Don't be surprised these days if you find engineer Guy Arbour measuring the air quality around various terasses in the city. The device is supposed to prove that tobacco smoke barely registers compared to other pollutants in downtown Montreal.

Arbour was hired by well-known bar owner Peter Sergakis, who's wants to fight a proposed ban on smoking on outdoor terasses.

“What’s important in terms of health hazard is both the intensity and length of exposure,” Arbour said, adding the analysis is not yet complete.

Last month, the Liberal government tabled Bill 44, which will ban outdoor smoking on restaurant and bar patios.

Anti-tobacco groups contend that cigarette smoke often wafts indoors, putting the health of diners at risk.

Sergakis, who owns more than 40 bars in Montreal, has called the legislation hypocritical since the provincial government earns revenue from cigarette smokers.

In order to buttress his argument the president of the Union of Quebec Bar Owners commissioned a study of the micro-evironments on bar terrasses.

Sergakis said his study shows pollution from cars and trucks is worse than from cigarette smoke.

"In the street the emission is 10 times worse than what is on the terrasses. It's very minimum on the terrasses," said Sergakis.

He plans to present his data during public hearings.

"We don't believe the results that came out last summer. and we're going to present our results in Quebec, and hopefully they're going to listen to us because it doesn't make sense," said Sergakis.

Bar owners claim they lost up to 25 per cent of their business in 2006 when smoking was banned in bars and restaurants. But those numbers are being challenged by the anti-tobacco lobby.

Dr. Genevieve Bois of the Coalition Against Tobacco Smoking says such scare tactics aren't new.

“The cost will be about $50 per year per restaurant per year. That's nothing,” she said.

The coalition has also done its own studies about air quality on terrasses. And it's reached some far different conclusions.

“In some cases it can be as bad as it could be inside. That's why organizations like the World Health Organization ask that indoor and certain outdoor settings smoking be prohibited in order to protect non-smokers,” she said.

Quebec banned smoking indoors in bars and restaurants and other public locales in 2005.