Abstract: On Monday, July 31, 2000, Employee #1 was on a crew that was straightening some wooden roof trusses that had been installed on a 72 ft by 60 ft building on the previous Friday, July 28, 2000. When the trusses were installed, they had not been braced correctly. The company had used 3 ft T-blocks and only had installed diagonal bracing on the north end of the building. As a result, the wooden roof trusses bowed over the weekend. In an attempt to correct the problem, the crew used a rope attached to a farm tractor at the front of the building and a chain attached to a small Bobcat loader at the back of the building to apply tension to the trusses. When this failed to completely straighten the trusses, Employee #1 was sent to the top plate to unsecure, straighten, and re-secure one truss at a time. He had unsecured the first truss when the release of the tension created by the tractors on the ground resulted in a spring-like effect, causing the wooden roof trusses to collapse like dominoes. Employee #1 was knocked 16 ft to the ground, sustaining numerous minor injuries to his torso, arms, and legs. He was flown to the hospital, where he was treated and released.