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RADON411
$5

County radon report

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Locations and reportsGeographic comparison

Compare radon data between locations

Compare EPA radon zones and reported testing statistics between U.S. states and counties, with every gap in the data shown as a gap.

Choose two or three locations

Type or pick a state in each slot and compare. Once a state is selected, its counties are listed first in that same field, so choosing a county is a second pass through the same form.

Choose at least two locations

A comparison needs two places. Pick them above, or start from a state report and follow a county link.

What you can compare

EPA radon zone or zone coverage, the most recent reported year, buildings tested, the median reported result and the share of reported tests at or above 4 pCi/L.

What is charted

A bar chart is drawn only when every selected place holds that statistic. A chart with one real bar and two blanks invites the wrong conclusion, so it is not drawn.

What a gap means

An empty cell means the figure is not on file for that place. It never means zero, and nothing here is filled in from a neighbouring area.

Prefer to browse? All state reports · Query every figure in the data explorer