The Maryland Zoo in Baltimore announced Wednesday that it will no longer permit visitors to smoke on its grounds beginning July 1.

The zoo said that it will ask visitors to leave the grounds to smoke or use tobacco products, including e-cigarettes. The zoo had previously prohibited smoking inside buildings under the Clean Indoor Air Act of Maryland, which was passed in 2007.

The zoo's decision comes after the City Council voted this year to ban smoking near playgrounds, swimming pools and ball fields.

If visitors choose to leave to smoke outside the zoo gate, they will be granted re-entry, according to a statement from the zoo.

The zoo has allowed visitors to smoke in designated areas for more than 15 years.

But zoo President and CEO Don Hutchinson said that exposure to secondhand smoke has been the No. 1 complaint from zoo visitors.

Zoo spokeswoman Jane Ballentine said in an interview that visitors compared the zoo to Oriole Park at Camden Yards, where smoking is not allowed, and questioned the zoo's promotion of nature and conservation in light of its smoking policy. In addition to Camden Yards, M&T Bank Stadium also banned smoking in 2013.

The zoo was "getting more and more complaints from guests about other guests not using [designated smoking] areas," Ballentine said. "It seemed to be becoming a little bit more of an issue."

After a year of considering going smoke-free, the zoo decided to do it this summer because of increased visitation expected with new exhibits, including the penguin exhibit and the Maryland Wilderness Marsh Aviary, opening in the fall, Ballentine said.

Ballentine said the decision is about the "customer experience."

"We're always trying to listen to guest comments," she said.

Rick and April Kennedy have visited the zoo with their 20-month-old daughter and said they think it's a great policy.

"So many children are here; they don't need to be exposed to secondhand smoke," said April Kennedy, who said she got asthma as a child because of secondhand smoke. "[Smokers] are affecting my health as well as theirs."

Zoo officials expect that some visitors will be upset by the decision, Ballentine said.

Before deciding to go smoke-free, the zoo looked to other open-air facilities in the city and contacted other accredited zoos and aquariums to see whether going smoke-free had worked for them. Two-thirds of the 223 other accredited zoos and aquariums nationally are smoke-free, Ballentine said.

Of the facilities that Ballentine spoke with, there were "generally a couple people not happy," but the issues were resolved when smokers were approached politely by staff, she said.

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