The debate over airport smoking rooms is flaring up again.

In May, just a few months after the 25th anniversary of the federal law banning smoking on domestic U.S. flights, Vice Admiral Vivek Murthy, the U.S. Surgeon General, posted a photo on Facebook and Twitter giving thumbs down to smoking rooms at Hartsfield-Jackson Atlanta International Airport.

Now, several anti-smoking groups are publicly urging Salt Lake City International Airport, which currently has five smoking rooms, to make the airport’s new main terminal — scheduled to open in 2020 — entirely tobacco-free.

“In a state that does not allow smoking in other major public places and workplaces, it is time that the Salt Lake City International Airport do what is right to protect the health of all of those who utilize it by eliminating all the indoor smoking rooms,” said Brook Carlisle, Utah government relations director for the American Cancer Society Cancer Action Network.

For now, the plan is to keep the smoking lounges as a benefit to smokers who make connections at the airport, says SLC spokeswoman Bianca Shreeve.

The lounges “not only segregate smokers from non-smokers, they keep smokers with short connections from trying to smoke in areas they are not supposed to,” she said.

Initially paid for by Phillip Morris and built before the 1996 Olympics, the twelve smoking lounges at Atlanta’s airport “are an amenity that many of our passengers still use,” said ATL spokesman Andrew Gobeil. “There are no immediate plans to close them.”

In addition to SLC and ATL, there are public indoor smoking spaces in several other major U.S. airports, including Washington Dulles International, McCarran International in Las Vegas, and Denver International.

Nashville International Airport has two Graycliff smoking lounges accessible to those paying an entrance fee. T.G.I. Friday’s, in the middle of Concourse D at Miami International Airport, has a smoking lounge for patrons and the Smokin’ Bear Lodge Smoking Lounge located behind the Timberline Restaurant at Denver International Airport is accessible with a $5 minimum purchase from the restaurant.

At Dallas/Fort Worth International Airport, there is a smoking area inside the Admirals Club in Terminal A, although American Airlines says that smoking policy is “under evaluation.”

Dulles Airport has four smoking lounges and considers them an amenity for the “broad cross section of passengers we serve, which includes a large number of international travelers and domestic travelers boarding or getting off long transcontinental flights,” said airport spokesman Christopher Paolino.

In Las Vegas, McCarran International Airport allows smoking in select bars and gaming areas.

While the number of U.S. airports offering smoking spaces has declined in the past ten years, a CDC study found that the average air pollution levels from second-hand smoke directly outside designated smoking areas in five large hub U.S. airports — Washington Dulles, Denver, Salt Lake City, Atlanta and Las Vegas — were five times higher than levels in smoke-free airports.

“Given all the science that we have and the fact that so many cities and states are working towards going smoke-free, the fact that airports aren’t going in that direction more quickly is disconcerting,” said Cynthia Hallett, executive director of Americans for Nonsmokers’ Rights.

The U.S. Surgeon General agrees. “We know second-hand smoke kills,” said Vivek Murthy via email. “By making our indoor spaces — like airports — smoke-free, we can help prevent 41,000 deaths each year in the U.S.”

(My story about airport smoking rooms first appeared on USA TODAY as an At the Airport column.)