In the early 1970s, the market for fireworks was heavily regulated in many states. But not so much in Tennessee.

Back then, Glenda Tinnin and her husband ran a souvenir shop and restaurant alongside a highway in the state. Their business was doing pretty well, but then an even more sparkling opportunity lit up their entrepreneurial ambitions.

"My son, who was 12 at the time, started selling fireworks out on the front porch, and he was doing better business than we were," Tinnin says. So they decided their roadside business should blast off in a new direction.

Glenda and her husband began selling fireworks at their store. And they put a big hand-painted sign on their storefront: Hee Haw Fireworks, which was emblazoned in red capital letters.

Today, 49 years later, Hee Haw Fireworks has rows and rows of explosives filling their store. "We have the Death Shell, Nishiki, Excalibur," Tinnin says. There's also one called "One Bad Mother" and "One Bad Mother In Law" and — our personal favorite — the Mother Of All Bombs, or M.O.A.B. "All the good brand names we carry."

Since Glenda began selling fireworks, the market for them has changed a lot. The changes really picked up the pace after 1972, when Congress set up the U.S. Consumer Product Safety Commission (CPSC). Fireworks, with their history of maiming people, were one of the agency's first targets.

Jay Zagorsky, a professor at Boston University's Questrom School of Business, says the CPSC has worked to make a whole bunch of changes to fireworks over the years.

"One, they made sure for a rocket shooting off, that the bases were stronger and longer, so that the rockets didn't tip over, and then you had a rocket shooting along the ground at spectators," Zagorsky says. "The second thing that they did is they made sure fuses were consistent. Because oftentimes — before [the CPSC] came along — you could light a fuse and you had no idea if it was gonna blow off in a couple of seconds or it was gonna take a long time, causing some people to walk over going, 'Hmm, is this a dud?' And then it would blow up in their face."

Zagorsky says the agency also made sure fireworks contained no prohibited chemicals, including lead. Before these regulations were imposed, fireworks would "explode in a spectacular color, but basically rain down poisonous chemicals," he says. The agency also helped the industry standardize fireworks. "And that meant, basically, your cherry bombs and your firecrackers all had the same amount of kaboom."

Tinnin says these regulations changed the products they got in their store. "And we were glad of that because it made it safer," she says.

An Exploding Market

Business at Hee Haw Fireworks has been good, and, over the years, it's been helped by the fact that residents of nearby counties and states haven't been able to buy fireworks as easily as you can in Tennessee. "A lot of people from Kentucky and Indiana" come and buy fireworks from them, Tinnin says. "In fact, I got a man coming in today. He was actually our first customer. And he's from Louisville, Kentucky."

While it's still easier to get fireworks in some states than others, the clear trend across the country has been toward greater liberalization in sale and use. Since 2000, 19 states have relaxed their fireworks laws, according to the American Pyrotechnics Association.

Growing up in Massachusetts — which, today, is the only state that completely bans all forms of fireworks, including sparklers — Zagorsky remembers a guy in his neighborhood who did brisk business selling them illegally out of the trunk of his car.

"He made a fortune during the 4th of July," Zagorsky says. "Basically the entire neighborhood showed up, like standing in line with cash in their hands, waiting to hand him money so that this illegal contraband could be bought for the week before 4th of July."

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But, Zagorsky says, many states and counties grew tired of their residents crossing jurisdictional lines to buy fireworks — and they realized they were losing out on potential revenue from these patriotic backyard explosions.

"If people are going to be doing these activities, and I just don't mean fireworks, many politicians say, 'Well, maybe we should profit a little bit off of it,'" Zagorsky says. "Maybe we can fund some of the key services we need to provide our citizens. So if people are gonna gamble, we may as well tax gambling. If people are going to illegally smoke marijuana, maybe we should tax that. It's the same thing for fireworks."

There remains a patchwork of laws restricting the use and sale of fireworks in many parts of the country, including in the West, where there are drought conditions and fire risk.

But, Zagorsky says, increased product safety and the seeming inevitability of these purchases across jurisdictional lines are why we've seen a general kaboom in fireworks liberalization across much of the nation. These laxer laws have helped fuel another kaboom in sales.

Data from the American Pyrotechnics Association finds that the consumer fireworks industry has seen its annual revenue grow from $407 million in 2000 to $2.3 billion in 2022. "Display fireworks" — think big fireworks events on July 4th put on by professionals — accounted for an additional $400 million in revenue.

The American Pyrotechnics Association also tracks estimates of the total weight of fireworks sold. In 1976, according to their numbers, Americans purchased 29 million pounds of fireworks. In 2022, we purchased 461.7 million pounds.

In addition to laxer regulations and increased product safety, Zagorsky says, the explosive growth in fireworks sales has also been fueled by cheaper products, thanks largely to productivity growth at factories in China, where most fireworks are made.

Injuries From Fireworks

With this explosion in firework sales, you might also expect there to be an explosion in injuries from fireworks.

The American Pyrotechnics Association claims that has not been the case. "During this period of unprecedented growth, fireworks injuries have declined dramatically due to industry safety education efforts and the ever improving quality of its products," the organization says in a release. "Over the most recent decade, this downward injury trend continues even as an increasing number of states & municipalities have relaxed their consumer fireworks laws — in fact the injury rate was almost 70% lower in 2022 compared to 2000."

But Zagorsky says injuries have, in fact, been creeping up in recent years. One study found that emergency room visits due to injuries attributed to fireworks increased from 5727 in 2008 to 7699 in 2017 — a 34% increase. The scholars found that most of the victims were male and — surprise, surprise — the vast majority of these accidents happened in July.

Likewise, the U.S. Consumer Product Safety Commission found that, between 2006 and 2021, there was a 25% increase in fireworks injuries. Last year, the agency recently announced, there were 10,200 injuries from fireworks and 11 deaths. The agency calculates that 73% of these accidents "occurred during the one month surrounding the July 4th holiday."

"We base our reports on data from emergency rooms around the country, and what we're seeing is that the number of deaths and injuries associated with fireworks remains high," says a spokesperson from the agency.

Julie Heckman, the executive director of the American Pyrotechnics Association, counters that "the CPSC and other groups don't consider the extreme increase in consumption." Once you consider that many more people are using fireworks these days, she argues, "the fireworks-related injury rate is the lowest ever recorded."

"In 1990, for every 2 million kilos of fireworks, we had one injury," Zagorsky says. "Today for every 2 million kilos, we have 0.2 injuries. So, basically, injuries over the last 30 years with fireworks — after adjusting for the explosive growth in fireworks — has fallen by a factor of five."

Interestingly, according to research from the National Fire Protection Agency, fires due to fireworks have also declined somewhat significantly in recent decades, even as firework sales have skyrocketed. Some of the safety regulations imposed over the years — which have, for instance, reduced the likelihood that fireworks tip over and have outlawed the most dangerous types of fireworks — may help explain why fire risks have declined.

At the same time, however, a recent report from the U.S. Consumer Product Safety Commission suggests that makers of fireworks are still skirting safety regulations. They find that "approximately 43 percent of selected and tested fireworks were found to contain illegal components that could cause severe injuries. These components include fuses that do not comply with the law, the presence of prohibited chemicals, and pyrotechnic materials overload."

Anyways, Happy Fourth of July. Enjoy the explosives. Please be careful, and don't get injured or start a fire using them.

An audio version of this story ran on The Indicator. Listen to it here