Nails guns can be helpful when it comes to carpentry, but they can also be deadly. A construction worker in Peshtigo, Wisconsin, accidentally shot a nail into his heart after working on a fireplace for a home. Doug Bergeson, 52, drove 12 miles to the emergency room at Bay Area Medical Center where doctors performed surgery to remove the 3.5-inch nail in his chest.

"It didn't really hurt. It just felt like it kind of stung me. And I looked down and I didn't see anything and I put my hand there and... That's not good," Bergeson told WBAY, an ABC affiliate.

Upon arriving at the hospital, after some tests and a tetanus shot, Bergeson was brought to BayCare Aurora Medical Center in Green Bay, where he underwent open-heart surgery. During the approximately 1.5-hour surgery, doctors removed the nail and made sure the surrounding areas were not damaged. The nail missed Bergeson's main artery in his heart by a margin about the thickness of a piece of paper.

Dr. Alexander Roitstein, a cardiothoracic surgeon at BayCare Clinic who performed the surgery, admits Bergeson was extremely fortunate. If the nail had made contact with an artery, it would have caused internal bleeding and the heart to stop pumping blood in two to three minutes.

"A wrong heart beat, a wrong position and he would have had a much more complicated problem than he was bargaining for," said Roitstein.

Nail guns are powerful tools that are responsible for an estimated 37,000 emergency room visits each year, according to the Centers for Disease Control and Prevention. People who use these tools may face injury or death from double-firing, or from wielding the tool while in an unusual body position, like in Bergeson's case. The 3.5-inch nail fired straight into his heart with the speed of a .22 bullet.

Bergeson previously told The Washington Post he had to reach up while standing on his tiptoes, wrap his left arm around and behind the wood frame, in a way that the gun would face his body when he pulled the trigger with only the wood acting as a barrier. However, the gun accidentally double-fired two nails in quick succession, rather than just one. It was the second nail that pierced into his chest.

Nail guns have been at the root of freak accidents, including one in December last year, where Nick Thompson, a Minnesota home builder, accidentally fired a nail gun into his head while framing a closet, Fox 9 reported. Thompson believed he must have a hit a nail already in the wood, which led the nail gun to kick back into his face. He arrived to the hospital unaware that a nail was lodged in his eye as he was rushed into emergency surgery. Surgeons were able to remove the nail without Thompson losing sight in his eye or injuring his brain.

Those who work in construction can reduce their risk of nail gun injuries by switching to using only sequential triggers. After a series of many double fires and a related serious nail gun injury in his crews, a New Jersey contractor started to use sequential triggers, which he estimates has only had a slight impact on productivity — a few extra hours per house.

Following nail gun safety protocol can prevent injuries from occurring and keep construction workers and consumers safe.