Radon 101 & Testing Twa-le Abrahamson-Swan Spokane Tribal Air Quality Department

Superfund Site: Midnite Uranium Mine Contaminants: radionuclides and heavy metals in acid mine drainage, radioactive decay, and particulate transport in air, surface water, and groundwater. In as soon as two years, millions of tons of contaminated material will be moved using heavy equipment. A new water treatment plant will be built. Remediation is expected to take 8 to 10 years.

What Is Radon –222 (radon)? Radon is a gas It is naturally occurring You can not see or smell it It enters buildings from the soil beneath them Uranium Radium Radon 1,600 years 4.5 billion years 3.8 days

Things to know about radon Naturally occurring Gas Undetectable by human senses ◦ Colorless, Odorless, Tasteless Radioactive Does not chemically react No static electrical charge. Will not adhere to other atoms or surfaces.

Average Contributions From Radon Sources In U.S. Homes n The movement of soil gas into a home is the predominant entry route. n These are averages - a particular home can be different! Water < 1% Soil Gas % Diffusion 1 - 4% Emanation 2 - 5% Radium Containing Soil

Radon Gas Spatial Distribution Radon enters from beneath foundation and travels upward. ◦ Diluted with outdoor air infiltrating building 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. 10 < 5 5-6

Radon sources SourcesCuries Per Year Emanation: Soil2,000,000,000 Ground Water500,000,000 Emanation: Oceans30,000,000 Phosphate Residues3,000,000 Uranium Tailings Piles2,000,000 Coal Residues20,000 Natural Gas10,000 Coal Combustion900 Human Exhalation10

Why are we concerned about radon? Radon is a known carcinogen, in the highest ranking category with tobacco products U.S. SURGEON GENERAL HEALTH ADVISORY “Indoor radon is the second-leading cause of lung cancer in the United States and breathing it over prolonged periods can present a significant health risk to families all over the country. It’s important to know that this threat is completely preventable. Radon can be detected with a simple test and fixed through well-established venting techniques.” – January 2005

Why Is Radon A Concern? Radon decays into radioactive particles known as radon decay products. These particles are easily inhaled and deposited in the lungs where they can damage sensitive lung tissue. Radon Decay Products Radon Radon

What happens when radon is inhaled?

Alpha  Decay 4 He Nucleus Ejected from 222 Rn Nucleus +2 He + Po 4 He Po Radon - 222

What Happens When Radon Decay Products Are Inhaled? n Highly radioactive particles adhere to lung tissue, where they can irradiate sensitive cells. n Radiation can alter the cells, increasing the potential for cancer. Double Strand Breaks

Radon Progeny 218 Po and 214 Po deliver the radiologically significant dose to the respiratory epithelium. Lead-210 Polonium-214 Bismuth-214 Lead-214 Polonium-218 Radon-222      Lead-206 Polonium-210 Bismuth-210    22 yrs 4 day 3 min 27 min 20 min 0.2 ms 5 day 138 day Stable

EPA & Surgeon General Recommend Take action if a home is at or above 4.0 pCi/L (year long average) 4.0 pCi/L EPA ACTION LEVEL Average indoor: 1.3 – 1.4 pCi/L Average outdoor: 0.4 pCi/L

Testing for Radon Initial short-term test (2-7 days) ◦ Closed house conditions One testing device Place in lowest lived in part of house, ideally bedroom, living room and most frequently occupied rooms Not a closet, bathroom, kitchen, storeroom, garage, crawlspace, attic. Follow-up test if results are ≥ 4 pCi/L

Purpose of Test Determines Location Lowest lived in Lowest suitable for Occupancy w/o Renovation NO YES Test in livable room. Keep away from drafts and moisture.

Radon Measurement Devices Activated charcoal device Electret Ion Chamber Continuous Radon Monitor

Activated Charcoal Devices Measures radon Used by professionals and homeowners Different devices have different optimal deployment periods. Requires no power to operate. In small container (paper, metal or plastic) containing activated charcoal. Can only be read in the lab, not in the field.

Activated Charcoal Device Examples For short-term tests Must be analyzed within 6 days

Activated Charcoal Devices AdvantagesDisadvantages Compact, convenient and economical Can be used for 48-hour test Can be easily mailed to lab for analysis Passive, does not require power and silent Quick and accurate analysis Limited to short-term sampling If radon peaks and valleys are dramatic, the results validity is questioned because of a possible bias over the last 12 hours. Provides no indication of changes in radon during measurement. Tampering detection difficult.

Electret Ion Chamber (E-Perm) Short-term and long-term measurements 2 days-1 year, dependent upon: ◦ Configuration ◦ Type of disk used ◦ Anticipated radon concentration

Measuring Electret Voltages Electrets are pre-charged by manufacturer. Electret voltages are measured before and after deployment. Reported radon is a function of:  Voltage drop (Approximate 2 volts drop per day per pCi/L)

Electret Ion Chambers AdvantagesDisadvantages Short-term and long-term measurements Electret can be re-used until voltage falls below the desired operating voltage for the device used (200 volts) Can be recharged by manufacturer ($30) Sensitive to external gamma radiation. Correction needed. Sensitive to altitude changes. Correction needed. Can be damaged by touching surface, surface contamination or impact. Pre/post voltages must be measured at the same temperature.

Continuous Radon Monitors Sun Nuclear (Solid State Silicon Detector) ◦ Impacts from alpha particles are counted. ◦ Data plotted and averaged ◦ Relatively low efficiency ◦ Provides continuous measurements ◦ Used for diagnostics

Continuous Radon Monitors AdvantagesDisadvantages Exposure variable: 48 hrs to many months Relatively good precision Can track hourly variations Options to down load or print on site Can indicate tampering or ventilation. Higher priced Requires trained operator Annual calibration Bi-annual performance tests. Can only test one room at a time.

Results from a CRM

Do It Yourself Test Kits

Radon Mitigation Training

Twa-le Abrahamson-Swan (509) April 8, 2014 at the US House Appropriations Committee – testifying on cuts to radon funding and services for Tribes and Environmental Justice Communities. AP06-Wstate-Abrahamson-SwanT pdf AP06-Wstate-Abrahamson-SwanT pdf