Close to enacting the first-of-its-kind law in the country, the San Francisco Board of Supervisors on Tuesday voted 10-1 in favor of mandating cell phone retailers to post the `specific absorption rate' (SAR) of each phone - thereby detailing the level of radiation emitted by each of the handsets.

Since the SAR rates essentially measure the amount of radio wave radiation that gets absorbed into the body tissue of the handset users, it is important that each manufacturer gets the SAR rates of the products registered with the Federal Communications Commission.

With the Board of Supervisors having clearly voted in favor of the ordinance, San Francisco Mayor Gavin Newsom, who supports the proposal, will likely sign it into law after a stipulated 10-day comment period and a final voting by the Board of Supervisors.

The law, which will be applicable only to the retail stores in San Francisco, is expected to become effective in February; with a $300 fine to be imposed on those who violate it. While California and Maine jurisdictions have also considered similar legislation, San Francisco will apparently become the first city to enact the law.

Talking to the Chronicle about the impending law, Tony Winnicker, a spokesman for the Mayor's office said: "We think this is a modest and very reasonable measure that provides greater transparency and information for consumers to whom this is a concern."