Canadian Association of Radon Scientists and Technologists

Helping Canadians Reduce Radon Risk

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Are you a Real Estate Agent looking to learn more about RADON?  

Here are some BASIC RADON FACTS...



Testing for RADON is EASY and it should be done in the living area of the home.


Testing for RADON should be done for at least 91 days.    


RADON enters buildings where they touch the ground. 

Every house can be reduced to a lower radon level.

Call a professional to help: 

www.c-nrpp.ca/find-a-professional




Every home needs to be tested for RADON and all homes can be fixed.


 

RADON kills 3200 Canadians per year from lung cancer.

RADON is the leading cause of lung cancer in non-smokers.



The cost of a RADON MITIGATION system is NOT expensive.

It is less costly than other home renovations.

Get a certificate in the Radon and Real Estate Course - register online here

The Real Estate Agent is Key

As radon awareness across Canada grows, you may find that an increasing number of homeowners are starting to ask about radon, and more homes will have some type of radon system installed.  The best way for you to help your clients is to be informed about radon so that you can answer their questions knowledgeably and know where to direct them for additional information and support.


Every home can be fixed

The most important message for you as a real estate agent to convey, is that your clients can go ahead and fall in love with their dream home!  No matter what the radon levels, once they move in and test the home, there is a way to effectively reduce high radon levels in every home.

What is radon:

Radon is a radioactive gas.  It starts in the ground as uranium (a solid mineral), then becomes radium (still a solid), and finally radon (a gas).  As a gas, radon moves through the ground and up to the surface. 

When radon filters out into the outside air, it dilutes to levels that are not a health concern.

When radon enters our homes, it can build up to dangerously high levels, which is why we need to test indoor spaces.

Being exposed to high levels of radon gas today makes us more likely to develop lung cancer in years to come.


Testing for Radon:

A C-NRPP Professional is a reliable third-party to provide an accurate radon measurement.  Any of the following test methods, when performed by a C-NRPP Professional using the certified guidelines, will give accurate results for the time period being tested. 

Long-Term Radon Measurement – is a radon test of longer than 90 days

Radon levels can vary day to day and hour by hour.  We recommend basing a decision for mitigation on a radon test that will most accurately predict an occupant’s annual exposure level.  Health Canada and C-NRPP recommend basing a decision to mitigate on a long-term radon measurement during the heating season while the home is occupied.

Real Estate Screening Assessment - is a radon assessment of at least 4 days and up to 7 days.

Short-Term Radon Measurement –is a radon test of less than 90 days

Short term measurements should always be part of a two-step process of short-term and long-term follow up measurement.  C-NRPP and Health Canada strongly recommend that any and all short-term radon measurements be followed up with a long-term radon measurement.

NOTE: A test that is less then 48 hours is NEVER acceptable as a radon test.  There are some non-certified companies who are conducting 1 hour testing and this is not acceptable. 


Certified Testing vs. Non-certified Testing

When hiring a professional to test for radon, make sure they're C-NRPP certified.   A list of certified professionals is available at www.c-nrpp.ca, and can be searched by province or postal code to find a professional near you.  Certified professionals will use professional-grade C-NRPP-approved radon measurement devices and are trained to place and use them properly.  

If a home tests high for radon, it can be fixed.  It’s important to consult a C-NRPP Professional (www.c-nrpp.ca/find-a-professional) who will design a radon mitigation system specific to the home.  

With a properly installed Radon Mitigation System, even homes with radon levels of 5,000 Bq/m3 or above can be reduced below the Canadian Guideline level of 200 Bq/m3.  Radon mitigation is a proven technique, and the cost to install is less than most home renovations.  It’s a one-time expense with minimal ongoing operating costs.  Each home is unique, so your best option is always to get a quote from a C-NRPP professional on the cost of installation.


How does RADON affect our health?

Radon is radioactive which means that radon spontaneously decays and releases energy.  Since it is a gas, radon is inhaled into our lungs, and the energy released damages the DNA of the cells of our lung linings.  As the cells repair themselves, mutations can occur and result in lung cancer.

