Abstract: At approximately 8:00 a.m. on December 10, 2007, Employee #1, a journeyman carpenter with Brutoco Engineering & Construction, Inc., was at the site of an underpass inder construction below a railroad bridge in El Monte, CA. He was standing on the third whaler of the wood formwork of a retaining wall support system, installing some reinforcing bars. Employee #1 was climbing down to the fourth whaler when he lost his footing and fell 15 ft to the ground, fracturing his right leg. He was tied off while on the third whaler, but unhooked his fall protection while repositioning on the fourth whaler. Employee #1 later stated that this was a common practice, to unhook fall protection while transitioning from one spot to another spot of vertical formwork, and that his coworkers did it as well. He also stated that no catenary line or lines had been installed there for sliding hooked attachments.