We’ve been mulling over some numbers lately, and they more or less come down to this: More and less.

We’re talking about fireworks. The American Pyrotechnics Association, an industry trade group, tracks injuries relative to sales. While use of fireworks doubled from 1997 to 2007, injuries per 100,000 pounds dropped 40 percent.

That’s good news, of course, but it doesn’t mean much to the 9,800 people who ended up in emergency rooms in 2007 because of fireworks, and it means even less to the 11 people who died.

As we close in on the Fourth of July holiday, when fireworks injuries peak, it’s a good idea to know both the laws for your state (five states ban all consumer fireworks; five more allow only sparklers) )
and the best ways to stay safe around all those incendiary devices.

We wondered whether there’s any way to tell whether one rocket is safer than another. So we called the American Fireworks Standards Laboratory, which tests about 85 percent of consumer fireworks sold in the U.S. (Yes, really tests; they pull samples from cases of product manufactured by their member companies and set them off in a lab in China.)

Products that meet safety standards get a certification sticker. The problem is you’ll never see it, because it goes on the shipping carton, not the retail packaging. So AFSL recommends you make sure that any fireworks you buy are from one of their members.