Accident; analysis and prevention
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For many years, to reduce the crash frequency and severity at high-speed signalized intersections, warning flashers have been used to alert drivers of potential traffic-signal changes. Recently, more aggressive countermeasures at such intersections include a speed-limit reduction in addition to warning flashers. While such speed-control strategies have the potential to further improve the crash-mitigation effectiveness of warning flashers, a rigorous statistical analysis of crash data from such intersections has not been undertaken to date. ⋯ It is speculated that, in the presence of potentially heterogeneous driver responses to decreased speed limits, the smaller distances covered during reaction time at lower speeds (allowing a higher likelihood of crash avoidance) and the reduced energy of crashes associated with lower speed limits are not necessarily sufficient to unambiguously decrease the frequency and severity of crashes when the speed-limit reduction is just 5 mi/h. However, they are sufficient to unambiguously decrease the frequency and severity of crashes when the speed-limit reduction is 10 mi/h. Based on this research, speed-limit reductions in conjunction with signal-warning flashers appear to be an effective safety countermeasure, but only clearly so if the speed-limit reduction is at least 10 mi/h.
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Randomized Controlled Trial
Are what happens next exercises and self-generated commentaries useful additions to hazard perception training for novice drivers?
We investigated whether self-generated commentaries and what happens next exercises are useful additions to hazard perception training. Two hundred and thirty-three novice drivers experienced one of four different video-based training interventions derived from an existing hazard perception training package: (1) what happens next training; (2) expert commentary training; (3) hybrid commentary training (i.e., expert plus self-generated commentaries); or (4) the full training package (i.e., what happens next plus hybrid commentary training). There was also a placebo control condition. ⋯ All training effects decayed significantly after the delay, but the effect of full training remained significant. Although no benefit was found in adding self-generated commentaries to expert commentaries, the possibility remains that the what happens next exercises may provide an additional benefit when combined with commentary training. The results provide further support for hazard perception training as an evidence-based alternative to traditional methods of improving novice driver safety.
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There are four primary accident types at steel building construction (SC) projects: falls (tumbles), object falls, object collapse, and electrocution. Several systematic safety risk assessment approaches, such as fault tree analysis (FTA) and failure mode and effect criticality analysis (FMECA), have been used to evaluate safety risks at SC projects. However, these traditional methods ineffectively address dependencies among safety factors at various levels that fail to provide early warnings to prevent occupational accidents. ⋯ The ranks of posterior probabilities from the BN model were highly consistent with the accidents that occurred at each project site. The model accurately provides site safety-management abilities by calculating the probabilities of safety risks and further analyzing the causes of accidents based on their relationships in BNs. In practice, based on the analysis of accident risks and significant safety factors, proper preventive safety management strategies can be established to reduce the occurrence of accidents on SC sites.