This video is from FusionNW and discusses Garage Door safety. First, the presenter disconnects the garage door from the lifting mechanism. He then moves the door up and down to check for balance and any rough areas. Next, the presenter moves on to test the reversing mechanism. Place a 2x4 underneath the door and lower the garage door. If the mechanism is working correctly, the door will reverse and raise up after it hits the board. You will then want to test the sensitivity of the reversing mechanism. Place your arms under the door as it is lowered and applying increasing force until the door reverses.