MINDEN " Elevated levels of radon no longer are detected at three Douglas County schools after heating and air systems in rooms were adjusted, school district officials said.
In March, tests found levels of radon exceeding the Environmental Protection Agency's guideline of 4.0 picocuries per liter in one room at both Gardnerville Elementary and Pau-Wa-Lu Middle schools and two rooms at Carson Valley Middle School.
But tests performed in April by Colorado Vintage Companies showed radon levels below 2.0 picocuries per liter at the schools after the adjustments were made to the heating and air systems.
In many cases, the rooms just needed more fresh outdoor air, which reduces radon entry as well as improves indoor air quality, according to the company.