Community Corner

San Mateo County Cancerous Radon Level below National Average

Traces of dangerous radon are found in all homes, but there are ways to protect yourself from it.

Radon — a tasteless, colorless, odorless gas — is everywhere. It comes from the decay of uranium in soil and then accumulates in homes, where it can become dangerous. 

According to the Environmental Protection Agency (EPA), "elevated levels of [radon] are the leading cause of lung cancer among non-smokers."

Radon in buildings is measured in picocuries per liter (pCi/L). What that actually means is less important than knowing when your home has exceeded the safety threshold of radon pCi/L. EPA standards place the "take action" level at 4 pCi/L, meaning if radon levels reach or surpass that in a home, business, school or other building, the stewards of that building should do something about it. 

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The national indoor average radon level is 1.3 pCi/L, far below the level necessary to take action. In San Mateo County, according to the website California Radon Information, the average level is actually lower, at 1.2 pCi/L. But that's not the case everywhere in California. In Santa Cruz County, they are much closer to the danger zone at 3.6 pCi/L. Seven percent of homes in San Mateo County are above the 4 pCi/L threshold. 

In a recent radon testing sweep of the county, Atherton tested off the charts with 34 percent of homes in the danger zone, followed by Menlo Park at 24.4 percent, Redwood City at 16.1 percent and Belmont at 12.7 percent. Conversely, there wasn't a single test above 4 pCi/L in Millbrae, and a rate of just 2.2 percent in South San Francisco, 6.8 percent in San Bruno and 2.3 percent in Burlingame.

Find out what's happening in San Brunowith free, real-time updates from Patch.

High radon levels do not doom us all to cancer. There are a few steps that can be taken to prevent risks presented by radon:

  • Test. There are do-it-yourself radon testing kits available online and at hardware stores.
  • Fix: Contact a radon reduction contractor if your radon level is too high.
  • Save a Life: According to the EPA, 21,000 people die of lung cancer every year. Staying on top of dangerous radon levels is an easy way to prevent death.

To find a qualified radon professional, obtain a test kit or contact your state radon office, visit www.epa.gov/radon or call 1-800-SOS-RADON.


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