Fireworks are a big part of Finnish New Year's Eve celebrations. Unfortunately the explosives do cause injuries yearly: last year fireworks hospitalised 17 people for eye injuries. However, the number of injuries has gone down compared with New Year 2009-2010, when a total of 47 people badly hurt their eyes.
"There are four main groups of eye injury. Ruptures are thankfully rare now that protective glasses are being used. We used to get a few of them every year 15 years ago," says professor Tero Kivelä from the Department of Eye Diseases in Helsinki.
Three of the most common forms of eye damage caused by fireworks are contusions, superficial burns and foreign objects such as gunpowder in the eye.
"The injuries are usually restricted to just one eye. It's possible to go blind in just one eye, we get a case or two like that every few years," Kivelä says.
Protective eyewear use has helped bring down cases of ruptured eyeballs as well as other forms of physical harm.
"The safety glasses should definitely be worn, and the law says that the person lighting the firework must do so," Kivelä says. "Onlookers aren't law-bound to wear them, but everyone observing fireworks really should – or watch from behind a window."
The new legislation on protective eyewear came into effect in January, 2010. The same law also forbade small Roman candles and mini rockets, shortened the permissable firing period and made it illegal for under 18-year-olds to have fireworks.
Kivelä says that another thing that protects from bodily harm in addition to the glasses is a sensible safety distance – but even that is not as safe as wearing goggles, as rockets may misfire.
Those most at risk are children and, perhaps surprisingly, men. Kivelä says he cannot recall when he last encountered an eye injury in a woman who had sustained it when lighting a New Year's rocket.