Construction safety by design: Struck-by accidents from an ergonomics perspective.

Introduction

Struck-by accidents are one of the more frequently occurring in the construction

sector globally and locally. Based on Federated Employers Mutual Assurance

Company (FEM) 2022 statistics, there were 1968 reported struck-by accidents.

This makes struck-by accidents the leading accident type in this period for

FEM policy holders, which, according to FEM makes up approximately half

of the formal construction workforce in South Africa. While struck-by accidents

have dropped compared to the previous year, it is still substantial given that

the second highest number of reported incidents were 906 slip or over-exertion injuries.

The concern with struck-by accidents is not only the sheer volume of them, but the

fact that they account for over a third of worker injuries that occur. There is thus

a pressing need to effectively identify and manage the risks associated

with struck-by accidents.

While construction organisations may investigate struck-by accidents to

determine the contributory factors, the fact that these seem to recur suggests

that either the contributory factors are not effectively identified during the

investigations, or that suitable controls are yet to be developed, implemented,

or maintained. This article will draw on ergonomics approaches and

propose a systems-based approach to understanding the contributory

factors to struck-by accidents.

(Under)Reporting and scope of reportable struck-by accidents

While struck-by accidents were the highest reported accidents according to

FEM statistics of the formal construction sector, it is likely that this number

is not a true reflection of the actual number of struck-by incidents that

occur. By definition, struck-by incidents include the following (CPWR, 2018):

• being struck by an object,
• struck against an object,
• caught in or compressed by equipment or objects,
• caught in or crushed by collapsing materials, and
• being struck by a motor vehicle while working next to a public road

The high number of struck-by accidents suggests that a lot of construction organisations do report struck-by accidents. However, the categories of events that are included in struck-by incidents as listed above notably exclude near misses where mobile objects in construction workplaces could potentially have caused harm but did not. Near miss incidents provide critical information on the factors that led to the near miss as well as the extent to which existing controls were able to prevent the incident. As such, while no visible harm may ensue, near-miss incidents provide valuable insights into what may need to be done to prevent a struck-by incident that may cause harm.

As such, it seems that the reported incidents are predominantly those where construction workers were injured and those that may have required compensation-related support. Consequently, it is likely that the bulk of struck-by incidents are not reported to FEM or other safety oversight bodies by employers. It is also possible that workers may not be reporting all the near misses of struck-by accidents or even actual struck-by accidents if they do not cause immediate or visible harm. This means that an investigation into all the causal factors is not always done. It also means that employers and other construction stakeholders may not have a comprehensive understanding of the underlying factors that cause the different types of struck-by accidents and the effectiveness of existing controls under different circumstances.

Construction employers and employees need to be educated and encouraged to report and investigate all struck-by incidents. Safety oversight authorities, including FEM whose policies influence the type of reportable incidents that construction employers report, should also consider including near-miss incidents in the categories of reportable incidents. They should also find more effective ways of encouraging the reporting of all incidents, and not only those where injuries occur or compensation is required.

This would also necessitate a review of safety performance incentives such as the FEM rebate program and the zero accidents campaign. Research suggests that safety incentives set the tone for what construction organisations monitor and report. As with other industries where health and safety metrics take centre stage in monitoring safety in organisations, under-reporting may be a factor that may diminish the number of reported struck-by incidents. Moreover, the rebate system may inadvertently incentivise the under-reporting of less serious struck-by incidents in order to improve the likelihood of receiving a rebate. The absence of accurate comprehensive data about struck-by incidents may inhibit the development of an industry-wide strategy for reducing this category of construction incidents.

Struck-by accidents as a product of sub-optimal system design: Safe systems support safe worker behaviour

From an ergonomics perspective, negative system outcomes such as accidents, injuries, poor quality, and lack of productivity are understood to be created by sub-optimal conditions within the system (Wilson, 2012). If we view struck-by accidents from this premise, and contrary to the conclusion drawn in many struck-by accident investigation reports, we can deduce that sub-optimal interactions with tasks, tools/ equipment, working environments, and organisational factors create conditions that are conducive for struck-by accidents to occur. These ergonomics-related deficiencies are found across the entire work system and are linked to ineffective integration ergonomics principles and an inability to match work demands to the capabilities and limitations of users and systems across the life cycle stages of a construction organisation or project. As such, understanding where sub-optimal working conditions come from necessitates a reflection of how each construction organisation or project may have inadvertently introduced conditions that did not match the capabilities and limitations of users and the overall work system.

