Managing Radon in Buildings A Canadian Perspective SCOTT CRYER, P.GEO. MARCH 28, 2017 PINCHIN ALL RIGHT RESERVED SEMINAR OUTLINE What is Radon? Health Concerns Acceptable levels Radon in buildings Guidance/potential & existing regulations Testing for Radon Mitigation of Radon Radon in new construction WHAT IS RADON? Naturally occurring radioactive gas Comes from the breakdown of Uranium in soils, rocks, groundwater Colorless, Odorless, and Tasteless 1
HEALTH CONCERNS Group A Carcinogen 16% of all lung cancer deaths Main cause of lung cancer in nonsmokers 3,200 lung cancer deaths are attributed to radon in Canada every year (21,000 in America) HEATH CONCERNS RADON DECAY PRODUCTS Radon gas breaks down and releases radon decay products (RDPs) RDPs attach to lung tissue RDPs breakdown, releasing alpha & beta particles Alpha particles can kill lung cells or cause damage/mutations which can lead to lung cancer Human skin is thick enough not to be affected CLOUD CHAMBER It allows you to see alpha and beta particles 2
CLOUD CHAMBER GEOLOGIC RADON POTENTIAL MAP HEALTH CANADA RADON TESTING 14,000 homes across Canada ~ 7% of homes have radon concentrations above the guideline (200 Bq/m³) ~ 7% of US homes are above the guideline of 4 pci/l 3
Province/ Territory HEALTH CANADA RADON DATA % Below 200 Bq/m² % 200 to 600 Bq/m² % Above 600 Bq/m² Alberta 93.4 6.0 0.6 6.6 British Columbia 92.1 6.7 1.2 7.9 Manitoba 76.3 21.1 2.6 23.7 New Brunswick 75.2 18.7 6.1 24.8 Newfoundland & 94.1 4.6 1.3 5.9 Labrador Nova Scotia 91.2 6.3 2.5 8.8 Northwest 94.6 4.9 0.5 5.4 Territories Nunavut 100.00 0.0 0.0 0.0 Ontario 91.8 7.3 0.9 8.2 Prince Edward 96.5 3.5 0.0 3.5 Island Quebec 89.9 9.0 1.1 10.1 Saskatchewan 83.7 15.3 1.0 16.3 Yukon 80.4 13.8 5.8 19.6 % Above 200 Bq/m² US EPA RADON DATA RADON LEVELS IN BUILDINGS Some known hotspots with increased potential for elevated radon levels. Radon levels can vary greatly between adjacent buildings The ONLY! way to know what the radon levels are in a building is to test??? 4
RADON ENTRY POINTS CRAWLSPACES Large soil surface were suction from building is applied Crawlspace vents are little help Floor insulation above is not a radon barrier RADON AND BUILDING TYPE 5
FORCES THAT DRIVE RADON INTO A BUILDING Buildings can create vacuums that radon draw in (convective flow/stack effect). Natural causes; thermal stack effect, wind, rain, frost Mechanical causes; exhaust fans, windows, fireplaces, etc. RADON ACTION LEVELS CANADA Health Canada action level = 200 Becquerels per cubic metre (Bq/m3) which is a measurement of RADIATION Naturally Occurring Radioactive materials (NORM) action level = 200 Bq/m³ RADON ACTION LEVELS UNITED STATES EPA Action Level = 4 pci/l (equal to 148 Bq/m³) GLOBALLY World Health Organization (WHO) recommends 100 Bq/m3 6
CANADIAN LEGISLATION Canada Labour Code Occupational exposure limit currently at 800 Bq/m³ Will be harmonized with Health Canada s action level of 200 Bq/m³ in the Winter of 2017. Will affect many industries such as telecommunications companies, banks, shipping companies, fisheries etc. General Duty Clause in each province US LEGISLATION Quite variable from state to state Legislation in the US generally includes the following: Certification Programs Real Estate Public Schools New Construction Residential rental HEALTH CANADA MEASUREMENT GUIDELINES Recommends testing during the heating season Does not recommend short-term testing Action level of 200 Bq/m (148 pci/l) 7
