The proposal comes from Supervisor Myrna Melgar, who wants to expand the city's indoor smoking ban.
"We know that smoking is linked to heart disease, respiratory disease, all types of illnesses like asthma," said Dr. John Maa, a member of the San Francisco Marin Medical Society.
His organization supports Melgar's proposal and says tobacco is the leading cause of preventable deaths in the United States.
While most health professionals support the ordinance, workers at many bars and taverns we spoke with fear it could drive away customers.
That concern among businesses is turning into action. As of Friday, more than a dozen establishments in the city have signed a petition urging policymakers to vote against the ordinance.
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On the streets of North Beach, we met Karim Salgado, who owns a bar called Legacy. She says she doesn't have time to enforce a smoking ban.
"I think that if the city wants to pass this ordinance, then the city should enforce it. It's not up to us," said Salgado.
Outside Legacy, customer reaction was mixed.
With some more accepting of a potential ban.
"I understand the health concerns and they're totally valid," said Luca Krasnow.
Others were strongly opposed.
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"It's ridiculous. I mean, if I'm out drinking why can't I smoke a dart outside?" said Owen Rees.
San Francisco has already banned smoking outside restaurants. It is the last major city in the Bay Area to allow smoking outside bars and taverns.
For people like Doctor Maa, the time has come to change that.
"It's time for San Francisco to be equalized with all of the other major cities all around the Bay Area," said Maa.
Melgar's proposal has to pass both a committee and the full Board of Supervisors before it can become law.