Cumulative Exposure

Cumulative exposure is exposure to a hazard over an extended period. Injury to the individual may not manifest itself until several years after the first exposure.     

Cumulative exposure is not immediately apparent, in contrast to most accidents and natural disasters. For example, when a home floods, the damage can be seen right away and insurance claims filed based on the evidence gathered at the scene. The same is true of car accidents, where vehicle damage and personal injuries are immediately evident.

Cumulative exposure is more difficult to evaluate and may spread over multiple insurance policies, further complicating claims and legal cases. This creates a protracted liability potential depending on the type of policy the insurer has underwritten. For example, Workers' Compensation policies are more likely to have a high liability potential for cumulative exposure than other types of policies.

Examples of cumulative exposure include repetitive motion tasks, such as those experienced by airport baggage handlers and the increasing number of workers using keyboards to perform their jobs. Carpal Tunnel Syndrome cases have risen dramatically in recent years and carry high social and economic costs, especially when surgical treatment is needed and interferes with one’s ability to work. Many workers and analysts attribute the increased usage of computers in the workplace as a primary reason for rising incidents of Carpal Tunnel Syndrome, when in fact many studies have shown this not to be the case. It is also known that similar symptoms existed long before the advent of computers for workers performing repetitive motion tasks.

The most difficult cumulative exposure lawsuits involve exposure to asbestos occurring over a long period of time, under a variety of circumstances.  An example from 2018 was a case that made it to the Ohio Supreme Court. The plaintiff alleged that the decedent’s father was exposed to the asbestos-laden clothes of her father, who was employed as an electrician, with additional exposure taking place over many years of replacing the brakes on the family cars, brakes made by Honeywell.

An expert testified at trial that it was the cumulative exposure that caused the decedent’s mesothelioma and subsequent death. The jury ruled in favor of the plaintiff and found Honeywell partially liable for the injuries but not completely.

The defendant appealed to the Supreme Court of Ohio on the issue of “whether the substantial factor requirement may be met through a cumulative exposure theory.” The court ruled that it may not because the plaintiff’s theory was flawed given their star witness only included certain exposures and not all of them.