Calculation of the number of synergistic hazards and risks on construction sites that limits the efficacy of risk assessment matrices
An interesting theoretical and mathematical paper discussing the potentially “ineffectual … traditional risk assessment and risk matrix approach” for accounting for synergistic hazards (e.g. the interaction of hazards, reflecting the complexity of real-world situations).
Not a summary – so check out the paper:
·???????? “Maharaj (2012) has described synergistic hazards as those involving the interaction of the hazards presented by people, the environment in which the work takes place and the tasks being undertaken”
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·???????? “The number of hazards that can exist on a construction site is large, for example in Maharaj et al (2012) 40 types of hazard have been categorised”, and when combined with the number of workers on site, the “number of synergistic hazards to be assessed can rise exponentially”
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·???????? “A standard risk matrix, used not infrequently by the safety profession … utilises a simple likelihood of an event occurring x severity of outcome”, often with a scale from 1-5 for each component
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·???????? This “gives a 5 x 5 = 25 possible outcomes that are classified” via red, amber and green
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·???????? “However this matrix fails in that it does not take into account the possibility of multiple non-fatal injuries per worker in any given accident”
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·???????? That is, matrices typically consider single, discrete hazard interactions
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·???????? When synergistic hazards are considered in the context of 5 workers exposed to 5 hazards with 3 levels of injury = >14k possible injurious outcomes
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·???????? Further, on a larger site with 40 hazard types and 100 workers = 1.393...x 10^42 subsets or synergistic hazards [*** wow]
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·???????? “This is a truly phenomenal figure of synergistic hazards and all have the potential for the same 4 levels of (non-fatal) injury”
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·???????? When fatalities are factored in, there are potentially: 2.091...x 10^43 subsets of non-fatal injury combinations [!!!!]
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In summing up the “truly phenomenal figure[s] of synergistic hazards”, they argue:
·???????? “The process of risk assessment … cannot realistically achieve what it aims to do because of the truly vast numbers of synergies generated, but nonetheless has succeeded in generating substantial amounts of unnecessary paperwork” (emphasis added)
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·???????? “Hazards exist, often discretely, but in the interaction between the worker when on site, the tasks being conducted and those hazards, new synergistic hazards emerge with increasing degrees of complexity as multiple hazards, workers and activities merge in the developing project”
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·???????? “These synergies mean that the hazard cannot be eliminated, they must be controlled in a manner commensurate with the nature of the hazards and the degree of complexity”
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·???????? “The mathematics herein illustrates how many synergistic hazards there may be on a construction site, but more importantly it illustrates how ineffectual the traditional risk assessment and risk matrix approach is in accounting for, describing and identifying all the controls for all the synergies” (emphasis added)
Ref: McAleenan, P., & McAleenan, C. (2015). Calculation of the number of synergistic hazards and risks on construction sites that limits the efficacy of risk assessment matrices.?Proceedings of CIB W099 Benefitting Workers and Society through Inherently.
#Veteran. Ex Offshore Wind farm Construction Safety, Design, Operation, Maintenance. Behavioural Safety Specialist. Active member of RedRisks Stream Team.
2 个月Disconnect Between Theory and Practice: Desktop Risk Assessments: These are often conducted in a controlled environment, far from the complexities and unpredictabilities of actual construction sites. They tend to rely on standardized templates, risk matrices, and theoretical models, which can oversimplify real-world conditions. Real-World Application: On-site, workers face dynamic and constantly changing hazards that may not have been fully anticipated during a desktop assessment. This disconnect can lead to an underestimation or misrepresentation of the true risks involved. This is not unusual in our cut n paste world in which we now live and work. The paper argues that the risk matrix approach can lead to excessive documentation, which may become an end in itself rather than a means to enhance safety. This can result in a "tick-box" culture where the focus is on completing paperwork rather than genuinely assessing and managing risks on the ground. In some cases, the sheer volume of paperwork can overwhelm workers and management, leading to important safety considerations being overlooked or misunderstood. The overload of paperwork is again not untypical in the fast-reacting contracting world.
Contractor Management and Safety Culture Specialist
3 个月If the study suggests that doing a stack of hazard assessments and making a register, which took hours to make and now minutes to download and copy paste... is ineffectual? Ya. There were and are safe sites that don't use a number matrix. I understand them well... taught them for years, as well as their weak points. 1. The matrix that identifies significant hazards by numbers... the ones that Must be controlled at a certain number is begging for someone to fudge numbers. 2. Workers don't think in numbers.. stop trying to make them think in this arbitrary way. Hazards are things that can hurt you ... don't let them hurt you. 3. Once you have your hazards all beautifully printed out. There isn't anyone who has the time, patience, capacity and interest to read them all. You can do it...2 day inductions. Anyone study information retention decay rates? Many of the workers aren't studious... and the class room setting leaves then numb or nervous or both. IMO the matrix adds little to reducing injury. In my experience, it wasn't the lack of hazard assessment...it was the will to do it anyway... that puts most incidents on the map. Calculate driving to work if you want exponential risk numbers.
Systems Thinker I SVP I Innovator I TechLeader
3 个月Ciarán McAleenan and Philip McAleenan. Great to see your paper here. I remember our pre-2012 ruminations on the subject. Thanks for the post Ben. As a value add, of all 16 fatalities I've investigated, majority were caused by synergistic hazards.
Owner, Total Injury Prevention Specialists
3 个月My biggest worry is this. People talk about identifying hazards and assessing risks. Can you tell me whether the average worker can do either well? If they don't UNDERSTAND the potential hazard component, where are they? Certainly in my area of musculoskeletal risk, people regularly put themselves in regular hazardous positions. Its NOT THEIR FAULT if appropriately uneducated ??
Head of HSSEQ @ P&O Maritime Logistics | Empowering Safety Focused Cultures | Advancing Maritime Decarbonization | Championing Continuous System Improvements
3 个月Honestly, i think they have misunderstood what a risk assessment is or they have little practical experience using one. The matrix is just a tool within the process, they’ve completely missed the value in the discussions and collaboration between the teams when managing risks. I also think they have exaggerated the complexities of hazard combinations and as said above offers no practical alternatives to improve current methods. Perhaps we should all start using a 3x3 matrix ??