1	Common Ground For Health Risk Reduction Airborne particulates impact all three areas. Improvements in air quality can benefit radon
2	Focus on Radon Decay Products Came from identifying methods for mitigating difficult buildings. Inaccessible crawl spaces Sub-slab return ducts Overpowering HVAC systems Provides additional tools for measurement and mitigation contractors.
3	Why Radon Is A Concern Radon as a gas can enter indoor environments Radon decay products are created from radon Electrostatically charged Attach to lung tissue Quickly attach to surfaces or particles Source of health effects of radon exposure Measured in Working Levels (WL) Can be expressed in terms of equilibrium equivalent radon (pCi/L) for easy comparison.
4	Radon and Radon Decay Products Represent a Mixture of Gas and Particulates in the Air Radon is inhaled and then exhaled No accumulation Little health risk Radon decay products are inhaled Adhere to lung tissue Can cause damage to lungs before particles are expelled. Primary health risk
5	Charged Radon Decay Products Readily Attach to Airborne Particles and Surfaces
6	Equilibrium Factor (EF): Ratio of Suspended Decay Products to Total Conditions that decrease suspended RDPs and hence decrease EF Air Circulation Increases contact with physical objects such as walls and furniture Once attached, they are fixed and no longer present a risk Media Air Filters reduce suspended RDPs and hence EF Filters out radon decay products and particles to which they are attached Conditions that increase suspended RDPs and hence increase EF Stagnant indoor air Suspended dust, smoke Allows preferential attachment to airborne particles rather than walls More available for inhalation
7	Degree of Plate-Out Affects Exposure for Same Radon Gas Level
8	0.02 Working Levels Established as Standard for Uranium Mill Tailings Clean-up (UMTRCA)
9	Radon Gas Measurement Used as Surrogate Estimate of Risk RDP guidance is 0.02 WL of radon decay products Historical guidance 40 CFR - CHAPTER I –Part 19 § 192.20 cites 0.02WL If one assumes an equilibrium factor (50%) one can estimate RDP exposure from less expensive gas measurement Allows for less expensive consumer measurements
10	Radon Decay Product and Radon Instruments Used Continuous Monitors Femto-Tech 510 passive CRM Thompson Nielson active CWLM
11	Equilibrium Factors Guam
12	Equilibrium Factors Tokyo
13	Airborne Particulate Levels
14	Equilibrium Factors Colorado
15	Correlation Between Ambient Particulate Levels and Equilibrium Factor
16	Air Circulation Reduces Radon Decay Products
17	Elevated Radon - Low Radon Decay Products Hotel (Rocky Mountains)
18	Impact of Episodes of High Indoor Particulates (Home – Colorado)
19	Particulate Filtration Approaches (Reducing RDPs Rather than Radon) Installation Whole house Part of FAU Stand-alone consoles Typically requires use of HVAC contractor Requires special post-mitigation testing methods Reduces Radon decay products Asthma triggers Allergens
20	Continuous Measurements Before and After Activation of Filter (House)
21	Whole House High Efficiency Filter
22	Unattached vs Attached Analogy No Air Filtration 100 Flying insects with stingers 95 Bees 5 Wasps 5% Wasps ≈ 5% unattached fraction
23	Unattached vs Attached Analogy (contd.) With Air Filtration 5 Flying insects with stingers: 4 Bees 1 Wasp 20% Wasps ≈ 20% unattached fraction
24	Previous Studies Casted Doubt on Air Cleaners But Recent Studies and Health Models that Differentiate Dose with Particle Size Say Otherwise
25	Radon Decay Product Technologies (Measurement) RDP measurement methods provide additional tool for characterizing risk. Buildings with high air circulation Schools, Commercial buildings Homes with forced air systems ASHRAE 62.2 Buildings in high or low ambient particulate levels Will not replace radon measurements! Another arrow in the quiver
26	Radon Decay Product Technologies (Mitigation) Particulate Reduction Technologies Can provide additional IAQ benefits Will not replace active soil depressurization! Provides additional alternatives For difficult to mitigate buildings Schools, homes and commercial buildings
27	Will Radon Decay Product Criteria and Approaches Cause Confusion? Experience in Region 8 and 9 says it will not. References have been in documents historically EPA, states Health studies reference RDPs. 40 CFR 192.2 establishes 0.02WL RDPs as indoor clean-up standard. Homeowners understand it! Can easily be expressed in equivalent pCi/L. Homeowners like options for mitigation that can treat other things and add additional value.
28	Particulate Reduction is Common Ground For Health Risk Reduction Indoor is air improving Outdoor air is improving Programs are making a difference!
29	Is Radon Decay Product Measurements an Acceptable Procedure? Yes, EPA recognizes 2 testing procedures Radon decay products Radon gas “If all factors are equal the direct measurement of radon decay products is the preferable approach”. ...provides the most accurate assessment of health risk