In Canada the statistics show that radon is responsible for over 3000 lung cancer deaths per year.

Reducing Radon Levels:

Radon Mitigation System

When installed by a C-NRPP professional, a radon mitigation system is the most effective way to reduce radon levels in a home.  There are various types of systems with different names, but they all have the same purpose:

A radon mitigation system provides a pathway for the gas to reach the outdoor air without entering the home.

Using a fan, a radon mitigation system creates an active pathway for radon - as well as moisture and other soil gases - to move directly from beneath the slab of the house to the outdoor air without entering the building.



RESEARCH:

Health Canada has conducted research to confirm that a radon mitigation system is the most effective method of reducing radon levels.

HIRING a certified professional LOWERS RADON BY UP TO 90%

INCREASING home ventilation LOWERS RADON BY UP TO 25-50%

SEALING cracks LOWERS RADON BY AN AVERAGE OF 13%

Find online at: https://www.canada.ca/en/health-canada/services/publications/health-risks-safety/residential-radon-mitigation-actions-follow-up-study.html


Know who to Trust for Information:

C-NRPP is Canada’s national certification program for Radon Professionals

Health Canada and CARST (the Canadian Association of Radon Scientists & Technologists) developed the Canadian National Radon Proficiency Program (C-NRPP) to provide building owners with trained and certified professionals to help with testing and reducing radon levels.

To find a certified professional, click: www.c-nrpp.ca/find-a-professional

Radon Measurement Professionals measure radon levels in buildings.

Radon Mitigation Professionals install mitigation systems to reduce radon inside buildings.

A certified professional is your best resource when it comes to radon-related questions!


Health Canada:

Health Canada has regional radiation specialists across Canada.  You can find their contact information on their website:

https://www.canada.ca/en/health-canada/corporate/contact-us/radon.html







What are the options for Purchasers?

When purchasing a home, it's important to remember that every home can be fixed.  The new owners can be confident that they can move in, test for radon, and mitigate if required.  When considering the budget for home purchase and initial renovations, it's best to add radon testing and mitigation (if necessary) to the top of the spending priority list.

To know how much to reserve for a potential mitigation system, contact a certified professional to get an estimate. 

There may be some circumstances under which purchasers may want some indication of what radon levels are likely to be.  For these circumstances, CARST has developed the Radon Screening Assessment.

Another Option? – Radon Screening Assessment

In certain circumstances, home buyers may want an indication of what radon levels are likely to be in the home they are considering purchasing.  Due to the time constraints frequently experienced during a real estate transaction, long-term radon measurements are often not practical during the time a house is for sale.  If a long-term radon measurement has not been conducted within the 2 years prior to a house being listed, a Radon Screening Assessment can provide an indicator on whether funds may be required to cover the installation of a radon mitigation system.  It’s important to remember that even after a home has been assessed using a radon screening assessment, it must still be tested using a long-term radon test once the new owners take possession of the house. 

Specific protocols have been developed for conducting a Radon Screening Assessment.  You can contact a C-NRPP professional to discuss or read through them online here.


Understanding how a Radon Assessment fits into a Real Estate Transaction

Here's how an assessment during a real-estate transaction works:

First, contact a C-NRPP Measurement Professional to conduct a Radon Screening Assessment.

The occupant of the home must agree to the test, and also to keeping the home under 'closed house' conditions for as long as required.

Closed-house conditions include: 

      • Windows should stay closed at all times, 
      • External doors opened only for entry and exit,
      • Attached garage doors should be opened only for entry and exit,
      • Fireplaces should not be operated during the radon test, unless they are the primary heat source.
      • Clothes dryer, range hood, and bathroom fan operation should be limited to the minimum necessary,
      • Radon mitigation systems shall be operated as normal.
      • Heat-Recovery Ventilator (HRV) and Energy Recovery Ventilator (ERV) shall be left to operate (or not operate) as found.  For example, if an HRV is plugged in and working it should be left working, if unplugged, should be left unplugged.
The Radon Screening Assessment will be set up by the C-NRPP Measurement Professional.  The detector must be in place for a minimum of 4 days.  A longer duration is preferred, but not always practical in a real estate situation.   The C-NRPP Measurement Professional has specific guidelines about where and how to place the test, as well as how to report on the results.


