Information to Help Understand Radon Testing
More and more, informed buyers are having radon tests performed when considering the purchase of a home.
The Facts about Radon Testing
Finding elevated concentrations of radon doesn’t mean you should walk away from your dream home!
Radon reduction technology has improved so much over the last few years that reducing radon is easy and affordable.
Section 4.4 of the Canadian Environmental Law Association’s Review, as it refers to Real Estate Transactions – Seller’s Property Disclosure Form specifically asks “if there is a known radon problem”. If it is known by the seller to exist or ever have existed, it must be disclosed. This would be true even if previous test results were less than Health Canada’s action limit of 200 Bq/m3. In all cases, sellers should provide copies of any radon test results. If a radon mitigation system exists, it also must be disclosed, as it is presumed that radon had existed previously and that if the system were to fail, the radon level would return to its original level.
If radon concerns are discovered during the inspection process, understand that they can be remedied through mitigation and that normal real estate negotiation techniques can be used to resolve the costs associated with radon reduction.
How to approach Radon Testing when searching for a new home?
Radon testing is simple. Here is a common approach:
- Find the house you want to buy.
- As part of the home inspection process, request a short-term (2-7) radon test, using a qualified radon measurement professional. The Canadian National Radon Proficiency Program (CNRPP) is the only organization recognized by Health Canada to conduct Radon Measurement, Mitigation, and Analysis. Your home inspector may or may not be qualified to conduct radon testing.
- If the short-term test result is less than 200 Bq/m3, Health Canada would not recommend any follow-up action, although there still is some risk at exposures less than 200 Bq/m3.
- If the short-term test result is 200 Bq/m3 or higher, then consider asking the seller to pay for a mitigation system, or consider purchasing the home and performing a long-term test to determine what the actual exposure is. There are some Realtors who will negotiate the cost between the parties and place monies in escrow. Once the long term test is completed the results are provided and escrow is released or returned.
- Once you decide to reduce the radon in the house, seek bids from qualified contractors who are willing to guarantee and warranty results. Review the CNRPP website to find qualified professionals in your area.
- Use bids from contractors as a basis for negotiations with the seller.
- If the seller is willing to pay for a mitigation system, work with your realtor to determine the best way to obtain the funding from the seller and have the system installed after taking possession of the property.
Remember All homes can be fixed!
First, it is strongly recommended that you use a qualified radon measurement professional who has been trained in the proper placement of radon measurement devices and the interpretation of their results. A list of certified individuals can be obtained from the Canadian Nation Radon Proficiency Programs website at www.cnrpp.ca.
Here are some tips for testing and for reducing radon:
- Radon tests are to be placed in livable areas — not crawlspaces or attics.
- Radon tests are to be placed no closer than 20 inches to the floor, and no closer than three feet from openings in exterior walls, such as windows and doors.
- Collecting data for less than 48 hours is not valid for determining the need to mitigate, or reduce, radon in a home.
- When doing a short-term test, all exterior doors and windows are to be closed (other than normal exit and entry) and the device is to be placed in the lowest level of the home.
- If the radon measurement professional performs two short-term tests at the same location and under the same conditions, the results should be averaged. It is not acceptable to continue to test until a preferred result is obtained.
- Radon test results obtained from different parts of the home are NOT averaged.
- During short-term tests, evaporative coolers (swamp coolers) and other devices that exchange considerable air to the outside should be shut off.
- Continuous monitors often are used to detect occupant tampering of test conditions.
- If a continuous monitor (which measures radon hourly) is used, the average of the measurements is used, rather than the highest reading observed.
- Radon levels vary from season to season and long-term tests are the preferred method for determining health risk.
- When doing a long-term test of more than 90 days, no special conditions are required for exterior doors and windows, and the device typically is placed in the lowest level of a home that is frequently occupied.
- Only one room on the selected level of the home needs to be tested.
- Test devices should not be placed in locations with temperature differences of ±10o F from room temperature, on hot surfaces or in areas of elevated humidity.
Radon is an invisible, radioactive gas created from natural deposits of uranium and radium in the soil.
Radon is an invisible, radioactive gas created from natural deposits of uranium and radium in the soil. Radon gas can be drawn into a building and accumulate to concentrations that can increase the potential for contracting lung cancer.
Although there are rare cases where the source of the radon has come from building materials created from spent-uranium processing plants, the major source of radon in New Brunswick homes comes from the natural deposits of uranium commonly found in New Brunswick’s geology. It is seldom caused by human intervention like other environmental concerns.
Radon enters a building through its foundation – the basement, crawlspace, or slab. As the radon moves up in the building, it is diluted with air that leaks through exterior walls and Radon concentrations openings from the outside air.
At the time of resale, it often is desirable to know what the potential radon exposures could be, independent of how a person operates or lives in a building. Radon enters a building through its foundation – the basement, crawlspace, or slab. As the radon moves up in the building, it is diluted with air that leaks through exterior walls and Radon concentrations openings from the outside air.
Consequently, radon levels typically are the highest in the lowest portion of the home suitable for occupancy. typically are the highest in the lowest occupiable portion of a home If a test is conducted in the lowest level of the home with all the exterior doors and windows closed, one would be able to say with reasonable assurance that the exposures in upper levels of the home are less than the reading obtained in lower levels. It also can be assumed the exposure would be less when fresh outdoor air is allowed into the home. Short-term tests typically are conducted over a two- to three-day period, and the results represent the radon potential of the home.
Of all of the problems a house may have, radon is one of the easiest to identify and fix!
HOW DO I TREAT RADON
Considerable research conducted by government agencies, educational institutions and private industry in Canada and provinces forms a very strong foundation for properly mitigating radon in homes, schools and commercial buildings. The techniques are straightforward, reliable and typically can be done in one day by a qualified contractor.
However, simple radon reduction requires more than trying to seal openings in the foundation. In fact, caulking and sealing of foundation openings, on its own, has proven NOT to be a suitable technique.
Radon is mitigated by installing a system that will draw the radon-laden soil gas from beneath the foundation and exhaust it outside of the building, far enough away from windows and other openings that it will not re-enter.
A reduction system typically consists of a plastic pipe connected to the soil either through a hole in a slab, via a sump lid connection or access beneath a plastic sheet in a crawl space. Attached to the pipe is a quiet, continuously operating fan that discharges the radon outdoors.
How this is done is a function of the construction of the home, rather than the radon concentrations that exist. A home with more than one foundation can present challenges to collecting the soil gas from under all portions of the building. However, talented mitigation contractors typically can connect multiple systems together so that only one fan system is required.
Crawlspace foundations can be more costly since the contractor needs to install a high-density plastic sheet over the soil, seal it to the walls and then route the piping to the fan. However, the added benefit of reducing moisture in the crawlspace, in addition to reducing radon, can be a real plus.
- Average installation cost: $1,500
- Average operating cost: $3/month
- Expected life span of fan: 11-15 years
- Fan replacement cost: $145-300
- Periodic maintenance: none
Always ask your builder about radon-resistant features. Always test the home to be sure it reduces the radon to levels.