While workers may be most proximal to struck-by accidents, it does not mean that they cause them. Apportioning blame to workers without considering the context or conditions that they were in when the accident occurred leads to a myopic understanding of the factors that contributed to the accident. It is thus recommended that, in place of the (reluctant) acceptance of construction accidents being a norm, construction accident investigations should be used as a way of identifying the systemic factors that contribute to accidents. Once these systemic factors are identified, the relevant controls, which would need to address the systemic deficiencies, would need to be implemented. Indeed, a review of several construction accidents reveals ergonomics-related risks that could be traced back to distal factors related to the tasks, tools, and organisational factors. The implementation of ergonomics in construction organisations, and projects in South Africa is arguably very low. Audits and reviews done on organisations reveal that ergonomic risks are prevalent in all workplaces, but these are typically not always identified or managed at all stages of organisational and project life cycle phases.

Some of the controls that are normally proposed to prevent struck-by accidents typically rely on changing worker behaviour instead of also finding ways that the system can be redesigned to prevent or minimise the risk of the accidents occurring. For example, the CDC provides a list of worker-focused best practices to reduce the risk of struck-by injuries due to equipment and falling or flying objects which includes the following:

• Worker training on safely operating equipment and the need to inspect tools and equipment
• Workers wearing protective personal equipment (safety glasses, hard hats, face shields, etc.).
• Workers exercising caution when working near heavy equipment.
• Workers ensuring that they do not work under a load during lifting operations.
• Workers needing to secure loads and lift evenly to prevent slipping.

Similar worker-centric controls are proposed and implemented in the South African construction industry. The high number of struck-by accidents suggests that the controls that are in place are not effective in a lot of cases. While these worker-focused behavioural change-dependent controls may assist to a certain extent, they do not target the cause of objects falling and striking workers. Moreover, interventions such as training and other worker-dependent controls are recommended as a last resort and should be used sparingly (Cox, 2020). The strategy adopted seems to be to accept the risk that objects will fall, as opposed to finding ways in which this can be prevented in the first place. In other words, construction workplaces seem to not be designed to fail-to-safe. Instead, they rely on workers protecting themselves when objects inevitably do fall. It is a commonly accepted practice to design equipment that has specific fail-to-safe functions or mechanisms as this is regarded as the most effective strategy for reducing risks (Wilson, 2012; Cox, 2020). This thinking is arguably not adopted in construction work systems, particularly in the management of struck-by accidents, which renders construction workplaces inherently unsafe in this respect. Through the integration of ergonomics principles in the design of construction work systems, and due consideration of optimising interactions between workers and system elements, more effective controls may be developed.

Conclusion

It is no secret that the construction sector is regarded as one of the most dangerous industries to work in. The statistics supporting this notoriety suggest that construction workplaces are more prone to causing harm to workers compared to some of the other safety-critical or high-reliability industries, and the struck-by accident statistics are but one of the many ills that plague this industry. Despite many interventions that are in place including legislation, safety training for workers, and the introduction of more advanced technologies, construction work systems remain unsafe. Perhaps it is time to integrate ergonomics and use systems-based approaches to assist the industry to get a more comprehensive understanding of the contributory factors leading to struck-by accidents and to explore design solutions that can improve construction work systems.

Sma Ngcamu-Tukulula (CPE), Smart Ergonomics

REFERENCES

1. Cox K (2020). Ergonomic design is the best weapon to reduce risk. Proceedings of the 2020 International Symposium on Human Factors and Ergonomics in Health Care
   
2. Wilson JR (2012). Fundamentals of systems ergonomics. Work, 41: 3861-3868 (DOI: 10.3233/WOR-2012-0093-3861)
3. https://www.fem.co.za/fem-2022-construction-industry-workplace-accident-statistics/
4.  CDC website: https://blogs.cdc.gov/niosh-science-blog/2020/10/01/struck-by-injuries/#:~:text=Wear%20appropriate%20protective%20gear%20(safety,contact%20triggers)%20for%20nail%20guns.
5. The Centre for construction research and training (CPWR, 2018). The construction chart book: The U.S. Construction Industry and Its Workers Sixth Edition.