BERKELEY, Calif. (AP) — A federal judge has allowed Berkeley to start requiring cell phone retailers to warn customers about possible radiation risks.

The San Francisco Chronicle reports that U.S. District Judge Edward Chen of San Francisco says the city can require retailers to say carrying switched-on phones too close to a person’s body might violate federal radiation standards.

READ MORE: Clinics Adapt As Pause Put On Johnson & Johnson Vaccine Distribution

Chen blocked Berkeley from making such notifications in September, when CTIA-The Wireless Association filed a lawsuit arguing the rule violated freedom of speech.

READ MORE: New Evidence Leads To Arrests In Kristin Smart's Murder Case

But Chen ruled Wednesday the warnings can be enforced now that Berkeley removed a disputed claim that the potential risk is greater for children.

MORE NEWS: Johnson & Johnson Pause Sends Some Clinics Scrambling, Fuels Worry Of Vaccine Hesitation

CTIA is asking a federal appeals court to declare Berkeley’s rule unconstitutional.