Abstract: At 3:30 p.m. on December 5, 2018, Employee #1 and Coworkers #1 and #2, employed by a residential construction company, were engaged in building a new two-story wood-frame single-family residence. Employee #1 and Coworker #1 were in the basement space to set and block joists that would be the ceiling for the basement and the floor for the house's primary living area. Coworker #2, the Lead Carpenter, was in the basement and had just removed a ledger that was supporting five joists that were not set on an existing top plate or other supporting structure. Coworker #2 verbally instructed Coworker #1 to avoid the five unsupported joists. Employee #1, who was approximately 50 feet away, did not hear the instruction. Coworker #1 left the work area to cut a joist. Coworker #2 left the work area to get more hangers for the unsupported joists. Within approximately two minutes, Employee #1 returned to the work area and walked onto the unsupported/unbraced joists. The joists gave way, and Employee #1 fell, first becoming entangled in a brace during the fall and then striking the concrete surface and a timber slab laying on the concrete, for a total fall height of approximately 10.5 feet. Emergency services transported Employee #1 to the hospital. He was admitted and treated for multiple fractured ribs and a fractured lower leg (fibula).