Good advice on this site. I just went out into our garage to take the car over for an oil change. When I hit the button for the garage door to open it the spring broke and it came crashing down. A garage door weighs 300 - 400 pounds so if I had been under it I would have been killed. A small child would certainly be killed. Just letting you know this happened so you can be careful. The thing was just a few feet away from me and believe me it scared the you-know-what out of me.
The link below has some really good tips about garage door safety.
State Farm Insurance Garage Door Safety