Injuries from the nail gun account for some 37,000 trips to the emergency room each year. The tool can sink thousands of nails a day consistently, accurately and safely when used correctly. However, as so many workers find out the hard way, little mistakes can lead to big problems.

Bump-firing a nail gun, or keeping the trigger pulled to rapid-fire nails by bouncing the gun’s safety tip along the nailing surface, can lead to an accidental shot. While bump-firing certainly speeds things up, a much safer choice is using a gun with a sequential trigger that must be pulled for every shot. The risk of an injury is twice as high when bump-firing a nail gun as when using one with a sequential trigger.

Since the nail gun is a one-handed tool, there is tendency to focus completely on the firing hand while ignoring the other. Too often, this leads to accidently shooting the passive hand. Always be conscious of both hands, keeping a firm grip on the tool with one hand and keeping the other at least 12 inches away from the gun.

Make sure you have plenty of room for recoil. An accidental “double shot” can happen if your elbow or gun bounces off an object during recoil, throwing the gun down for an uncontrolled firing. If the spot is too tight for a nail gun, opt for a hammer.

Don’t assume the nail will go where intended. It can glance off the side of a stud, fly through an unseen knot or miss a stud completely if shooting through sheathing. So make sure all coworkers are well out of the line of fire.

While it feels natural to carry the gun with your finger on the trigger, an unexpected bump can depress the safety and fire a nail. Bump it against your leg and you may acquire an unwanted hamstring piercing.