Michigan's new rules on the sale of amped-up fireworks could result in a popping Fourth of July holiday sales season for large and small retailers around the state.

The Michigan Department of Licensing and Regulatory Affairs is processing more than 900 applications for consumer fireworks certificates it has received this year from people who want to sell fireworks. Out of the 900, 239 have been granted, and the others are under review. To receive the certificate, retailers must meet state requirements such as adequate insurance coverage. This year, it became legal to sell and buy a full line of fireworks in Michigan — such as bottle rockets and larger-grade firecrackers.

The tents, which can range from 800 to 1,600 square feet, traditionally are opened for 10 days to three weeks during the season.

During that time, sellers can make $20,000, said Julie Heckman, executive director of the American Pyrotechnics Association.

"In tents that sell the full line of products, in other states, we can (gross) $30,000, $40,000 no problem," said Bill Weimer, vice president of Youngstown, Ohio-based B.J. Alan Co. Inc., a distributor of Phantom and Wolf Pack fireworks. B.J. Alan will open 22 temporary tents in metro Detroit this year at 1,200 to 1,600 square feet each.

The most profitable fireworks are the high-end items, such as multiple-tube devices. The rule of thumb in the industry, Weimer said: The smaller the product, the less room for profit.

The actual boost in sales this season in Michigan is hard to predict because full-line products are just reaching the shelves.

When Utah opened its laws to allow the addition of just one type of aerial product, Weimer said, sales there increased almost 150 percent.

"What's going to happen the first year, you're going to have a fireworks tent on every street corner," he said. "First season, it's going to be like the Wild West."

As soon as Scott DeGross, general manager of the Wisconsin-based Fireworks Depot Inc., found out about Michigan's new law, he sent an advance scout to northern Michigan to "see what opportunities there are."

He discovered a landscape similar to Wisconsin's, where tourists tend to swell in one area during the summer. That's why Fireworks Depot decided to break into Michigan by launching stores in Traverse City, Ludington, Kalkaska and Gaylord in time to exploit the lucrative Memorial Day weekend. After that, the company will see how things go.

So far, the chain has pumped about $40,000 to $50,000 into the new stores and hopes to at least cover startup and operating costs in the first year, with profits expected after two or three years, DeGross said.

Dawn Rosel, manager of a Grand Rapids-area retail outlet of Black Diamond Fireworks LLC, a distributor of Big Fireworks products, said consumer response to the expansion of product offerings has been "fantastic." At the new store in Grand Rapids, Rosel walked among cases of 24 mortars selling for $69.99, a roll of 16,000 firecrackers for $79,99 and other fireworks — all previously banned in Michigan and now sold with the state's blessing.

"You couldn't buy any of this stuff last year," she said. "If it jumped up off the ground, it was illegal."

Black Diamond also is thinking of opening a store in Traverse City, said owner James Stajos. His family also owns Big Fireworks, a Lansing-based company that has been distributing pyrotechnics nationally for decades.

Big Fireworks has about 60 employees in Michigan, he said, and Black Diamond, his new retail business, has about 10, "but I'm adding people every day."

Elissa Burda, owner of Monroe-based Motor City Fireworks LLC, is opening one year-round, brick-and-mortar location in Mt. Clemens and has plans and permits to open four temporary tents in metro Detroit.Motor City Fireworks plans to spend more than $25,000 per 3,600-square-foot tent, Burda said, and each tent will be open for nearly three weeks around the Fourth of July.

Available at the tents will be more than 20 brands of consumer fireworks, ranging from sparklers and fountains up through Roman candles and multishot aerial repeaters to large "finale" items, such as mortars and shells.

Burda expects she'll need 60-80 people to run the tents, assuming she is able to open them all.

One area of confusion under the loosened restrictions is the role that municipalities have in enforcement.

For example, the Michigan Bureau of Fire Services and the licensing department granted Burda a permit for a temporary location in the city of Detroit, near Groesbeck and Eight Mile, but she has yet to see the green light from city officials.

When she went to apply for a tent permit, Burda said, Detroit officials told her she needed a permit to sell the fireworks within city limits. But that's not her understanding of the law.

Detroit has since updated its policy. The fire marshal’s office will not impose any regulations that are in conflict with the state law, said Detroit Fire Department Fire Marshal Herbert White. "The Detroit Fire Department Fire Marshal Division has already begun the process of addressing and resolving any conflicts between the existing Fire Prevention and Protection Code and PA 256 of 2011," White said in a statement. “Under the act, tents and canopies are approved retail locations for fireworks retail sales.”

The city of Auburn Hills was caught off-guard by the limiting language of the bill, said Steve Cohen, community development director. He said his department found out about changes to the law a month ago.

"After talking to our legal counsel, it was made very clear to us that municipalities are not allowed to regulate fireworks tents," he said.

His department is concerned with the aesthetics of the tents, such as location, signs and lights, and safety.

Cohen said he things the fireworks dealers will work with him but is concerned they don't have to.

"If they have proper permits from those two (state) agencies, the city of Auburn Hills or any other municipalities have no right to restrict their operation," he said.

Some fireworks dealers say the loosened rules will push smaller dealers out of business or force people to "go legit."

"The average guy who was selling it out of the trunk of his car probably will be forced out," said a dealer who asked not to be identified.

Either way, consumers win, said Black Diamond's Rosel.

"Probably 90 percent of the customers are glad they don't have to break the law, burn all that gas and spend all that money in a different state," she said. "Now they can do it all in Michigan."

Howard Lovy and Pat Shellenbarger contributed to this story

Correction: A previous version of this story incorrectly reported that the new fireworks law makes Michigan the only state in the Midwest to allow new temporary locations, such as tents, to be set up for the sales.