| In the construction industry, safety performance has historically been measured with lagging indicators of safety performance such as recordable injury rates (RIR); days away restricted work, or transfer (DART) rates; or experience modification ratings (EMR). These metrics are lagging indicators because they are linked to after-the-fact assessments of safety performance. Alternatively, leading indicators are metrics that are linked to actions taken to prevent accidents and to predict future safety performance. Leading indicators are classified as passive (i.e., the strategies implemented prior to the construction phase) and active (i.e., measures of safety controls that can be measured during construction). The present research aims to identify passive leading indicators that most effectively predict safety performance. Initial efforts to identify passive leading indicators were directed to the findings of past construction safety studies. Brainstorming sessions and focus group discussions were also held with an expert panel to identify potential passive leading indicators. The relative impacts of these metrics were quantified using statistical analyses of empirical data obtained from interviews conducted with representatives from 57 projects. Of the 104 potential leading indicators, 74 were implemented on more than 80 percent of the projects. Of the remaining 30 indicators, Wilcoxon Rank Sum tests showed that 10 of the practices were associated with lower injury rates (p-value < 0.05). When combined, the implementation of these strategies is inversely related to project RIR, with an average reduction of 0.42 injuries per 200,000 worker-hours per indicator implemented (R-squared = 0.98; p-value = 0.01). The results can be used by practicing professionals to measure safety potential before a project begins and to better plan safety management activities. |
