Abstract: Employee #1 and a coworker were working on the second floor of a residential home, preparing to install spiral stairs. They installed a diagonal laminated beam which spanned across the northeast corner and began to install the 2-inch by 10-inch joists between the north edge of the second floor foyer and the laminated beam. The first joist, 8.5 inches long, was installed and nailed into place. The second joist, 24.5 inches long, was set in place but not nailed by Employee #1 who was kneeling on the north side edge of the foyer. The coworker, kneeling on the east side edge of the foyer, was setting the third joist, 40.25 inches long, and asked for Employee #1's assistance. Employee #1 held the north edge of the 2-inch by 10-inch joist while the coworker nailed the south side against the laminated beam. After the coworker nailed the south side of the joist, Employee #1 let go of the north side edge which caused it to drop down. While trying to retrieve the end of the joist, Employee #1 leaned down and used his right hand to brace himself on a second 24.5-inch-long unsecured joist. The joist fell causing Employee #1 to fall forward through the space between the north side edge of the foyer and the laminated beam. He did a somersault and landed on his back against the laminated floor beam running in a north-south direction separating two floor holes on the first floor. He then flipped forward and fell face first onto the basement floor. Employee #1 was transported by helicopter to Hartford Hospital where he was hospitalized.