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Radon Levels

Radon is an odorless and invisible radioactive gas naturally released from rocks, soil, and water. In outdoor environments, radon levels are very low and generally not considered harmful. But when radon gets into homes or buildings through small cracks or holes and builds up to higher levels over time, people can get lung cancer by breathing in the air. The Environmental Protection Agency (EPA) considers radon as the number one cause of lung cancer among nonsmokers and the second leading cause of lung cancer overall. To determine if mitigation should be performed, measured indoor air concentrations of radon are compared to the EPA action level of 4 pCi/L. EPA also suggests mitigation be considered if a test shows between 2 and 4 pCi/L.
This indicator reports the radon testing prevalence, i.e., the proportion of residential buildings tested for radon, as well as the mean, median, and maximum pre-mitigation radon levels of tested buildings, over the ten-year period from 2008 to 2017. Data are collected from national radon testing laboratories (or from states for NJ and KS) and are released by CDC National Environmental Public Health Tracking Network (CDC EPHTN).
Note:
1. For KS and NJ, since the ten-year total lab radon data are not available, annual state radon data are aggregated and reported as an alternative, as suggested by CDC EPHTN.
2. This indicator only reports the pre-mitigation data which is regarded as a better representation of the radon levels in an area. However, the pre-mitigation data also include those tests not designated as pre or post since not all states identify if a test is pre or post mitigation.

Source

Centers for Disease Control and Prevention, CDC – National Environmental Public Health Tracking, 2008-17.

Source Description

Since 2002, the CDC National Environmental Public Health Tracking Network (CDC EPHTN) brings together health data and environment data from national, state, and city sources and provides supporting information to make the data easier to understand. The Tracking Network has data and information on environments and hazards, health effects, and population health.

Methodology

Radon test data are obtained from the CDC Environmental Public Health Tracking division. Data for all the states except KS and NJ are collected by labs on a 10-year basis while data for KS and NJ as presented in this indicator are from annual state radon data because for these two states the lab radon test data are missing across all the years. Since CDC EPHTN recommended users to refer to the state radon test data for these two states, CARES back-calculated the 2005-2017 ten-year (four ten-year periods) counts/rate for all the counties of the two states and combined the records with the ten-year lab radon test data for the other states.

Measures for this indicator are derived as follows by CDC EPHTN:

  • The rate of housing units tested per 10,000 units over a 10-year period is calculated as number of tested residential housing units divided by total number of residential buildings.
  • The mean, median, and max pre-mitigation* radon level in tested buildings are calculated as mean, median, and max value among pre-mitigation or unknown mitigation tests.
  • The number of pre-mitigation* radon tests by radon level (cut-points: <2, 2-4, >=4 pCi/L Radon) as presented in the breakout table is calculated as the number of pre-mitigation or unknown mitigation tests in radon level.
  • The percent of pre-mitigation* radon tests by radon level (cut-points: <2, 2-4, >=4 pCi/L Radon) as presented in the breakout table is calculated as the number of pre-mitigation or unknown mitigation tests in radon level divided by the total number of pre-mitigation or unknown mitigation tests.

    • *All pre-mitigation data includes those tests not designated as pre or post mitigation.

    For more information, check out the indicator’s documentation page in the CDC EPHTN website.

    Data Breakouts Available

    • High Radon Level (>= 2 pCi/L)
    • Prevalence of Elevated Radon Levels
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