Understanding the Radon Assessment Report

The Radon Assessment Report will provide a result of Green, Yellow or Red to help you understand the likelihood that the annual average radon concentration could be above 200 Bq/m3.     

Red Test Result

A Red Test Result indicates a radon screening assessment of greater than 400 Bq/m3. This result indicates a strong likelihood that the annual average radon concentration is above 200 Bq/m3.

Yellow Test Result

A Yellow Test Result indicates a radon screening assessment of greater than 75 Bq/m3 during the heating season or 50 Bq/m3 outside the heating season, up to and including 400 Bq/m3.  This result indicates that there is a higher likelihood that the annual average radon concentration is above 200 Bq/m3. 

Green Test Result

A Green Test Result indicates a radon screening assessment of 75 Bq/m3 or less during the heating season and 50 Bq/m3 or less outside the heating season.   It is important to note that a “Green” test does not guarantee that the annual average radon concentration in the dwelling is below 200 Bq/m3. A long-term follow-up radon measurement conducted during the next heating season must still be carried out.

Radon Research from University of Calgary

Research was conducted by a group of researchers out of the University of Calgary.  The research covered many aspects, but among on aspect was short-term versus long-term radon test comparison.  The research stated, "The 5 day tests predicted 90 + day counterparts 80% of the time (r2 = 0.805)  " and "Short term test precision displayed progressively decreasing the further into warmer temperature months that short term tests took place. To interrogate this further, we isolated 100 pairs of 90 + and 5 day tests showing strong agreement (r2 = 0.909) in winter (March) and performed another 5 day test in the identical location in summer (July-August), finding r2 = 0.011 for a 5 day summer test versus a winter 90 + day test, or r2 = 0.035."

This latest research correlates well with the research on which CARST based our Real-Estate Assessment Guideline. The new research helps to emphasize the importance of clear communication regarding the limitations of the assessment test, and the importance of always following-up an assessment test with a long-term test during the heating season as specified in the guideline.

Historically, Health Canada, CARST and other bodies have recommended conducting long-term testing (minimum 91 days)  this recommendation is based on historical research which shows that radon levels can fluctuate and because radon is a long-term exposure concern it is best to understand a person exposure over a duration of time.  Long-term tests of 91 days or more for basing a decision to mitigate continue to be our recommendation.  However, there are times when a short-term radon test can be useful  The duration of the short-term test should be determined by the purpose of the results of the test.  A short-term test should never be shorter that 48 hours and it would be best to test for a minimum of 7 days. the longer the duration of the test, the more representative of the average annual radon concentration.  

It is important to remember that CARST continues to emphasize the importance of long-term testing. The Real-Estate Assessment Guideline was developed to provide structure to those wishing to include a radon test as part of a real-estate transaction; a situation that is becoming increasingly common.

What radon prevention measures are in place in new homes?

New homes with radon prevention measures still can have high levels of radon.  Some new homes feature radon resistant features, but these do not guarantee low levels. Testing is ALWAYS recommended when occupying a new space. 

In most provinces across Canada, the building code states that new homes must have a radon rough-in system. What do homeowners need to know? First off, the radon rough-in does not reduce radon; it’s simply the beginning of a system. The rough-in is included in new construction to make it easier and more cost effective to install a radon mitigation system should one be required. Secondly, the rough-in must be properly capped, sealed and labeled, otherwise it could be introducing radon into the house.

Homeowners need to test their home for radon and then decide if the radon rough-in needs to be finished into a Radon Mitigation System.

