Abstract: Employee #1, a supervisor hired by a religious ministry to oversee a project, was climbing a Keller extension ladder, model 5128, serial #068136810, to refocus a newly installed video projector. The ladder had been set up by a church volunteer and was being held at the base by another coworker. Employee #1 ascended and as he approached the area where the two ladder sections overlapped, the upper section started to slip. As the section slid, it disengaged itself from the 8 in. purlin against which it was propped and started telescoping downward as well. Employee #1's foot became caught between a rung of the upper section and a rung of the lower section and was fractured. The ladder had a maximum rating of 300 lb and a maximum extended length of 25 ft. The locking mechanism on the extended ladder was not secured.