Automatic garage doors are a serious safety hazard if they're not installed or maintained properly — especially if they were installed before 1993, when safety standards were improved. Since then, automatic garage doors are required to have an external entrapment protection system (an electric eye, a door edge sensor, or any other device that senses when it comes into contact with something, and immediately reverses the door), or a constant contact control button, which requires you to hold the open/close button all the time that the door is in motion.

If your older garage door does not have an automatic-reverse function, replace it, or retrofit it with a new opener that will reverse. Garage doors are heavy enough that they can seriously injure or even kill a child who gets caught under them.

Even newer garage doors need monthly checks to ensure that their safety measures are working properly. The first check is that the door is balanced-that it will stay in place wherever it's stopped. First, detach the garage door opener from the closed door (there should be a quick-release lever). Open and close the door manually. It should move smoothly, without binding or sticking, and should stay open if you let go of it about 3 to 4 feet above the ground.

To check that the door will automatically reverse, place a 2″ × 4″ on the ground below the open door and use the automatic controls to close the door. The door should reverse as soon as it touches the 2″ × 4″. If it doesn't, look for an automatic reversal knob or screw on the power unit, and adjust it until the door reverses properly (check the instruction manual for the exact location and operation).

To test the door's force, hold the bottom of the door as it automatically closes. Again, the door should immediately reverse. If it doesn't, there should be a force adjustment control knob or screw on the power unit (again, check the instruction manual). You'll probably need to open and close the garage door again before retesting it.

Additional safety precautions include warning children to stay clear of garage doors, keeping remote controls away from children, and locating the garage door switch 5 feet off the ground (out of their reach). You should also examine the door's mechanisms, including springs and cables, to check for signs of wear or aging (these items are under high tension, so be careful, and call a qualified professional for repairs). Your garage door instruction manual should also include safety measures. If you need a copy of the manual, call the door's manufacturer or installation company (the model number should be on the power unit).