Truss failure - video

[IAMSatisfied]

I'm glad this fellow stepped out of the way in time to save his brains. One of the dangers of working alone (and in an unsafe manner) is that if you make a mistake, it can be costly. I wouldn't want my wife (or anyone) to find my lifeless body, especially due to a very avoidable catastrophe.

Unlike how this fellow is doing it, typically you start setting trusses at the gable end (assuming your building has a gable end, and not a hip roof). That first gable truss is diagonally braced plumb and fastened securely. Once that's done, a person working alone can attach a small block/pulley to the peak of that first truss and use a weight on a rope to assist in lifting and retaining the subsequent truss in place until you can get up there to secure it. From the camera angle, I see no diagonal bracing on his first truss, which looks downright scary.