And it is one of only a handful nationwide that have taken small but symbolic extra steps: prohibiting tobacco of any kind (and electronic cigarettes) anywhere on the property, including parked vehicles, and applying the policy to employees, contractors, residents, and guests.
"My goal is the health of our residents," said Dale Gravett, the authority's executive director. He said the policy was posted six months before it became effective on Aug. 1, and free smoking-cessation classes were offered, often at residents' buildings, by local hospitals and health-care organizations.
He said that it was overwhelmingly supported by tenants, and that there had been few complaints. The ban affects about 600 tenants.
Around the country, initial concerns from smokers typically turn into acceptance fairly quickly, said Ann Klassen, a professor at the Drexel University School of Public Health who has studied the issue. The argument that it's unethical to evict someone who may be addicted to nicotine and unable to afford private housing has a counterpart, she said: "Somebody shouldn't risk their health in order to get public housing."
More than 400 public housing authorities have adopted smoke-free policies nationwide, according to the U.S. Department of Housing and Urban Development, which encourages but does not require the change. Many are in California. The closest is Wilmington's. The biggest is Boston's.
Secondhand smoke is estimated to cause 46,000 adult deaths a year from heart disease and 3,400 from lung cancer, and it can linger as "thirdhand" smoke, attaching to carpets and furniture, and later transferring to people. It is linked to bronchitis, pneumonia, sudden infant death syndrome, and more frequent and severe asthma attacks.
Asthma is far more common in children from low-income households than the better off, and smoking is as well.
Chester County was ranked the healthiest in Pennsylvania on various measures by the Robert Wood Johnson Foundation, one of which is smoking: Just 13.3 percent of all adults smoke, according to the 2012 Southeastern Pennsylvania Household Health Survey. But 29.1 percent of those in the county who live below the federal poverty level (about $22,000 for a family of four) smoke.
"You can smell it coming through the door," said Carolann Thomas, 62, president of the Chester County Housing Authority residents' council, who quit smoking four years ago after 41 years.
"A lot of people don't recognize that about two-thirds of the air in an apartment unit come from outside that unit," said Giridhar Mallya, director of policy and planning for the Philadelphia Department of Public Health. Mallya headed a media campaign against secondhand smoke that the city launched in April.
The ads were guided by the findings of a new study he cowrote that examined what sort of messages influenced people to make their homes smoke-free. One said: "SECONDHAND SMOKE KIDS suffer more ear infections."
Mallya is working with the Philadelphia Housing Authority to pull together smoking-cessation resources for an eventual policy change. Studies have found that smoking bans, no matter where, are an extra push for smokers to seek help quitting.
If the city housing authority, with nearly 80,000 residents, goes ahead with a smoke-free policy, it would be the largest in the country so far. Chester County's has just 1,200 residents, and only half of them live in the six buildings that it owns outright and that are covered by the ban. Gravett, the executive director, said he would work with the company that owns the rest to expand the policy to everyone.
Only verbal warnings have been given so far, he said. The policy calls for two sets of written warnings, followed by possible eviction. It is included as an addendum to the lease, which in most cases runs month to month.
No one has refused to move in, and prices in Chester County - rents average more than $1,000 a month on the open market, Gravett said, vs. $288 in public housing - make it unlikely that people will drop off the waiting list.
Smoke drives up painting and cleaning costs and hurts marketing, he said. "You walk up to a unit and you see a bunch of people smoking like chimneys on the front porch," he said, "it looks bad."
Why take the unusual step of banning chewing tobacco and snuff, which neither look bad nor generate secondhand smoke?
"The health of our residents," said Gravett, including those who want to use the products.
Tomas Aguilar, director of health promotion and risk reduction for the Pennsylvania Department of Health, said he supported the broader policy because it helps set an example. "We're all in some respects looking out for the kids, for the folks who can't necessarily make a decision for themselves," he said. Even electronic cigarettes, he said, are a nicotine-delivery system.
Enforcing a ban against products that don't create smoke is far harder. But enforcement is only part of the point, said Thomas Carr, director of national policy for the American Lung Association.
"Honestly, when you put a policy in place, the vast majority of people will follow it for themselves," he said.
But Michael Hennessy, a senior research analyst in health and political communication at the Annenberg Public Policy Center, questioned the impact of mandates. "Voluntary regulation by smokers in households with smoke rules would have much more effect," said Hennessy, lead author of the recent study on secondhand-smoke messaging published in the journal Nicotine & Tobacco Research.
Marie Brickus, 67, an occasional smoker and resident of West Chester's 222 N. Church St. Towers, doesn't like the rule, either. "If I want to smoke, I feel I should be able to," she said. "Everybody is on restricted income here. People can't afford to leave."
Another resident, Danny Rosa, 63, had a slightly different take.
Rosa used to smoke in his apartment. Starting last month, he began going to the parking lot across the street, off Housing Authority property. That was an incentive to quit, he said, but he didn't actually do it until Thursday - one day after his doctor told him he was "pre-emphysema." He supports the new policy.
"Some people have come to me complaining about the rule," Rosa said. "But if you want to live here, you can't smoke here."
Contact Don Sapatkin at 215-854-2617 or firstname.lastname@example.org.