Health effects of secondhand smoke
The health risks from indirect, secondhand smoke are clear. 

• A 2006 report of the U.S. Surgeon General states that: "There is no risk-free level of exposure to secondhand smoke. Nonsmokers exposed to secondhand smoke at home or work increase their risk of developing heart disease by 25 to 30 percent and lung cancer by 20 to 30 percent. The finding is of major public health concern due to the fact that nearly half of all nonsmoking Americans are still regularly exposed to secondhand smoke."
  
• Short exposures to secondhand smoke can cause blood platelets to become stickier, damage the lining of blood vessels, and decrease coronary flow velocity reserves; all mechanisms that may increase the risk of a heart attack.
  
• A May 1997 report in Circulation: Journal of the American Heart Association  found that constant exposure to environmental tobacco smoke — in the workplace or home — nearly doubled the risk of having a heart attack. The 1997 study, which examined the data of more than 32,000 women during a 10-year period, was not the first to indicate the dangers of environmental tobacco smoke. In 1992 the American Heart Association's Council on Cardiopulmonary and Critical Care concluded that environmental tobacco smoke is a major preventable cause of cardiovascular disease and death. The statement urged that environmental smoke be treated as an environmental toxin, and that ways be found to protect workers and the public from this health hazard.

Health benefits of smoking bans
Existing data suggests smoking bans have a significant, positive impact on public health.

• In an October 2009 report (Secondhand Smoke Exposure and Cardiovascular Effects: Making Sense of the Evidence), the Institute of Medicine concludes that there is a causal relationship between smoking bans and decreases in acute coronary events. The report is based on 11 observational studies which found that smoking bans led to decreases in acute coronary events ranging from 6 to 47 percent.
  
• A September 2009 report published in Circulation: Journal of the American Heart Association found that one year after passing smoking bans, communities in North America and Europe had 17 percent fewer heart attacks compared to communities without smoking restrictions, and in those communities, the number of heart attacks kept decreasing with time.

AHA Advocacy Position
The American Heart Association advocates for comprehensive smoke-free workplace laws at the state and local levels, in compliance with the Fundamentals of Smoke-free Workplace Laws guidelines. Some of these principles include sufficient planning, emphasis on local initiatives, resource allocation, strong grassroots organization, readiness within the community, model policy language, and the need to incorporate expert advisors.

The AHA maintains that smoke-free laws should be comprehensive and should apply to all workplaces and public environments, that there should be no preemption of local ordinances, and no exemptions for hardship, opting out, or ventilation. Other exemptions to avoid include those for casinos and gaming organizations, bars, and private clubs. 

AHA Policy Position Statement on Clean Indoor Air Laws and the Impact on Cardiovascular Disease