A new smoke-free ordinance will take effect Friday in the city of Portland. The law prohibits smoking before 10 p.m. within the outdoor areas of restaurants and bars that serve food.

Mayor Ed Suslovic will be joined by members of the Health and Recreation Committee and local health organizations in a 3 p.m. kickoff ceremony at the Porthole Restaurant on Custom House Wharf.

Earlier this year, the City Council enacted an ordinance prohibiting smoking within 20 feet of city-owned beaches, playgrounds, or athletic facilities.

The ordinances are designed to decrease involuntary exposure to secondhand smoke. Secondhand smoke contains more than 4,000 chemicals, of which at least 60 are known to cause cancer.

According to a statement issued by the city, research from Tufts and Stanford universities found that even in an outdoor setting, anyone who is up to 20 feet from a person who is smoking may be exposed to high levels of second hand smoke.

For more information about the city's smoke-free ordinances, visit the city's website.