| Despite continual efforts to improve safety performance, the construction industry continues to account for a disproportionate number of occupational injuries. Apart from long-term physical and emotional distress to workers and their families, these injuries have a devastating economic impact on the sustainability of the industry. One of the reasons that injury rates remain high is that workers are sometimes unable to recognize and respond to every hazard that is encountered in dynamic work environments. This research seeks to transform safety performance by empirically testing the efficacy of three innovative hazard recognition strategies that are specifically tailored to the construction industry. Specifically, this study (1) identified promising proactive hazard recognition strategies being implemented in various industries; (2) identified what industry experts believe are the three most promising strategies based on established decision criterion; (3) developed and refined the strategies and associated implementation tools; and (4) field tested and analyzed the strategies with active crews to measure performance and response in real-life scenarios using the multiple baseline testing technique and interrupted time series regression analyses techniques.;This dissertation provides a rationale for conducting studies to improve the hazard recognition levels, provides details on the designed strategies, details the multiple baseline based field testing approach, and discusses the analyses techniques and research findings. In the first phase, promising strategies were identified through an extensive literature search, review of construction safety documentation and a panel of 12 domain experts. Subsequently, a down-selection process based on pre-established implementation attribute criterion and group consensus from the expert panel was conducted to identify the three most promising strategies that may feasibly be tested on active crews. The three strategy elements that emerged as being potential and testable were (1) the pre-job safety meeting quality measurement (SMQM) maturity model, (2) a System for Augmented Virtuality Environment Safety (SAVES) program, and the (3) visual cue based Hazard Identification and Transmission (HIT) board. These chosen hazard identification strategies, in the second phase, were then further developed through brainstorming sessions with the expert panel and through questionnaire surveys. In the third phase, six independent empirical multiple baseline longitudinal studies was conducted with three active work-crews to test the effects of introducing the devised strategies on dynamic construction environments. The multiple baseline study results were used to test the null hypothesis that: the intervention does not improve the proportion of hazard identified and controlled in dynamic construction projects using interrupted time series regression analyses.;Our field study with SAVES as the intervention indicated that the crews on average were able to only identify 46% of hazards prior to the introduction of the intervention, but were able to recognize 77% of hazards in the post-intervention phase (p < 0.01).;Similarly in the sites that the SMQM intervention were tested, the workers were only able to identify and communicate an average of 38% of hazards before the intervention was applied, but the new strategy caused a weighted overall level-change improvement in hazard recognition skill of 31% (p < 0.01). Therefore, at the end of the study, the workers recognized 69% of hazards.;For the HIT intervention, The results indicated that the crews were able to recognize and communicate only an average of 54% of hazards in the baseline phase, but were able to recognize 77% during the planning phase after using the intervention (p < 0.01). An additional 6% of hazards were identified in the execution phase (p < 0.01). Therefore, 82% of hazards were identified after introducing the HIT board.;The primary contribution of this research is the development and the evaluation of highly effective hazard recognition programs to facilitate and stimulate improved safety performance in the construction industry. The results of this study make valuable contributions to the construction industry by proposing proven techniques for improved safety performance, if adopted. |
