Radon & Radon Decay Product Measurement Course

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Radon & Radon Decay Product Measurement Course Radon & Radon Decay Product Measurement Course Center for Environmental Research & Technology, Inc. 1032 N Wahsatch Ave • Colorado Springs, CO 80903 800‐513‐8332 • www.certi.us Radon & Radon Decay Product Measurement Course Chapter 1: Overview Center for Environmental Research & Technology, Inc. Radon and Radon Decay Product Measurement Course Chapter 1: Overview Radon and Radon Decay Product Measurement Course Developed by the Center for Environmental Research and Technology, Inc. ©© CERTI CERTI 20152015 Radon and Radon Decay Product Measurement Course Chapter 1: Radon Overview Radium Uranium Center for Environmental Research and Technology, Inc. © CERTI 2015 Radon Created from Breakdown of Natural Deposits of Uranium and Radium Radon is a gas It is naturally occurring It is inert It cannot be seen or smelled Radon It enters a building from the soil beneath Radium Uranium © CERTI 2015 Copyright © Center for Environmental & Research Technology, Inc. 1994, rev 2015 1 Radon and Radon Decay Product Measurement Course Chapter 1: Overview How Is Radon Drawn Into A Building? Vacuum Exhaust systems Thermal stack effects 80 Radon pCi/L 60 40 20 Vacuum (pa.) 0 1234 Days © CERTI 2015 Radon Can Be Elevated in: Low Radon Potential Homes New homes Old homes Leaky homes Homes without basements Unless you live on a houseboat or in a tree house, Apartment buildings your home can have elevated Schools levels of radon! Offices © CERTI 2015 Radon Measurement Units Radon in air is measured in terms of: picoCuries per liter of air (pCi/L) Curie: the amount of radiation generated from 1 gram of radium One pico Curie: • One trillionth of a curie • 2.2 disintegrations per minute Radon can also be measured in units of Bq/M 3 Becquerel per cubic meter SI units (Canada and Europe) 37 Bq/M 3 = 1 pCi/L © CERTI 2015 Copyright © Center for Environmental & Research Technology, Inc. 1994, rev 2015 2 Radon and Radon Decay Product Measurement Course Chapter 1: Overview EPA & Surgeon General Recommend That People Not Have Exposures Above 4 pCi/L On A Long-Term Basis Long-term exposure to radon increases the potential for Lung Cancer © CERTI 2015 Radon Reference Levels Situation U.S. Action Level 4.0 pCi/L Average Outdoor Radon Levels 0.4 pCi/L Average Indoor Levels 1.25 pCi/L Level below which most homes can be mitigated 2.0 pCi/L % U.S. Homes Above 4 pCi/L 15 % (1 in 6) Guidance Levels 6.0 5.4 • Canada: 200 Bq/m3 4 4.0 • 200/37 = 5.4 pCi/L 2.7 • World Health Org: 100 Bq/m3 2.0 • 100/37 = 2.7 pCi/L Radon pCi/L) 0.0 Canada/Europe U.S. WHO © CERTI 2015 EPA Radon Zone Map EPA: 1993 Based on geology and survey results Expected short term radon (pCi/L): Zone 1 > 4.0 Zone 2 > 2 < 4.0 Zone 3 < 2.0 Many parts of the country have radon concerns! All Homes should be tested! © CERTI 2015 Copyright © Center for Environmental & Research Technology, Inc. 1994, rev 2015 3 Radon and Radon Decay Product Measurement Course Chapter 1: Overview Radon Distribution Radon enters from beneath foundation and travels upward Diluted with outdoor air infiltrating building Reduces exposure on upper levels If radon is less than 4 pCi/L in lower level, one can say with reasonable confidence that upper floors are also less than 4 pCi/L Radon levels are typically highest in lowest level If not, an unusual entry mechanism may exist © CERTI 2015 Test Purpose Dictates Conditions Radon Potential: Occupant Exposure: Short-term test Long-term test Typically 2-5 days Typically 91 days to 1 year Closed building conditions Normal lived in conditions 12 hours prior to and all without special closed building during test conditions. Device deployed on lowest Device deployed on lowest occupiable level of home. occupied level of home. Commonly used at time of Commonly used outside of resale. resale, or as basis of escrow fund release. © CERTI 2015 Common Short-Term Passive Test Devices Used to determine radon potential Activated Charcoal Commonly used at time of sale Deployed for 2-5 days Deployed by consumers and professionals alike Electret Ion Chamber © CERTI 2015 Copyright © Center for Environmental & Research Technology, Inc. 1994, rev 2015 4 Radon and Radon Decay Product Measurement Course Chapter 1: Overview Continuous Monitors 6 5 4 3 2 1 0 Unusual swings can help identify Provides hourly measurements concerns Interpretation based upon average Variations can indicate tampering © CERTI 2015 Successive 2-Day, Short-Term Measurement Results in Same House Over a three-month period, short-term real estate style 7 tests varied from 1.9 to 6.0 pCi/L. 6 5 4 3 2 2-Day Averages (pCi/L) Averages 2-Day 1 0 Average for entire period was 3.8 pCi/L Source: Dr. Dan Steck, Minnesota Radon Project Jan-March 1995 © CERTI 2015 Long-Term Tests Indicate Occupant Exposure Placed for a minimum of 91 days No special closed building conditions If result is equal to, or greater than 200 Bq/m3, mitigation