Licensed Professional Engineers



A newsletter dedicated to keeping attorneys informed of the technical side of product liability cases.

Issue 74: Summer 2019

When the Unexpected Happens

By John L. Ryan, P.E.

Some people involved in accidents have awareness that they were in harm’s way, especially if they have bypassed a safety device, but for most people involved in accidents there is no awareness of a hazardous condition or a potential user error. This prevents people from taking action to protect themselves, and leaves accident victims wanting answers. This issue of Forensic Clues will take a look at subtle factors involved in accidents, especially machine guarding accidents.

Why are So Many Accidents Unexpected?

There are different factors leading to the unexpected nature of accidents, including lack of awareness of all of the hazards of a machine or product, under-estimating hazards, being over-confident of one’s ability to avoid a hazard, being unaware that safety systems had been bypassed, assuming that the machine was safe to operate, being in a work culture of acceptance of workplace hazards and putting the burden of safety on workers instead of ensuring a safe workplace, thoughts of invincibility, distractions, as well as failures in machines, guarding, or products that could not be foreseen.

 Lack of Awareness of Hazards

Some accidents occur due to someone being unaware of the presence of hazards, under-estimating the severity of a hazard, the hazardous state occurs suddenly, or at times when machines are not locked-out and tagged-out when maintenance is being performed. When machines are made to comply with industry standards, it should be impossible to come into contact with machine hazards. In maintenance operations, workers are at times required to access parts of machines that are normally not necessary to be accessed by operators, and can present greater hazard due to these areas being normally guarded, or inaccessible by operators due to other components that block the area. In these situations, lock-out and tag-out are required by law and also prevent inadvertent energization of machinery. Maintenance and repair procedures can also position workers in a place where they can be exposed to a different hazardous machine, or a part of the machine unrelated to their work area that is still energized and in close proximity to the worker. Any machine accident should be taken seriously, and a competent expert hired to determine the cause and any standard violations in order to prevent future accidents. Too often accidents are written off as a freak accident, or due to carelessness of a worker which results in the root cause of the accident not being identified or corrected.

Bypassing of Safety Devices

Safety devices are all-too-often bypassed by workers in order to speed up operations or make them easier. The best safety systems do not slow down production, and are also difficult or impossible to tamper with or bypass. Many guards have simple limit switches to determine if they are in the open position which will cause the machine to shut down or prevent it from starting up. These are easily bypassed by permanently taping down the switch. There are many limit switch options available that are more difficult to tamper with, including switches contained internally in hinges that are not readily overridden. Bypassing of safety devices is often seen as a death sentence to a product liability case, but this is not always the case if there was a more effective as well as user-friendly way to mitigate the hazard that would not slow production or be inconvenient, and would therefore be less intrusive and less likely to be overridden.

Unguarded and Inadequately Guarded Machinery

Many accidents occur due a machine or product not having hazards associated with its use and hazardous components properly guarded. People often assume that a machine is safe due to blind trust as well as the machine having a history of no accidents, or no specific training, warnings, or instruction regarding potential hazards. Inadequately guarded machine hazards violate OSHA and usually industry standards that may be “voluntary” but do establish accepted practice and minimum state-of-the-art. Machines that are not adequately guarded are not always obvious, especially to workers untrained in identifying hazards and what appropriate guarding should look like. There are often brand-new, million-dollar machines that are completely unsafe but have the appearance of being new which can lead people to have a false sense of security. Some custom machinery manufacturers put the burden of guarding on the end user, who do not have the same knowledge of the hazards of the machine, and may not have the ability to guard the machine – often the hazards remain unguarded and ultimately the manufacturer is held responsible although the employer is required by law (OSHA) to provide a safe work place which includes ensuring hazards are adequately guarded. These are some reasons why the manufacturer is in the best position to identify and mitigate hazards.

Psychological factors

Psychological factors such as fatigue, distractedness, over-confidence, a sense of invincibility, being emotionally distressed about something, becoming desensitized to the hazard of a machine, and intoxication are issues very relevant to machine hazards and machine guarding. While a fully alert machine operator who never has a moment’s distraction or lapse may be able to avoid hazards for some time, these factors which are often outside of people’s awareness or control can result in an accident with the most experienced of machine operators. People not trained in accident reconstruction and victims often have their own opinions regarding accident causation that puts all blame on the product even if they contributed to the situation. Expectations can also cause accidents if a machine has hazardous components that a worker is used to dealing with on a different machine or product, where they routinely do something safely on the product they are familiar with, and do that same action on a machine with inadequate guarding which puts them at risk for contacting the hazard.


How We Can Help

At MASE, we can determine if a product or machine is defective due to unguarded hazards or inadequate design. We offer full service mechanical engineering expert witness services.

Call us at (855) 627-6273 / email


What We Can Do For You

Provide mechanical engineering expertise for your product liability case

Help you decide on whether to take a case—we’ll give you a free, no obligation case assessment just call us at (855) 627-6273

Perform detailed and thorough engineering analysis of products involved in accidents

Communicate technical information effectively

Design solutions to product hazards that are left unguarded

Please call us to discuss any questions you have about unsafe products. (855) 627-6273

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