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3.2. State Test Results Dissemination Requirements
State statutes and code regulations also differ in the dissemination of radon testing results to
the public. For example, a Colorado statute requires all schools to test for radon and to maintain
records of the test results for disclosure on request. In other words, schools in Colorado are not required
to share test results with the state agency that regulates radon tests in schools; nor are they required to
report the results to teachers or parents [24], unless such request were made.
A nationwide policy is therefore essential to mandate radon test reports to be submitted to
a designated state regulatory agency, to be disseminated to parents, other interested parties and
the district school board members, as well as to make the results available on the school’s or
district’s website. In Connecticut, for example, the school radon testing guide recommends that
the school administration conducts an informational meeting to provide an overview of scheduled
radon testing and address any questions/concerns to individuals responsible for radon testing and
representatives of parent and teacher organizations. In addition, in Connecticut, it is recommended that
two weeks prior to a scheduled radon testing, a formal letter of radon testing notification is required
to be sent to parents of students and school employees, along with radon educational materials.
Proper notification, in a transparent and timely way, will encourage civil society stakeholders to voice
their concerns and participate in monitoring policy and program implementation.
3.3. State Radon Mitigation Requirements
In the United States, a radon level below 2 pCi/L is accepted as normal (Radon Zone 3).
Indoor Radon level between 2 and 4 pCi/L is designated as Radon Zone 2 and the USEPA suggests
mitigation to be performed. Indoor radon level of above 4 pCi/L (Action Level) is categorized as
Radon Zone 1 where mitigation is deemed necessary because an increased risk for lung cancer has
been observed at that exposure level in smokers and non-smokers [25]. However, radon mitigation
requirements in most states varies substantially and often are not enforced (Table 1). For example,
the statute of state of Colorado doesn’t require schools to mitigate, so it’s up to the school district and
its constituents to address mitigation issues [24].
4. Radon Regulations in Europe
Although not the main focus of our review, radon in schools should be a concern in any
geographic region where levels are above those deemed to be safe. The EU recently enacted a directive
establishing 300 Bq/m 3 (~8.1 pCi/L) as a concentration threshold for both dwellings and workplaces
including schools in all European Union countries [16,26]. In Ireland, for example, remedial work
is required for any occupied classroom or office where the radon levels are greater than 200 Bq/m 3
(~5.4 pCi/L) [27–29]. In a pilot study conducted in Spain, 46% of the workplaces measured in Galicia
had radon concentrations higher than 300 Bq/m 3 , followed by 10.6% in Madrid. Nineteen percent
of all workers were exposed to more than 300 Bq/m 3 , with 6.3% exposed to radon concentrations
higher than 500 Bq/m 3 [26]. Nationwide radon maps based on indoor measurements have been
produced in countries such as the United Kingdom, Ireland, and Italy [4,30], which may facilitate
and optimize the search for schools with high radon concentrations and to identify areas for special
preventive actions during new construction [4,13,31]. In Italy, the Legislative Decree 241/2000 set
500 Bq/m 3 as the highest acceptable radon concentration in workplaces including schools [30]. With the
2013/59/Euratom Directive, the obligation is introduced for member countries to periodically prepare
and update a Radon National Plan in order to implement the set of actions necessary to reduce the
health risk associated with radon [30]. However, it remains to be seen whether certain barriers may
prevent some EU member countries from fully complying with the Directive. In time, this Directive
may serve as a model for standardized national U.S. regulations as they apply to radon testing
and mitigation.