Your Results in Context

Ok, you have a number now, so let's put it in context.

First, since radon is radioactive, no level of radon is considered 'safe'. That being said, it is important to realize that radon is also unavoidable. It is everywhere - in all homes and in outdoor air as well. What we want to do is keep our radon exposure at the lowest level possible.

The average outdoor level is 0.4 picoCuries per liter (pCi/l) and the national average indoor level is 1.3 pCi/l. Keep in mind that the national indoor average includes a lot of homes that do not have basements. According to the state of Illinois Radon Program, the average indoor level in the Chicagoland area is 4.0 pCi/l.

Of the homes we've tested, we've found that 38% test at or above the Action Level. We will generally find results anywhere from 0.4 pCi/l to 40 pCi/l on a regular basis. The highest level we've found is 162 pCi/l, in Minooka. If you'd like to know more about the levels we've found in your town, click here.

So a little more now about the Action Level. Since no level of radon is safe, the EPA determined that the lowest level reasonably achievable in most homes should be the goal. With that in mind, they determined that with current mitigation technology, 95% of homes could achieve a level lower than 4.0 pCi/l and that is how the Action Level was set at 4.0 pCi/l.

Does that mean that all homes at or above 4.0 pCi/l must be mitigated? No, there is no state law requiring mitigation. Should homes at or above the Action Level be mitigated? Absolutely.

Ok, so your number was 3.9 pCi/l or below. Does that mean that you do not need to consider mitigation? That depends. Averages below 2.0 pCi/l are considered to be in the Ideal Range, and they likely could not be improved enough to warrant the cost or the effort. Levels from 2 to 3.9 pCi/l are considered in the Acceptable Range. The consumer should consider the cost/benefit ratio to determine whether or not mitigation is the right choice for them.

What's Next?

Well, that depends on why your test was performed.

If your test was done for a real estate transaction, the results of the first test are to be used to determine whether or not mitigation is warranted. Click here to view the state's Recommended Testing Strategy for Homes Involved in Real Estate Transactions. At this point the discussion of acceptable radon levels and proposed remediation become a point of negotiation. Common practice is that the buyer asks the seller to either mitigate the home or credit the buyer for the cost of a mitigation system and retest post mitigation if the results are at or above 4.0pCi/l.

If your test was done for your own benefit, you have a more complicated Recommended Testing Strategy for Home Environment Tests depending upon the type and results of your test.