What Is A ‘Human Factors’ Expert Anyway?

Have you ever wondered exactly what ‘human factors’ referred to, but were to afraid to ask? Over the last decade, human factors experts have played an increasingly significant role in the handling of claims and litigation. Presumably, most claims stem from human involvement at some point, so a better question to ask might be which types of claim investigations require human factors expertise.

Human factors refers to the study of the interaction between people and their environment, in particular with technology, products and tools. Human factors experts study the limitations of the human body in three general areas: physical limitations, sensory limitations and cognitive limitations.

Physical human limitations include strength limits for various tasks, speeds of ambulation, range of motion and anthropometry (the study of bodily dimensions of population groups). The study of traditional ergonomics typically falls within this category.

Sensory human limitations include perception, nighttime vision, visual masking, sound masking, tactile sensation and tolerance to acceleration and deceleration.

Cognitive human limitations include reaction time, complex decision making, mental fatigue, control display design, signage design/complexity, warnings/instruction design and the ability to estimate speed, distance or time.

In the insurance and legal industries, “human error” is typically identified as a contributing factor to a claim. However, human factors goes beyond just the assessment of human error. For example, human factors knowledge can be used to help assess the accuracy of witness estimations, the appropriateness of a particular safety factor, or the time required for a particular series of decisions.

Consider the following three actual case studies where the insurer or plaintiff benefited from the use of human factors expertise.

Case 1: A garage repairman working on a crank at the top of a ladder is seriously injured when his ladder suddenly slides out. Knowledge of the maximum pull/push force that a male can typically exert in that position allowed for a detailed analysis of the potential for ladder slippage at various ladder angles.

Case 2: A male driver, traveling at night on a well-lit road, struck a pedestrian who ran onto the road and was seen well in advance by a driver traveling in the opposite direction. A precise nighttime visibility study revealed that the background lighting behind the pedestrian was drastically different from the two driver perspectives. As a result, the view of the pedestrian was completely masked during the time of interest from the insured’s direction of travel.

Case 3: A man operating a ‘jet-ski-type’ recreational watercraft was thrown forward off of the vessel and injured in mild-to-moderate waves, despite years of experience on previous models of recreational watercrafts. A human factors assessment of the product revealed that the stability control system for that model of watercraft did not provide users with feedback regarding the current setting of the control system. As a result, an incorrect setting was used, leading to an unexpected loss-of-control.

Case 4: A female driver, driving home during the day, encountered a sharp curve while travelling at high speed and lost control, resulting in fatal injuries to the occupants of the vehicle. Opposing counsel produced a road assessment report, demonstrating that the curve was too sharp and claiming that the warning signage was insufficient. After assessing the signage and finding it to be appropriate for that curve, a human factors expert then noted the driver was thoroughly familiar with the road in its current condition, having driven it regularly for years. Using human factors sources, it was demonstrated that the driver’s expectation of the curve made the issue of signage irrelevant to the case.

In summary, human factors expertise adds a valuable layer of knowledge to litigation and multi-disciplinary claim investigations that may otherwise go unnoticed. The use of a human factors expert to draw upon reliable studies and data can be the difference between a successful litigation process and a ‘Daubert junk science’ ruling.

Jason Young, P. Eng., is a senior investigator and head of the personal injury unit at Giffin Koerth Forensic Engineering and Science, specializing in the human factors of motor vehicle collisions, personal injuries, and product failures.