America, heck yeah! (Tim Kelley)

This is the time of year when we celebrate the independence of our nation by blowing up a small part of it. It is fireworks season.

We will leave to others (interns, probably) the task of trudging through the crowded, putrid swamp of the National Mall on Thursday to bring you live reports from the biggest fireworks display in the nation's capital. But here at Wonkblog, we can offer you the crucial facts you need to know before basking in the rockets’ red glare. Which when Francis Scott Key wrote the song lyrics was really a reference to actual explosives in the Battle of 1812, but which seems apt for the pyrotechnics associated with America’s patriotic celebrations of today.

You might injure yourself. You probably won’t kill yourself. The Consumer Product Safety Commission found that in 2012, there were 8,700 injuries in the United States caused by fireworks that required treatment at a hospital, well within the recent range of injury numbers (the 15-year high was 11,000 in 2000, the recent low 7,000 in 2008). But there were only six deaths reported in 2012, four in 2011, and three in 2010. (Here is more from Sarah Kliff on where on the body those injuries are likely to occur)

The injury rate seems to be falling over time. The injury rate per 100,000 Americans averaged 3.3 from 1997 to 2002. In the five years ended in 2012, it averaged 2.8. It's possible that this can be chalked up to random chance; injury numbers from year to year are volatile. Other measures of the rate of injury paint an even clearer picture. Injuries per 100,000 pounds of fireworks imported averaged 6.9 in the 1997 to 2002 period, which was down to 4.1 from 2007 to 2012.

More fireworks injuries are suffered by men. This will surprise no one who has seen an adolescent boy play with fire, or watched the Tosh.0 show. But males of the species are significantly more likely to make the  . . . questionable decisions that lead to injuries from pyrotechnics. Men and boys accounted for 74 percent of injuries in 2012. The damage was concentrated among younger men: Males between the ages of 15 and 24 account for 7 percent of the U.S. population, but 23 percent of the fireworks injuries.

Much of the world’s firework production is in this one city in China. Liuyang, in the Hunan Province, has a population estimated at 1.3 million and is the world’s fireworks production powerhouse. Reliable data on how much of the world supply it produces are hard to find; various reports have stated that it accounts for large percentages of global output, but usually without citing a source. (Here is a nice travelogue from a CNN reporter’s visit to the city, and an L.A. Times article about Liuyang).

What is abundantly clear is that the city has many of what economists call agglomeration effects: Lots of different specialists in the various chemicals, papers and explosives needed to make fireworks, combined with a skilled workforce, all concentrated in one place. Here for example, is a first-person account of an American fireworks importer who set up shop in Liuyang. “To support these factories, Liuyang also has supporting manufacturing such as paper mills, chemical processing, fuse factories, printing factories, and a highly skilled fireworks workforce," he writes. "This critical mass of factors makes Liuyang the most economical place on earth to manufacture fireworks."

Oh, and they definitely test the merchandise: “On any given evening in Liuyang, the booms and bangs of customer demonstrations can be heard across the city,” the executive of Dominator Fireworks writes. “Need to test a few Roman Candles before your flight back to the USA, no problem, just stop on the side of the road and light them up!”

Fireworks safety laws can really interfere with your anti-War on Christmas campaign. Missouri State Rep. Rick Brattin (R) introduced, and the Missouri legislature passed, a bill to prevent what some conservatives view as a “War on Christmas.” It held that “No state or local governmental entity, public building, public park, public school, or public setting or place shall ban or otherwise restrict the practice, mention, celebration, or discussion of any federal holiday.” Democratic Gov. Jay Nixon vetoed it, however, writing that “it does not contain a public safety exception,” and thus that “local governments would be hampered in their efforts to enforce existing fireworks ordinances around July 4th.”