ANSI/AARST MEASUREMENT STANDARDS Short-term and long-term testing is permitted Testing occurs on ground contact and upper floors except homes (just lower occupied levels) Advise there is no safe level and reference World Health Organization HEALTH CANADA MITIGATION GUIDELINE Time Frame to Remediate (no specific time frame in US) Radon Concentration Recommended Remedial Action Time > 600 Bq/m 3 In less than 1 year 200 600 Bq/m 3 In less than 2 years < 200 Bq/m 3 No action required RADON VARIABILITY IN BUILDINGS 8
RADON VARIABILITY IN BUILDINGS SHORT-TERM TESTING Not recognized as a basis for mitigation by Health Canada Commonly used for mitigation decisions in the US Usually for ~ 2 7 days Closed house conditions Used for real estate transactions Provides an indication (snapshot) of radon potential Follow-up with long-term testing CONTINUOUS RADON MONITORS CONTINUOUS RADON MONITORS Radon results calculated at hourly intervals Lock-out/tamper resistant Used for diagnostic testing with mitigation work 9
CONTINUOUS RADON MONITORS LONG-TERM TESTING Recommended by Health Canada and as an option in the US 91 days to 1 year Under normal living conditions doesn t inconvenience anyone HEALTH CANADA MITIGATION GUIDELINE (2010) Covers virtually all mitigation techniques 10
ANSI/AARST MITIGATION STANDARD (2015) Similar to the Canadian guidance SUB-SLAB DEPRESSURIZATION Suction created in a pit under the slab Radon collected and exhausted outdoors Runs 24/7 Highly effective SUB-MEMBRANE DEPRESSURIZATION Suction created under a membrane placed over exposed soil or rock 11
MODIFICATION OF AIR HANDLING SYSTEMS HVAC can dilute radon levels and pressurize buildings to keep radon out Systems must be balanced HRV/ERVs requires regular maintenance to be effective typically lower radon by ~25-50% HRV/ERVs have ongoing energy penalties REMOVAL OF RADON FROM WELL WATER Aeration water goes into a tank and is aerated. Radon is stripped and exhausted outside. Carbon Adsorption Radon adsorbed onto activated carbon filter which is disposed of. Gamma radiation buildup in the carbon filter. TESTING AFTER RADON MITIGATION Follow-up sampling to ensure concentrations have decreased Long-term retest within 2 years and every 5 years after that (every 2 years in US) Test when major renovation occurs Occupancy changes may require further testing 12
RADON RESISTANT CONSTRUCTION TECHNIQUES Passive systems (vs. active) In conjunction with various measures e.g. caulking and sealing joints/openings, seal sump pits, granular fill and soil gas membrane Addressed in Building Codes New standards in US for homes & large buildings New standards in Canada being finalized CERTIFICATION Health Canada recognizes the Canadian National Radon Proficiency Program (C-NRPP) C-NRPP is a certification program designed to establish guidelines for training professionals in radon services www.c-nrpp.ca CANADIAN ASSOCIATION OF RADON SCIENTISTS & TECHNOLOGISTS (CARST) A Canadian association dedicated to: Ensuring quality standards are developed Educate Canadians on identifying and managing radon in dwellings and workplaces Provide a bridge between radon professionals and public and private organizations www.carst.ca 13
CERTIFICATION Recognized by the US EPA AARST-NRPP professionals use ANSI Standards and best practices for radon measurement and mitigation Leads the radon community in scientific inquiry, communication, and radon risk reduction. http://aarst-nrpp.com/wp/ MOVING FORWARD Develop a testing program for your building Mitigate high radon levels as required Ensure testing and mitigation is completed by a C-NRPP or NRPP certified professional Test your home too! QUESTIONS? For more information or for newsletters, please visit www.pinchin.com Email : scryer@pinchin.com Toll Free: 1.888.767.3330 Direct Line (905) 363.1311 14