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

Issue 63: March/April 2016

State of the Art

By John L. Ryan, P.E.

© 2016 M.A.S.E. LLC

State of the art is an important term in product liability cases. State of the art could be defined as to what the standard industry practices were at the time of manufacture for a specific product. Another definition could be what technology was available for the manufacturer to use at the time of manufacture. These are two vastly different definitions. The first is based on what was normal at the time, the second is what was possible at the time of manufacture. There are many safety features that are possible based on available technology, but these safety features may be relatively unknown, may be cost prohibitive, or may not have been adapted for a specific purpose.

State of the art is important because it can establish what could have been done at the time of manufacture to make a product safe, but wasn’t done. Establishing state of the art is necessary in order to be able to make valid arguments on whether a product was unreasonably dangerous. Changes in the state of the art have resulted in huge changes in what is considered unreasonably dangerous.


An example may help clarify the concepts. Many machine guarding and industrial accidents involve unguarded machine hazards such as nip points, shear points, crushing hazards, and entanglement hazards. Industry and OSHA standards are very clear and require these hazards to be guarded. Simple barrier guards can be equipped with limit switches that can stop a machine if a guard panel is opened, to prevent someone from being exposed to the machine hazard. This is referred to as an interlocked guard. Part of a claim against a manufacturer that a product is defective is to show that the problem could have been solved or prevented. In this case, U.S. Patent 1,082,188 provides evidence that safety interlocks were being used in 1913 to stop machine motion upon guard removal.

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In-running nip points can be effectively guarded using old or new technology

Other patents show the progression of this technology. In 1959, U.S. Patent 2,794,528 prevents machine startup if a guard is not in its proper place, and also prevents a guard from being removed or opened if the machine is in operation. Another 1959 patent, U.S. Patent # 2,882,445 describes magnetic coding of interlock switches to prevent tampering. The Accident Prevention Manual published by the National Safety Council has been a safety reference for many decades. The 1951 edition discusses guard interlocking in great detail, and provides multiple examples and photographs of this technology in use. The 1969 edition of this publication also provides additional examples. These references that establish when machine guarding technology was developed, as well as when interlocked guards were standard practice. This doesn’t necessarily establish the earliest date that safety technology was standard practice, but does show that any machine produced after 1951 has no excuse to not be using interlocked guards.

Another example of state of the art would be that if a new automobile today does not have side-impact and roll-over sensors that deploy curtain airbags, one could argue that the vehicle is unreasonably dangerous because this technology is available today. Fifteen years ago this argument would hold much less weight due to the relatively recent advances in automobile safety technology. But the argument is deeper than that – the technology to be able to sense side impacts and roll-overs has been around much, much longer than that technology has been put to use to make automobile occupants safer.


Power transmission hazards typically require simple guarding measures

How is State of the Art Established?

There are different methods of establishing state of the art. Press releases by manufacturers will often discuss safety features. These press releases are dated, providing definitive time of production. Modern press releases can be located using internet searches. Advertising brochures from manufacturers also help establish the state of the art. Locating older advertising brochures is not an easy task, although now some advertising brochures are online, and if they are in .pdf form they are often left online and accessible for many years, and they provide a specific date of printing under the properties of the document. Patents provide a detailed look into available technology at many different time periods. Patents are one medium that are fully accessible today, even for patents a hundred years ago or more. Patents represent progression, and safety technology detailed in patents often take many years to be incorporated into products. Patents are also proprietary, which is another factor to be considered in whether a manufacturer could have made a safer product. Industry standards are another excellent method of establishing state of the art. Industry standards are researched extensively and provide information on what technology was considered to be standard industry practice at different points in time. Obtaining archived standards can be a challenge, but are available for many different types of industry and products. Operator’s manuals may also be a source of establishing state of the art. These are more difficult to obtain, although manufacturers are moving towards online operator’s manuals so that people who buy used equipment can easily find the information they need to safely operate a product. A less used method of establishing state of the art is to buy a product that was produced in the past, that is physically available for inspection, and has important safety features.

So when should manufacturers adopt technology that makes their products safer? When, if ever, are they are required to? When it is possible? These are the questions that a jury will consider. While there are no clear-cut answers, establishing when a safety technology was first invented, when it was made widely available, and when/if it was put to practice in the industry are the pieces of information that are necessary for a jury to make an informed decision.

 How MASE Can Help

We can help to identify state of the art for products involved in product liability claims. We can also determine the cause of an accident, whether it is due to a design defect, manufacturing error, material defect, or human error. Contact us at (855) 627-6273 / info


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