Houses
with elevated radon concentrations are EASILY and inexpensively fixed by a
qualified contractor.
Although, the cost may vary depending on the size and design of the home, it
seldom runs more than $800 to $2,000.
Radon
mitigation really works permanently reducing concentrations by up to 99%. And
since most systems completely prevent soil air from entering the house, you may
notice other air quality improvement as well.
Radon
reduction measures in no way diminish the dollar value of the home and are
accepted nationally as home improvement. Very little maintenance is required and
system operation costs are generally less than $10 per month for the fan
electricity and very minor loss of conditioned air.
Finally,
since reduction systems lower radon concentrations so effectively and eliminate
peak fluctuations, living in a mitigated home reduces one’s risk of radon
related lung cancer to as low as
reasonably achievable
(ALARA), - even lower than living in most houses testing below the EPA Action
Level with no radon control system.
For
more information, please refer to the EPA’s Home
Buyer’s & Seller’s Guide to Radon Reduction and Consumer’s
Guide to Radon Reduction. To receive your copies, call the EPA’s Policy
& Public Information Branch at (202) 233-9400 or on the World Wide Web by
clicking on the names.
Your
state radon office in North Carolina is at (919) 571-4141. Consumer Federation
of America’s toll free Radon Fix-It Line is for consumers whose results are
4Ci/l or higher. Call (800)
644-6999 weekdays between noon and 8 pm EST for live operators.
What is Radon?
Radon
is an odorless, colorless radioactive gas which is formed by the natural
breakdown of uranium. Radon can be found in high concentrations in soils and
rocks containing granite, shale, phosphate and uranium, or occasionally
industrial waste, in almost any area. As it is produced, it moves through the
soil to the earth’s surface where it can either safely dissipate in outdoor
air or seep into a building through cracks and gaps in its foundation or slab.
It can also be introduced into the air within a building through the water
supply, particularly from well systems, or from certain building materials.
Research
has shown that once trapped inside a closed structure, radon can accumulate to
the point where a potential health hazard may exist. Actually it is the
breakdown of radon into what is referred to as radon decay products (or radon
daughters) that represents the greatest concern. These decay products become
attached to airborne particles which can be inhaled and ultimately cause lung
tissue damage.
The
concentration of radon in any particular structure is dependent on a number of
variable factors such as soil composition, building construction, weather
conditions, and even occupant lifestyle. Levels may vary from day to day, season
to season. Consequently, it is difficult to readily determine average annual
radon levels in particular building. The
greatest potential for high radon concentrations exists when the air pressure
within a house is less than that of the radon gas in the soil. This condition is
commonly caused by the use of appliances and fans in a relatively airtight
structure. Appliances requiring air
for combustion or other purposes lower indoor air pressure. This action draws in
the higher pressure radon laden air into the house through ground level cracks
and openings such as drains, sumps, floor cracks, foundation walls and water
supply.
Measurement
Levels:
The U. S. Environmental
Protection Agency (EPA) has established 4 picocuries per liter (pCi/l) or .02
working levels (WL) as the maximum acceptable continuous exposure level for
radon in a residence. This level is not considered a finite cut-off point,
rather it is a guidance point to determine when remedial action is advisable.
Measurements of 1-4Ci/l are
typically found in many houses in certain areas. This is considered a low level
which generally does not require any significant remedial action, depending on
the specific situation or occupant concern.
Some of the standard radon
mitigation methods are:
Forced Ventilation:
This
method utilizes fans or other mechanical means to exchange the radon laden
indoor air for outdoor air.
Heat Recovery Ventilation:
Through
means of a heat exchanger, this method utilizes the hot (or cold) air being
exhausted to heat (or cool) the radon free incoming air.
Sub-Slab Suction:
This
method utilizes vertical piping through the slab to draw the radon laden air
from below the structure to the outside.
Block-Wall Ventilation: With
this method, a solid horizontal duct is installed and sealed in place over the
horizontal wall/floor joint (or gap) around the entire basement perimeter. The
radon laden air is then mechanically vented to the exterior.
Pressurization:
This
method involves sealing off the basement from the rest of the house and then
delivering air from the upper floors to the basement, thereby increasing the air
pressure in the basement and keeping radon gas out.
Need additional information on
Radon: Radon Resources
