In spite of the efforts by government agencies, labor organizations, and researchers in the field of health and safety, injuries and fatalities continue to affect the construction industry. In 2002, the construction industry had the undesirable distinction of having two of the most dangerous occupations in the United States, with fatalities among structural steel workers at 58.2 fatalities per 100,000 workers (4 th highest rate) and construction laborers experiencing fatalities at the rate of 27.7 fatalities per 100,000 workers (9 th highest rate) (Bureau of Labor Statistics, 2002). In addition to the costs associated with construction accidents such as increased insurance premiums and medical expenses, loss of productivity is a cause for concern to the industry. For example, when a worker is injured, his/her productivity can decrease by 33% during the first 48 hours following the occurrence of the injury (Coble et al. 2000). It has not been proven how unsafe working conditions affect worker productivity, and the impact of unsafe work practices on worker performance has not been quantified. Many workers in the construction industry