Abstract: At approximately 2:00 p.m. on September 27, 2008, Employee #1 was working as a chief stationary engineer for a property management company. The original exterior building maintenance unit for one of their buildings, was manufactured by Spider Staging Sales Company in 1981. It consisted of a two-line, self-powered platform, suspended from a pair of mobile trolley davits. The mobile davits were used in conjunction with a track-mounted roof car. In 2007, the equipment was upgraded to a four-wire, roof-powered platform by TRACTEL, LTD. The modification of the equipment included replacing the two control panels with one control panel. The upgraded unit was put into service and used for window cleaning in mid August 2008. On September 27, 2008, the two-man suspended platform was operated by a coworker who worked for the window washing contractor, and Employee #1 assisted him. The work was completed and the platform was raised to the roof top. The platform was shaking and Employee #1 grabbed the davit boom by placing his left hand next to the unguarded trolley wheels. The coworker, who was at the control panel, activated the trolley to boom in the platform and bring it to the stored position. The trolley wheels rolled over Employee #1's small finger, amputating it.