The National Building Code states:

  • A home must have a radon barrier
  • A home must have a layer of gravel beneath the radon barrier (this provides air movement for an eventual radon mitigation system)
  • A home must have a radon rough-in stub pipe that connects under the concrete floor slab to the middle of the house. The stub pipe that sticks up from the slab doesn’t have to be located in the middle of the basement; it can have pipe under the concrete slab which leads to the middle. Ideally this rough-in will be located in a maintenance room or furnace room so that a finished pipe and fan can be added to complete into a radon mitigation system if required.
  • A radon rough-in stub pipe must be properly labeled.

REGIONAL DIFFERENCES:

Most provinces adopt the National Building Code.

The differences are:

  • Ontario has only adopted it in various municipalities.
  • Quebec has not adopted the radon control measures.
  • British Columbia has added an extension so that the rough-in pipe extends outside the building.

NOTE FOR BC: The building code in BC is divided into two approaches.  It either has NO radon rough-in or it requires an extended radon rough-in which means the pipe extends to exit the building.  This requirement is listed in a table in the building code entitled Table C-4.

NOTE FOR Ontario:   If you’re working in Ontario, it’s essential to inform homeowners about Tarion’s Home Warranty radon coverage. If a long-term radon test indicates that radon levels within a home exceed Health Canada’s actionable level of 200 Bq/m3, then Tarion will cover the costs required to mitigate a home up to a limit of $50,000.   Find more information here.


Tarion Warranty - Protects Ontarians from Radon

If you’re working in Ontario, it’s essential to inform homeowners about Tarion’s Home Warranty radon coverage. If a long-term radon test indicates that radon levels within a home exceed Health Canada’s actionable level of 200 Bq/m3, then Tarion will cover the costs required to mitigate a home up to a limit of $50,000.

Find more information on Tarion's website here.  


Frequently Asked Questions:

Q.  Health Canada suggests testing for at least 3 months.  Why does this document suggest a 4 day test?

A. Every home needs to be tested for radon using a long-term (3 months+) test.  This guideline offers an additional test that can be performed during a real-estate transaction, in the case where the home had not already been tested for radon prior to being listed for sale. 

Due to the time constraints frequently experienced during a real estate transaction, long-term radon measurements are often not practical during the time a house is for sale.  If a long-term radon measurement has not been conducted prior to a real estate transaction, a radon screening assessment can provide important information on whether funds may be required to cover the installation of a radon mitigation system.  It’s important to remember that even after a home has been assessed using a radon screening assessment, it must still be tested using a long-term radon test once the new owners take possession of the house.


Q.  We’ve lived in our home for many years.  Why should we test our home now, when we’re selling it?

A. Radon is a health hazard that Canadians have become increasingly aware of over the past few decades.  Every home needs to be tested for radon, as it’s the only way to know the radon level in the home and whether the level should be reduced.  Just as the home inspection will let the prospective buyer know about upcoming expenses, the radon screening assessment will let them know whether they’re likely to have the expense of installing a radon mitigation system.  It is important to budget funds to take care of such an important health concern. 


Q. Will the radon assessment test slow the sale of our home or ruin the transaction?

A. More and more Canadians are including a radon test as part of buying a home.  In some areas every home is tested for radon prior to being sold.  CARST’s Guideline sets out the best way to include radon in the real-estate transaction while considering everyone involved.  Just like an old furnace or roof shingles in need of repair, high radon levels are easily remedied, at a price point that can be included in the negotiations.  Following this guideline means that everyone involved in the sale of your home is “on the same page” and misunderstandings are less likely to occur.


Q. How much does a radon mitigation cost?

A. The cost of radon mitigation varies depending on the type of house construction, the type of mitigation system required, the location of the home, and market trends.  It is difficult for a non-professional to assess the various factors that will determine how difficult it is to mitigate a given home.  It is therefore important to obtain a quote from a C-NRPP mitigation professional when budgeting for the cost of mitigation.  While the majority of mitigations across Canada range in price from $3 000 to $4 000, the cost may occasionally be as high as $10 000. 

Find more information here: https://takeactiononradon.ca/radon-reduction-sweepstakes-report-2020-2021/ 


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