Since March 31, smokers have had to step outside Minneapolis bars and restaurants to smoke a cigarette.

But has air quality in these establishments improved?

According to an indoor air quality survey released by the Minnesota Partnership for Action Against Tobacco last week, the air in Minneapolis bars is 99 percent cleaner since the smoking ban took effect last spring.

The partnership’s mission is to reduce tobacco use and exposure to secondhand smoke through research, action and collaboration, according to the group’s Web site.

The study monitored the air in 25 bars and restaurants in Hennepin County, which has a full smoking ban; Ramsey County, which has a partial ban; and Dakota County, which has no ban.

Patrons in Ramsey County and Dakota County bars and restaurants breath air that exceeds the Environmental Protection Agency’s annual exposure limit by 2.5 to 3.5 times, according to the study.

The survey also found that the air in Ramsey and Dakota county bars and restaurants is three times more polluted than downtown bus terminals during rush hours.

The antismoking group measured the air for cancer-causing chemicals and other compounds that can be inhaled and are found in secondhand smoke.

According to the group, these pollutants found in secondhand smoke cause 35,000 Americans to die of heart disease every year.

Also, secondhand smoke has been known to cause lung cancer, heart disease, chronic lung ailments and low birth weights.

Sue Jeffers, owner of Stub & Herbs, called secondhand smoke one of the biggest scams ever perpetrated on the American public.

“That’s as stupid as taking all of the cars off of all of the roads and saying the emissions are down,” she said.

Since the smoking ban, Jeffers has spent $30,000 to build a deck to try to lure smokers back.

“My smoking customers have taken their friends and have gone to St. Paul,” she said.

Jeffers said business is better since students are back; she calls them “a resilient group.”

Matt Perrin, a junior Japanese student, said he understands why the smoking ban was passed, but misses smoking at his favorite coffee shop, Pandora’s Cup, in Uptown.

“I would drink and do homework; it was like a home away from home,” Perrin said.

First-year student Fatima Asamarai said she thinks the smoking ban has been good for people’s health.

“I think that it is intrusive for nonsmokers when they have to be around smokers,” Asamarai said.

Hennepin County bar owners will protest the antismoking ordinance at 3 p.m. Thursday at Minneapolis City Hall, Jeffers said.