is recommended Alpha Track Detector Electret Ion Hang at least 12 inches Chamber down from ceiling © CERTI 2015 Copyright © Center for Environmental & Research Technology, Inc. 1994, rev 2015 5 Radon and Radon Decay Product Measurement Course Chapter 1: Overview Test Location Depends on Purpose Lowest lived in Non-Real Estate Suitable for Real Estate Occupancy Lowest lived in Bedroom Bedroom Kitchen • Choose occupied room YES YES NO Garage • Only 1 room necessary NO Bedroom Closet Living Room Bathroom NO YES YES NO © CERTI 2015 Test Placement Within A Room* Breathing Space Away from areas of spatial highs or lows Where it will not be disturbed Ceiling Obstacle Minimum 12 inches Distance From (inches) Wall 3 feet from Opening (window or door) Floor 20 Interior 4 Ceiling* 12 inches Exterior: Interior wall 4 12 inches 20 inches Exterior wall 12 Floor Other objects 4 Minimum Distances from Features * AARST Protocol not in EPA Protocols * Regardless of test duration or device © CERTI 2015 Measurement Strategy: EPA Citizen’s Guide (Homeowner) Short-Term Test Step 1 Equal to, or No greater than 4 pCi/L? No Mitigation Yes ST > 8 pCi/L ST <8 pCi/L Step 2 Follow-up Test Repeat Short-Term Long-Term Test No Average of Results of No Yes Yes No No Mitigation 1st and 2nd results long-term test Mitigation Recommended at or above at or above Recommended 4pCi/L? 4 pCi/L? Mitigate Home © CERTI 2015 Copyright © Center for Environmental & Research Technology, Inc. 1994, rev 2015 6 Radon and Radon Decay Product Measurement Course Chapter 1: Overview Real Estate Testing Option: Simultaneous Tests Two Simultaneous Tests YES NO Mitigation Average of Both No Mitigation Recommended Tests > 4.0 pCi/L Recommended © CERTI 2015 Real Estate Testing Option: Sequential Testing Initial Short-Term Test 1 Second Short-Term Test 2 YES NO Mitigation Average of Both No Mitigation Recommended Tests > 4.0 pCi/L Recommended © CERTI 2015 Real Estate Testing Option: A Single Continuous Monitor 48 hour test with Continuous Monitor measures and reports in increments of 1 hour or less Mitigation YES NO No Mitigation Average > 4.0 pCi/L Recommended Recommended © CERTI 2015 Copyright © Center for Environmental & Research Technology, Inc. 1994, rev 2015 7 Radon and Radon Decay Product Measurement Course Chapter 1: Overview Radon Mitigation Overview (Movie Clip 11 min) © CERTI 2015 Radon Mitigation Works! 10 Mitigation System Off Mitigation System ON 9 8 7 6 5 4 3 EPA Guidance Radon (pCi/L) Radon 2 1 0 1:00 4:00 7:00 1:00 4:00 7:00 2:00 5:00 8:00 16:00 19:00 22:00 10:00 13:00 16:00 19:00 22:00 10:00 13:00 16:00 19:00 22:00 Hour © CERTI 2015 Is getting below 4.0 pCi/L the only consideration? © CERTI 2015 Copyright © Center for Environmental & Research Technology, Inc. 1994, rev 2015 8 Radon and Radon Decay Product Measurement Course Chapter 1: Overview Discharges Should Be Above Roof Discharge © CERTI 2015 Discharges to be Away From Openings Discharge © CERTI 2015 Discharges Carry Moisture © CERTI 2015 Copyright © Center for Environmental & Research Technology, Inc. 1994, rev 2015 9 Radon and Radon Decay Product Measurement Course Chapter 1: Overview Fan Location EPA Standards: Fans Should be Outside Living Space Leakage on positive pressure side of fan can introduce radon into building © CERTI 2015 Use Solid PVC! Dryer vent in Attic?? Caused Leak Through Ceiling © CERTI 2015 Unique Systems © CERTI 2015 Copyright © Center for Environmental & Research Technology, Inc. 1994, rev 2015 10 Radon and Radon Decay Product Measurement Course Chapter 1: Overview Electrical Disconnects Tapping into existing circuits Non-rated fans Licensed electrician? Fan supports Permits? © CERTI 2015 Labeling What should it say? How durable should it be? Where should it be? © CERTI 2015 Documents Citizen’s Guide Homebuyer’s and Consumers Guide to Seller’s Guide Radon Reduction Available within course and at EPA website © CERTI 2015 Copyright © Center for Environmental & Research Technology, Inc. 1994, rev 2015 11 Radon and Radon Decay Product Measurement Course Chapter 1: Overview State Programs Many States have active radon programs that may have their own disclosure information and even different measurement protocols. Several States have their own certification programs that may require separate exams and certification application. California Iowa New Jersey Delaware Kentucky Ohio Florida Maine Pennsylvania Illinois Nebraska Rhode Island Indiana New Mexico West Virginia © CERTI 2015 Certifications for Radon Professionals © CERTI 2015 Residential Measurement Provider: Standard Services (S) Place radon measurement devices (in homes) analyzed by NRPP certified laboratories or analytical service providers Interpret results for homeowners Two year certification Renew with CE Courses Certification initially requires course and exam passage Renewal requires continuing education to maintain © CERTI 2015 Copyright © Center for Environmental & Research Technology, Inc.
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