SAN FRANCISCO (KCBS) – The nation’s first cellphone ordinance, which requires that retailers provide customers with information on how to limit their exposure to radiation from the devices, has gone into effect in San Francisco.

The legislation calls for stores to display an informational poster at the point of sale in outlets and that fact sheets be given to anyone who requests it or buys a cellphone.

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KCBS’ Anna Duckworth Reports:

A customer at the Market Street T-Mobile in San Francisco, who works as a scientist, said the ordinance is a waste of time and taxpayer money.

“I strongly disagree scientifically. It has not been proven that it really has an impact,” he said. “If it is scientifically proven, then it should be federal regulation.”

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Most experts have said that the way cellphone radiation is measured can be unreliable as exposure can depend on many different factors, including distance from a cellphone tower, battery life and how close the phone is to a person’s body.

The poster and fact sheet recommend limiting cellphone use by children, turning off your phone when it’s not in use and using a headset, speakerphone and texting option to keep the phone away from your body.

The World Health Organization has classified cellphone radiation as a possible carcinogen. Compliance with the law is required by the end of October.

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