RADON. January 2010 Greenfield Health Department. Mary Kapelis RN RS

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1 RADON January 2010 Greenfield Health Department Mary Kapelis RN RS

2 What is Radon? Radon is a colorless, tasteless and odorless gas. Radon is a cancer-causing, radioactive gas.

3 Where Does Radon Come From? Radon comes from the natural breakdown/decay of uranium in soil, rock and water. Radon gas enters a home through cracks in walls, basement floor, foundations and other openings.

4 Geology of Radon Uranium is present in all rocks, however, the amount of uranium varies. Some types of rocks have higher than average uranium contents. These include light-colored volcanic rocks, granites, dark shales, sedimentary rocks that contain phosphate, and metamorphic rocks derived from these rocks. Radon then moves through fractures and openings in the soil. Radon can be present in contaminated soils, i.e. uranium processing mills.

5 Health Risks Related to Radon Exposure Second leading cause of lung cancer. Smoking is number one. Smoking and radon exposure enhance the risk of lung cancer.

6 Health Risks: How Does Radon Cause Cancer? Radon and RDP (Radon Decay Products) are inhaled. Radon may be exhaled. RDP remain and adhere to lung tissue. Decay Products Po-218 and Po-214 emit alpha particles. Alpha particles strike the lung cells causing physical and chemical damage to the DNA.

7 PARENTS AND PROGENY OF RADON-222 Ra-226 Rn-222 alpha Po y 3.8 d 3 min alpha Pb min beta Th Bi min beta U E9 y Pb-210 alpha Po s IN THE GROUND 21 y IN THE AIR

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9 1. Radon comes from the ground or water. 2. Bronchial deposition of radon decay products. 3. Alpha energy delivered directly to cells. HEALTH RISK

10 Radon and Radon Progeny EST D. AVERAGE INDOOR RADON: 1.3 pcil

11 How does exposure to Radon compare to other risks?

12 What affects radon levels? Strength of source materials in soil Openings connecting indoor air to soil air Forces pulling radon into the building The amount of dilution with outside air Out-gassing from wells Frost or other factors that cap soil Concrete and asphalt pavement can also cap soil

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16 Cracks in concrete slabs Spaces behind brick veneer walls Pores and cracks in concrete blocks Floor-wall joints Exposed soil, as in a sump Weeping (drain) tile, if drained to open su Mortar joints Loose fitting pipe penetrations Open tops of block walls Building materials such as some rocks Water (from some wells)

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19 Prevalence of radon nationwide Wisconsin Milwaukee County Radon

20 Radon Map

21 Radon Zones Zone 1 counties have a predicted average indoor radon screening level greater than 4 pci/l (pico curies per liter) (red zones) Zone 2 counties have a predicted average indoor radon screening level between 2 and 4 pci/l (orange zones) Zone 3 counties have a predicted average indoor radon screening level less than 2 pci/l (yellow zones) Highest Potential Moderate Potential Low Potential

22 Estimated Percentage of Homes with Radon > 4 pci/l, Main Floor Year Average 48,000 (1995) vs 87,000 (2005) Measurements, by Zipcode

23 Wisconsin Measurements 2006 Milwaukee County Number of Measurements Zip code Total No # 4-10 pci\l # >10 pci\l Ave. pci\l High pci\l County Totals

24 How Do You Test For Radon? Short Term Test 48 to 72 hours. The test is done on the lowest lived-in level of the home. Long Term Test Test that remains in the home for more than 90 days. Long term test may last up to a year.

25 What Do The Results Mean? The average indoor radon level is estimated to be about 1.3 pci/l. The average outdoor radon level is about 0.4 pci/l. EPA Action Level is 4.0 pci/l.

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27 BRIEF REVIEW OF RADON MITIGATION AND RADON-RESISTANT NEW CONSTRUCTION

28 RADON-RESISTANT NEW CONSTRUCTION OMIT FAN, LEAVE SPACE FOR IT STACK THROUGH HOUSE INTERIOR BUILD WITHOUT OPENINGS; SEAL SUMP, CRACKS AND OPENINGS TO SOIL DEPRESSURIZED ZONE

29 RADON MITIGATION SYSTEM FOR EXISTING HOUSES: SUB-SLAB DEPRESSURIZATION (SSD) FAN SEAL CRACKS AND OPENINGS TO SOIL DEPRESSURIZED ZONE

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31 STACK TO ROOF CAN RUN OUTSIDE HOUSE. IT WILL BE DIFFERENT FOR NEW CONSTRUCTION

32 T dp RADON RADON AND DIFFERENTIAL PRESSURE vs TIME MITIGATION INSTALLATION Patt's., Oct 22 to Nov. 12; Mitigated Oct. 30, 1990 FAN ON TIME (NOON INDICATED) WHEN BASEMENT AIR PRESSURE (dp) GOES DOWN, RADON ENTRY INCREASES. THE DAY BEFORE STACK FAN FIRST TURNED ON, INSTALLERS VENTILATED BASEMENT.

33 DETAILS, PASSIVE STACK TOP VIEW DRAIN TILE LOOP CRAWL SPACE GRAVEL AVOID ALL FIGURES FROM ST. OF COLO. WEB SITE

34 COSTS SSD installation costs $1,000 SSD operation costs $ / yr

35 It s your family s Health. What could be more Important!

36 Radon Information Line LOW-RADON State of Wisconsin Web Site Important Information

37 Questions???? Comments!!!!

38 Thank You