Hey, Mister! Got a Way to Beat the Heat?

It’s 102 degrees outside, but Jennifer Sanders and a friend appear perfectly comfortable as they dine on an open-air restaurant patio. Their table is bathed in sunlight and cooled only by a spray of superfine mist.

“If it wasn’t for the misters, we wouldn’t be out here,” Sanders said as tiny water droplets enveloped her like mist on supermarket produce.

“I would be absolutely miserable without them,” said Rich Merchant, another patio diner.

Misting devices create cool havens in the desert, where shade is scarce and the shadow of a thin tree with meager leaves is considered prime parking territory.

People seek refuge beneath the bouncing particles of water in the outdoor areas of restaurants, malls and movie theaters. The devices also cool off diners in Palm Springs, golfers in Nevada and visitors to the replica of “The Simpsons” home outside Las Vegas.

“It’s amazing technology,” says Jonathan Marsh, president of MistAmerica Corp. of Phoenix, who first saw misters at a restaurant 10 years ago. “I walked out to the patio and it was 20 degrees cooler. I was just blown away.”

Misting devices can lower temperatures by as much as 22 degrees. They cool by forcing water through a tiny nozzle at high pressure, breaking it into tiny droplets that evaporate.

The droplets suck up heat from the air as they go from their liquid to gaseous state, Marsh said.

Some misters are mobile.

The 1.5-pound Misty Mate can be strapped to the body and has a flexible tube that allows users to spray themselves with refreshing mist. There’s even an ice-cold version: Simply fill the device with ice cubes for a burst of arctic mist.

Steve Utter, president of Tempe-based Misty Mate, said he invented the personal-size misters in 1989 for workers at his former construction company. “I thought, How can I make a personal air conditioner for my guys to wear?” he said.

Misty Mate also supplies a special misting system to Arizona’s professional football team, the Cardinals. A steel tube hangs over the players’ bench about every three feet for players to grab and douse themselves with mist.

Some are a little uneasy about all that mist.

“I like them but I think if no one’s sitting under them, they should turn them off. It’s a waste of water,” said Michelle Campbell of Phoenix, who lunched recently on a nearly empty restaurant patio.

Marsh said misters use less water than most people think. A system spritzing hundreds of baseball fans in a stadium during a four-hour game uses about as much water as 20 sprinklers watering the field for six minutes, he said.

Over the last decade, misting devices have grown into a $100-million industry, with about half of it devoted to misters that cool people, Marsh said.

The rest includes misters that cool and humidify greenhouses, suppress dust in garbage transfer stations and disperse chemicals to control odor in sewage treatment plants, Marsh said. In chicken houses, misters cool off chickens, keep the dust down and spray chemicals to kill flies.

Misters also can create special effects.

An amusement ride in Cancun, Mexico, has mist spurting from the bottom of a “rocket” when it blasts off. In Alabama, fog accompanies the “eruption” of a 40-foot volcano during a laser-light show.

Marsh’s company also has misters at the Miami Metrozoo and is doing a system for a Disney World exhibit this fall. He recently closed a deal to ship misting devices to Saudi Arabia.

“When I first saw them, I thought they were weird,” said Amy Harrington, a Nebraska resident who found herself lunching in the Phoenix heat recently under a cool spray of mist. “Now I think they’re great.”

Sanders loved the misters so much that she installed a system in her home’s back porch for her dog. She even persuaded her lunch companion, Carol Whitty, to install a misting system for her dog.

“During the day, he just won’t go outside,” Whitty said of her pet pooch. “He just looks at you like, ‘Oh, please, don’t make me go.’ ”