Buying a house can be a bit like falling in love. You shop around, seek advice from friends, and when you find the perfect match, lay it all on the line and pop the question. But even after a seller has said yes to your offer, you'll need to complete a home inspection, which often includes a radon test.

Radon test results usually arrive a week or two after your home inspection report and can be riddled with terrifying facts about this deadly gas. If it reveals high levels, you may be left wondering whether you should walk away from the sale. You don't have to. Here's why.  

A Radon Problem Can Be Fixed

Radon-related lung cancer kills an alarming 21,000 people each year, a tragedy multiplied by the fact that significant exposure to the gas can be easily remedied. The scope of the work depends on the level of gas and the style of your house, but it's pretty simple and not overly expensive.

According to the Environmental Protection Agency, radon is found in every state. It's a naturally occurring radioactive gas produced by the breakdown of uranium in soil, rock, and water. Because the air pressure inside a house is typically lower than the pressure in the soil around its foundation, radon is drawn into the home through cracks in the foundation and other openings.

Radon levels are measured in picocuries per liter, or pCi/L. Levels of 4 pCi/L or higher are considered hazardous. Radon levels less than 4 pCi/L still pose a risk and in many cases can be reduced, although it is difficult to reduce levels below 2 pCi/L.

The EPA estimates that a radon removal system costs about $1,200 for an average house. The system is usually comprised of one or more PVC pipes that run from the radon-emitting soil beneath a home up through the roof. An in-line fan draws air through the system so that it doesn't leach into living spaces. Once installed, a follow-up radon test is done. Even in houses with extremely high radon levels, you can expect a drop to levels considered safe.

You Can Ask for a Seller Credit

If a radon test reveals high levels—anything above 4 pCi/L—ask for a walk-through with an EPA-licensed radon remediation specialist. You can find one through your state radon office. Most will provide a free remediation estimate, and, if the work is done, guarantee that radon levels will be acceptable.

Ask the seller for a price reduction that covers the estimated cost of remediation. If the seller balks, have your agent remind his or her agent that it's a problem other buyers are likely to encounter as well. Depending on your state, the agent may even be required by law to disclose the radon test results to other potential buyers on a seller's disclosure form.  

A Single Radon Test Offers Only a Snapshot

Relying on just one radon test done as part of a home inspection is a mistake, even if it reveals that the home has safe levels. In our tests, test kits that measure long-term levels—90 days or more—were far more accurate than the one-week tests used by most home inspectors. That's because radon levels fluctuate day to day and season to season.

In our evaluation, only one short-term radon test was accurate enough for us to recommend. Two kits undercounted radon levels by almost 40 percent. So by all means, let your home inspector test for radon and use the results as a bargaining chip to ask a seller for a credit if radon is detected. Just don't think of it as the final word. You'll still want a more thorough radon test done after the sale has closed. 

Need more info? Check the radon information section of the EPA's website. If you're buying or selling a home, print out the EPA's pamphlet on radon and keep it with your files.