of radon decay product concentration. One WL equals any combination of short-lived radon decay products in 1 liter of air that will result in the ultimate emission of 1.3 x 105 MeV of potential-alpha energy. It is approximately the alpha-particle energy released from the decay products in equilibrium with 100 pCi of Rn-222. 10.32 Working Level Month A unit of exposure to radon decay products or integrated radon decay product (WLM) concentration. One WLM is equivalent to an exposure to a radon concentration of 1 WL for a period of 1 working month of 170 hours.