Michael R. Bloomberg Calls for Smoking Policies in Residential Buildings The owners of residential buildings would have to adopt smoking policies and disclose them to prospective apartment buyers and tenants, under a law proposed Wednesday by Mayor Michael R. Bloomberg, who has made curbing smoking a cornerstone of his public health policy. The bill would require buildings with three or more apartments - whether rental, condominium or cooperative units - to disclose whether smoking is allowed in all indoor and outdoor locations, including inside apartments, on balconies and rooftops and in courtyards. Mr. Bloomberg said at a news conference on Wednesday that he was proposing the bill because New Yorkers wanted to be protected from secondhand smoke. He insisted that the disclosure requirement would be strictly informational, and not a backdoor attempt to pressure landlords and buildings to ban smoking. "We protect people from hurting themselves if they're trying to jump off a bridge, we restrain them," Mr. Bloomberg said. Should you really do it with smoking? We're not going to do it with smoking, but we - this is purely an informational thing. The proposal, which calls for $100 fines for violators, received guarded but positive reviews on Wednesday from the real estate industry. Steven Spinola, president of the Real Estate Board of New York, said many rental buildings already had smoking policies, but that they usually applied to common areas like laundry rooms, not to apartments. But Mr. Spinola said that by compelling buildings to come up with smoking policies, the bill raised issues that still had to be clarified, like who would be responsible for enforcing the rules and paying the fines, and whether the rules could be enforced. "If somebody in management says to the person, "You're not allowed to smoke here," and the person ignores it, what do you do?" Mr. Spinola wondered. What is the role of the management of the building, or the owner or co-op board or condo association? Mr. Spinola said that preventing people from smoking in their own apartments would be particularly fraught. "I'm told there's a gray legal issue as to whether or not you can impose that, and you probably can't impose it on somebody who was already living in that apartment," he said. I'm told there's never really been a precedent by a judge as to what you can and cannot do. There's always been a legal settlement. The city's 311 complaint hotline got 2,363 calls complaining about secondhand smoke in residences from July 15, 2011, through Sunday, city officials said. The draft bill says that more than 50 percent of adults living in apartment buildings in New York City have reported being exposed to secondhand smoke from neighboring apartments creeping through cracks and ventilation systems. Christine C. Quinn, the City Council speaker, said Wednesday that she had not yet seen the bill, but that it would be sent to the appropriate committee for review. The mayor's statement compared the bill to laws already in effect requiring landlords to disclose lead paint hazards, or a history of bed bugs.