1.What is Radon?
It is a colorless, odorless, tasteless and naturally occurring gas. It is also radioactive, and radon is considered to be the second leading environmental cause of lung cancer in the US after cigarette smoking.
2. Where does it come from?
Radon is generated when uranium metal spontaneously decays. Uranium is a radio-active element present in small quantities in certain rock formations.
3. How does it get into houses?
It enters buildings from the ground through cracks and holes in the buildings’ concrete floor and occasionally the foundation walls. Molecules of radon gas are heavier than air but are small enough to go through cracks in concrete that are too small to see.
4. What causes radon to enter homes?
Radon gas enters buildings because the pressure of the radon gas pushing up from the ground towards the house is greater than the pressure of the air in the house pushing down. Slight changes in air pressure in the house will affect radon levels including barometric pressure, and the action of exhaust fans in the house. As a result, radon levels are always slightly changing.
5. How do I test for radon?
Because radon levels fluctuate continuously, radon tests should be done for a minimum of 48 hours and no more than 96 hours. Radon tests can be done with activated charcoal test kits and electronic monitors. The EPA standards for radon testing require windows in the house to be closed for 12 hours before the test is started and during the period of the test. Exterior doors can be opened for normal going in and going out. Radon test kits are available at local home centers and from Radon Home Services. Contact us if you wish to purchase one.
6. What are acceptable levels of radon?
According to the EPA, radon mitigation should be done when radon levels in the lowest living space or lowest livable space (see below) equal or exceed 4 pCi/l (4 picoCuries per liter of air). The EPA recommends testing the lowest living space for owner-occupied homes and the lowest space suitable for living in homes that are being sold. A basement can be considered living space if there is a playroom, exercise room or office in the basement. A basement can be considered livable space if it a buyer could use it for living space without renovations. For example, a basement in a 19th century farm house with a dirt floor and 5 foot ceilings would not be considered livable space, and radon tests should be conducted on the first floor of such a building. See EPA publication “Home Buyer’s and Seller’s Guide to Radon.” available at http://www.epa.gov/radon/pubs/hmbyguid.html
7. How is radon mitigated?
There are several radon mitigation techniques for existing homes. The first step in any radon mitigation project is to seal any large holes that connect the ground to the basement or living space. These holes can include open sump crocks, open perimeter drains and dirt floor crawlspaces.
Although sealing holes is necessary, it is not sufficient by itself to reduce radon levels significantly. Additional measures are almost always necessary. The most common method is called sub-slab depressurization (SSD). It is done by drilling a 4” diameter hole through the basement floor. A vertical 4” PVC pipe is placed in the hole and the pipe is directed out of the building. An inline fan is mounted in the pipe and suction is applied to the hole. This suction causes radon gas to flow towards the piping system and away from the living space.
8. Does it matter how the radon mitigation system is installed
Yes, it does. There are national standards for the design of radon mitigation systems. These standards were created to ensure that systems worked efficiently and, more importantly, safely. A national Radon Mitigation Contractor certification program was also established to ensure that these standards would be followed when radon mitigation systems are installed. You should always have radon mitigation systems installed by a nationally certified radon mitigation contractor.
9. Why is the post-test important?
The post test is a measure of the effectiveness and performance of the mitigation system, and it confirms that radon is below 4.0 pCi/L in the area that was pre-tested. You should always have a post-test done when your radon mitigation system is installed.
10. How much do radon mitigation systems cost?
The cost of radon mitigation systems varies depending on the structure of the house. A basic one penetration sub-slab depressurization system can cost up to $1200. If additional slab penetrations are necessary or crawlspace, perimeter drain or sump sealing is required, the cost will increase. Radon system costs rarely exceed $2500.
11. If I have more questions, where can I find help?
Radon Home Services (RHS) is happy to provide you with as much information as possible. Call us at 315-422-6000 or
315-471-0324 any time or email us at: firstname.lastname@example.org