Radon Mitigation

According to surveys conducted by the World Health Organization, the United States currently has studies on the impact codes and thus lead to passive systems which reduce the Radon levels by 50%. The United States also has a system in place to ensure that new buildings being built have Radon concentrations determined; Canada, on the other hand, does not.


For pre-existing buildings, the urgency of mitigation is determined by the concentration of the Radon. While measuring mitigation efforts, the cost effectiveness must be taken into account and newly mitigated houses should be retested after a period time to ensure mitigation efforts are still performing.
If a home demonstrates Radon levels higher than 200 Bq/m3, action should be taken to remediate the problem.

Possible options for homeowners are:

- The most common is active soil depressurization, which is the process of placing subslab suction on the porous subslab fill, the groundwater control components as well as the perforated sump. While dealing with an existing structure, issues may occur due to the difficulty of sealing the space between the soil and the existing building. Subslab depressurization costs $800 to $2,500, with passive subslab depressurization costing $550 to $2,550.
- A second mitigation technique, though less common, is used to treat incoming water when it is a source that releases Radon into the dwelling. Aeration is used to bubble air in a sealed tank, effectively transferring the Radon from the water to the outside. Filtration with granular carbon is also used; however is less effective at removing Radon. Aeration processes cost $3,000 to $4,500 and granular carbon systems cost approximately $1,000 to $3,000.
- With regards to crawl spaces, a high density polyethylene sheet is laid on the ground with the seams sealed to the foundation. A perforated pipe is placed beneath the plastic along with a fan, this creates a vacuum which causes the Radon to be transferred to a location outside the house.
- Increase the mechanical ventilation, via a heat recovery ventilator (HRV), to allow an exchange of air.
- Seal all cracks and openings in foundation walls and floors, and around pipes and drains.
- Paint basement floors and foundation walls with two coats of paint and a sealant.
- Renovate existing basement floors, particularly earth floors.
Contractors who perform mitigation in the valley, and are accredited by the National Environmental Health Association are:

Conestoga Rovers and Associates
www.CRAworld.com
902-468-1248

Radon Atlantic Consultants Ltd
www.RadonAtlantic.com
902-444-8724

SLR Consulting Ltd
www.slrconsulting.com
902-420-0040

Health Canada recommends contractors be certified from an accredited organization; such as the National Environmental Health Association or the National Radon Safety Board.