SAN FRANCISCO (AP) – Smokers in San Francisco can no longer light up in a restaurant’s outdoor seating area.

The law—approved by the city’s Board of Supervisors in March— went into effect this week.

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Restaurants must not post signs advising customers they can only smoke at the curb or in a spot that is at least 15 feet from exits, entrances, windows and vents.

Failure to comply could cost restaurants a $500 fine.

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Golden Gate Restaurant Association director Kevin Westlye told the San Francisco Chronicle the group supported the legislation once a requirement that restaurant owners police people smoking in front of their establishments was removed.

Westlye said restaurant owners want to protect their employees and customers from second hand smoke.

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