For engineers, the debate involves whether traditional hvac systems can dilute the presence of environmental tobacco smoke (ETS) to sufficiently low levels so as not to be harmful to those who do not smoke. Nonsmoking groups say it's not possible regardless of the type of equipment used, while hospitality organizations say that proper ventilation and air filtration can make it almost impossible to detect ETS odors.
Several cities across the country have already banned the use of tobacco in restaurants and public gathering places, which delights nonsmoking groups. Smokers, however, contend that the use of tobacco is legal in the United States and as such, they have a right to use it in public.