The Philadelphia Housing Authority's board of commissioners voted unanimously Thursday to ban smoking in all PHA units.

Housing officials said Philadelphia, with 80,000 low-income tenants, is the largest city in the country to enact such a prohibition. The new rules are to take effect Aug. 5.

According to a poll released by the PHA, 35 percent of respondents smoked or lived with a smoker, and 55 percent supported living in smoke-free housing.

Herbert Wetzel, the board's vice chairman, said PHA officials and public-housing residents worked for months to arrive at "a fair and equitable policy to move forward with." There was no debate before the vote.

Under the policy, smoking will be prohibited inside homes and on public-housing property except in designated outdoor areas.

Current or future tenants caught smoking in existing housing will be asked to attend counseling sessions, the regulations state, but will not face eviction. Those smoking in buildings that open after the ban goes into effect risk losing their leases if they violate the rules a fourth time.

Philadelphia's move follows a national trend. Public-housing agencies in other major metropolitan areas, including Houston, Boston, and Detroit, have also gone smoke-free in recent years. Maine banned smoking in public housing in 2012.

The moves come partly in response to federal pressure. Although the U.S. Department of Housing and Urban Development does not require local housing agencies to ban smoking, the agency took a stance on the issue in 2009, issuing a notice "strongly" encouraging smoke-free policies because of the health risks associated with tobacco use and secondhand smoke.

Public health officials, researchers, and interest groups have also called for smoking bans.

Since HUD's statement, more housing agencies have gone smoke-free, as officials in cities nationwide have also pushed to curb smoking - even from electronic cigarettes - in other public places. According to the agency, more than 500 local housing authorities now prohibit smoking in at least some properties.

Although PHA's board reached quick consensus Thursday to adopt the ban, which has been under discussion for about 31/2 years, the new regulations are not without opposition.

Asia Coney, the president of PHA's resident advisory board and a member of the board of commissioners, voted for the policy but acknowledged that not all residents stand behind it.

"The actual attitude as it relates to residents is mixed," Coney said after the meeting. Some, she said, have argued that the authority should not prohibit smoking, given that it is legal; others have pushed for a ban out of health concerns.

Greg Brinkley, president of Abbottsford Homes, served on a task force that informed the policy's creation, but said he opposes the language passed Thursday.

Given that tobacco is addictive, officials should help smokers, he said, rather than rushing to a ban.

"I can support it from a health standpoint, but not at the expense of people's rights," said Brinkley, a former smoker. "Some people smoke because they have to."

Kelvin A. Jeremiah, PHA's president and CEO, praised the policy after the vote, and said its ultimate goal is to encourage smokers to quit. Residents pushed back against eviction as a consequence of smoking violations, he said. He added that he hopes offering counseling instead will give smokers the tools to stop.

"This isn't just about punishing tenants," Jeremiah said, acknowledging that the agency will need to decide in the coming months whether the enforcement measures work.

Materials accompanying the resolution cited the federal government's stance against smoking as a reason for the ban; according to a PHA fact sheet, HUD has "indicated" that it soon intends to propose that public housing go smoke-free nationwide.

"We wanted to be ahead of the curve," Jeremiah said. "That's the national trend."

In other business Thursday, the board recognized 55 young PHA residents with college scholarships.