ATLANTA, Georgia (CNN) -- The scar has faded over his left eye, but the fireworks injury that Tony Wittmann suffered when he was 17 taught him a lesson that he hasn't forgotten.
Sparklers burn at temperatures up to 2,000 degrees Fahrenheit (about 1,100 Celsius).
"Teenagers being teenagers, we were shooting bottle rockets at each other from about 200 yards away," he remembers. "One hit above my eye and stuck in my forehead and exploded."
Emergency room doctors were able to stitch up the torn the tissue around his eye, but Wittmann was pretty shaken up. "I thought at first, 'I'm 17 and I'm blinded for life.' Once I calmed down, I realized I was OK, but it took all the fun out of the day."
Wittmann, now a 42-year-old firefighter and paramedic in Shawnee, Oklahoma, uses the story to explain the dangers of fireworks to his young sons. "I try to tell them to learn from my mistake."
Every year at this time, he and his colleagues expect to be sent on a fireworks emergency call. "Either a roof will be set on fire or someone will get burned," he said. "I don't think you'll ever get an injury-free season." Health Minute: Watch more the dangers of fireworks »
Unfortunately, that's true not just in Oklahoma, but in the rest of the United States as well.
The Consumer Product Safety Commission keeps track of injury rates nationwide. Nancy Nord, the commission's acting chairwoman, says fireworks injuries are common. "Over 9,000 people are injured each year because of fireworks, on average seven people die," she said.
The agency estimates that half the injuries occur among children. "Little kids love sparklers," Nord says. "But sparklers burn at temperatures up to 2,000 degrees [Fahrenheit], and sparklers are the biggest cause of injury for children under 5."
Burns, lacerations and eye injuries are some of the most common injuries reported.
Despite the risks, fireworks are more popular than ever. Bill Weimer, vice president of Phantom Fireworks in Youngstown, Ohio, says this is the busiest time of the year for sales.
His company is the operator of the largest chain of fireworks stores in the country and expects to make 95 percent of its yearly sales between Memorial Day and July 4. Three years ago, The Wall Street Journal estimated the six-week revenue to amount to $100 million, a figure Weimer doesn't dispute.
But along with increased profits, he contends, "Fireworks products are safer today than ever before. Most of the injuries unfortunately are due to misuse and abuse."
He strongly encourages people to read the directions and follow the rules. "This product is wonderful family entertainment, but at the same time, you have to respect the fact that [fireworks] burn to function. ...Parents should watch their kids like hawks."
That's part of the No. 1 safety tip from the Consumer Product Safety Commission: Never allow children to play with or ignite fireworks. The commission also warns users to keep a bucket of water or hose nearby in case of fire, to light fireworks only on a flat surface away from structures and dry leaves, and not to relight fireworks that have not fully functioned.
Experts also tell bystanders to be out of range before lighting fireworks. It's a rule Wittmann learned the hard way. "People don't understand you're dealing with explosives. Most people take them for granted. I know I did." E-mail to a friend
Judy Fortin is a correspondent with CNN Medical News.