Impact of Energy-Based Safety Training on Quality of Prejob Safety Meetings and Control of Hazardous Energy in Construction: Multiple Baseline Experiment

This study explored the role of energy-based safety training on the quality of the prestart meetings.

Method was a multiple baseline assessment on 10 construction crews in the US and Canada following the training intervention, then measuring the prejob safety brief quality and HECA (High Energy Control Assessment).

Background:

· Construction accounts for about 7% of the global workforce but ~30% of fatalities

· Within US construction “fatality rates have plateaued over recent decades, in contrast with the rate of less serious injuries, which has since plummeted”

· “Although SIFs are more devastating than less serious injuries (LSIs), little is known about the differences in their proximal causes”

· Whereas “most injury prevention strategies have been designed to address all types of injuries without discrimination”, recent research has “revealed three proximal causes unique to SIFs: (1) the presence of high energy (i.e., hazards with over 1,500 J of physical energy); (2) absent direct controls for high-energy hazards; and (3) absent or inadequate prejob planning as it relates to the control of high-energy hazards”

· Common injury measures are also problematic, since they’re “based on events that are rare and randomly distributed over time, so millions of worker hours are required to obtain a meaningful statistical measure”

· And “over time, most organizations concurrently implement a portfolio of interventions, making it challenging to isolate the impact of a given intervention”

· “Although most studies demonstrate that some causal factors are present in all injuries regardless of severity, empirical evidence reveals different frequencies of these factors when comparing LSIs and SIFs”

· Differences include factors related to the work activities and equipment, demographics, work experience, injury parameters and location, energy source and magnitude

· Other work has found that “the effects of minor injuries on work absence can be as significant as the effects of more serious injuries”

· Bayona et al. “found three unique proximal causes of SIFs: the presence of high energy (i.e., over 1,500 J); a missing or inadequate prejob safety plan; and hazardous energy that is not adequately mitigated by physical barriers (i.e., absent direct controls)”

· “Although many human factors were studied (e.g., risk normalization, poor response to change, and poor hazard recognition), they were found to be present equally in both LSI and SIF cases”

· Several recent studies when evaluated collectively suggest that “SIF prevention requires a differentiated approach for safety interventions in which the key focus is on the planning for and the control of high-energy hazards”

· They talk about HECA and high-energy hazards, noting the importance of ways to identify, measure and learn about operational safety, where “injury rates—the prevailing measures of safety—are antithetical to this new philosophy” (emphasis added)

· Again on HECA, to qualify as a direct control for high energy hazards, safeguards must “be targeted to the high-energy hazard source; mitigate the energy to below the 1,500-J threshold; be installed, verified, and used properly; and remain effective even if there is an unintentional human error during work”

· [** Notably, other research/practice streams delineate barriers and safeguards as both controls, where barriers meet strict criteria—not dissimilar to a critical control—and safeguards are more performance shaping factors that contribute to barrier integrity but don’t meet the strict criteria to qualify as a barrier]

· Next they discuss how they assessed the quality of prestarts, which I’ve skipped

Results

Key findings:

· Training on energy-based methods “caused immediate and significant improvements in the quality of prejob safety briefs and a measurable but smaller effect on the HECA score”

· “Whereas prejob safety meeting scores and effect sizes were consistent, HECA was highly variable across the work crews both before and after the training”

· “This suggests that, although short-term impacts on the quality of safety planning may occur over a short time frame, the impacts on the control of hazardous energy may require comparatively more time and data to achieve conclusive results”

· “There was an average level-change improvement of 15.7% for the [prestart] quality score, and an average improvement in the HECA score of 6.1% following the intervention”

· Notably however, only the change in performance in HECA scores was statistically significant for two of the ten crews (at alpha of 0.05%, and one crew at 0.1 alpha)

Overall, the training intervention had a “Strong and Reliable Immediate Impact” on the prestart quality score. Further, unionised crews that received the training in English had more consistent changes in post-intervention prestart scores than did “open-shop crews that received the training in Spanish”.

The intervention was found to improve the way which crews plan for high-energy hazards. This also included changes in hazard communication.

Nevertheless, the HECA scores were less promising. They say their inability to detect statistically significant changes in the crew activities via HECA scores may relate to the small changes relative to single-crew sample sizes. Also, variations in data collection may make assessing HECA across the sample difficult, outside of larger samples.

They also argue that, “although they were not statistically significant, notable improvements were found for the presence of direct controls for electrical (arc flash), motion (swaying load), and gravity (overhead loads) hazards (150%, 116%, and 49%, respectively)”

Hence, “Overall, the evidence for improvements in HECA scores is mixed, and the true average effect of the intervention remains unclear”

Further, the training intervention, at least short-term (over 4 weeks), had a greater impact on worker behaviour than on improvements to the work environment. Hence, “SIF-focused training interventions cause immediate and significant improvements in the quality of PJSMs and the subsequent control of high-energy hazards”.

Ref: Bayona, A., Hallowell, M. R., Bhandari, S., Moyen, N., & Lien, A. (2025). Impact of Energy-Based Safety Training on Quality of Prejob Safety Meetings and Control of Hazardous Energy in Construction: Multiple Baseline Experiment. Journal of Construction Engineering and Management, 151(7), 04025086.