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Categories: Webinars, Human Factors

Human Factors in Product Liability Cases


This webinar is designed to discuss how Human Factors can impact on Human Error, discuss human factors models, and the effect of human factors and product liability. It will address what Human Factors is and the study of the interrelationships between humans, the tools they use, and the environment in which they live.  Attendees will learn how these interrelationships effect Product Liability issues such as Design, Engineering, Manufacturing, Maintenance, Instructions and Warnings and Intended and Foreseeable Use and Misuse.


About the Expert

Mr. William Nelson has over 30 years of experience in Ergonomics, Biomechanics, and Human Factors. Mr. Nelson's expertise and areas of specialization include product liability, personal injury, premises liability, and accident reconstruction. He has been directly involved with the commercialization of emerging technologies such as holography, lasers, acoustic reflectometry, and electronics. Of special interest to Mr. Nelson are the unintended consequences from the use of emerging technologies in today's multicultural society. Of particular interest is the emerging research in the areas of Driver Distraction, Sports Injuries, and Medical Errors, and how to help prevent injuries. Mr. Nelson has been a presenter at national and international conferences. He has over 18 years of litigation support experience as an expert witness throughout the US in municipal, state and federal Court as well as experience with the Dauber hearing process.


Carol: Good afternoon, everyone. And welcome to our presentation today. I wanna thank everyone for joining us and for our presentation of Human Factors, Product Liability, and To Error is Human. Our presenter today is Mr. Will Nelson. Mr. Nelson has over 30 years of experience in ergonomics, biomechanics, and human factors. His expertise in areas of specialization includes product liability, personal injury, premises liability, and accident reconstruction. Of particular interest to Mr. Nelson are the emerging researches in the areas of driver distraction, force injuries, and medical errors, and how to help prevent injuries.

Today's webinar is designed to discuss how human factors can impact on human error, discuss human factors models, and the effects of human factors and product liability. It will address what human factors is and study of the interrelationships between humans, the tools they use, and the environment in which they live. We will discuss how these interrelationships affect product liability issues such as design, engineering, manufacturing, maintenance, instructions and warnings, and intended and foreseeable use and misuse.

If you have any questions today, Willy welcomes your questions. And we would ask that you use the chat feature, which is located to the right of your screen. And we will be taking intermittent breaks, excuse me, during the presentation so that he can respond to you. Tomorrow morning, I will send out an email with a link to an archived recording of the webinar and a link to the PowerPoint presentation. So, please look for those in your inboxes.

Also, before leaving the presentation today, I ask that you take the time to fill out the survey that will appear on your screen after today's program. And let me remind you that if you are applying for CLE credit, please complete the survey at the end of the presentation. I will now be turning the program over to our distinguished presenter, Mr. Will Nelson. Will, the program is now yours.

William: Thank you, Carol. Appreciate this opportunity to present today. We have a very timely topic of human factors with the recent plane crash in San Francisco. And also what's been going on over the last year or so with the NFL and football helmets and concussion cases. Obviously, the whole area of human factors, product design, warnings, labeling is a timely topic. And I hope that at the end of today's webinar that all the participants will come away with at least a little better understanding of what human factors is and how it can apply to product liability cases.

This particular webinar on product liability is part of the series that we've done with TASA. Some of the previous ones, just an overview of human factors, we've done one on medical errors, one on distracted driving, and workplace injuries. And I hope that this one is as lightning as some of the others that we've done with TASA.

Today, we will start with just a little bit of time spent on an overview of what is human factors, and we'll go into anthropometry, human error, and then various human factors models. And in the whole second half of the webinar, we'll actually be talking and more specific about the warnings and labels, and then also five or six different examples of products and some of the issues that those products face as they go through the design, engineering, instruction, and warnings aspects of the various products themselves. The examples that we will talk about include a nail gun, trampoline, kitchen knife, table saw, fire extinguisher cabinet, and then helmets.

Let's first start with just what is human factors? In the United States, human factors and the word ergonomics are used synonymous. The ergo means work and nomos means rules or laws. So basically, what we're looking at is how people work, what they do, whether that's in a workplace or whether it's an athlete and what that person is doing, or a consumer and the product they're using, or a professional and the various tools or equipment that they're working with. It has a long history. It actually goes all the way back and as mentioned in the 1700s, Ramazzini, and then in the United States, it really became popular or became in much greater use during World War II and then in the Vietnam war.

Let's first start with what is human error? Human error is just an action or a decision that results in one or more unintended negative outcomes. Very simple definition. Generally, the simpler the task and the less number of people involved the less likelihood of an error to occur. Obviously, this seems reasonable to most people that as you increase the complexity of a task or the number of people, obviously, the assumption would be that that would increase the likelihood of error.

Let's talk briefly about what machines are good at and then we'll talk about what humans are good at. One thing, in particular, is that computer-controlled machines and machines, in general, can do parallel processing, which allows multitasking. This is key since humans really can't do multitasking. Humans can do rapid task switching, but not true multitasking, as it shows every day by drivers who try to drive and text or people walking and texting and running into things. Other things that machines are good at is routine, repetitive, and very precise operations. Obviously, they can exert great force. You see that a lot with construction equipment. Or they can work in hostile environments that you just don't want people to be involved with.

There are many things that humans are good at. We are hearing a lot about the emerging area with the NSA and connecting the dots using artificial intelligence. While robotics and intelligence systems are challenging some of the basic fundamentals of what people are good at, still, at the end of the day, when you get involved with all the data that is gathered and the analysis that is done, it usually is people who make the final determination and decision which is listed here as the ability to exercise judgment where events cannot be completely defined or to perceive the patterns of making generalizations about those patterns. And obviously, as technology advances, it blurs the line of what machines are good at versus what humans are good at. But even, at the end of the day, all the programming that goes into those computers is done by humans. So the computers that control the machines or the products that are made, at the end of the day, it still requires input from humans at some level or at some stage of the process.

So the best solution, as you would expect, usually involves both humans and machines at some level to create the desired result. And so consequently, human factors is the study of the interrelationship between people, the tools they use, or the products that they use, and the environment in which they live and work and use those products. Much of the work in human factors is on improving this system of human tools and environment interface by designing products with less hazards, easier to use, and requiring less maintenance.

A good example of this is I just recently purchased a new car. And as I've done for the last 40 something years, I was filling up my gas and popped the hood and was wanting to check the oil and I literally spent 10 minutes looking for the dipstick to check the oil. And I just knew that there had to be a dipstick there because there had been one for every car that I've ever owned. And lo and behold, found out that there was not a dipstick that it's all done electronically on this vehicle and it just tells you when you need to check the oil.

So looking at that from a interface of a person and the product, the vehicle, and the environment, the driving, one can very quickly see that by eliminating the need for the consumer to have to open the hood of the car, you have engineered out a problem or hazards of exposing the person to one is the toxicity of the oil itself, the possibility of getting cut by or trapped by a moving part, whether it's a fan or a belt, or being burned by the heat of the engine. And it also eliminates the need for a warning since you wouldn't necessarily be looking under the hood for that application of checking the oil. And we'll talk a little bit more about this in some future slides in more details.

Let's talk very briefly here about anthropometry. It's really very simply, it's the measurement of human beings, and it's the various measurements of their height, their girth, their various segments of the body, the legs, the arms, the center of gravity of each of the different segments of the body. And, of course, anytime you're designing products or looking at products or a person and what tools they're using or how they work, anthropometry is a key part of that. Considerations when you look at anthropometry and making decisions on a product and how it's designed or engineered have to take into consideration the person's clothing that they will be wearing at the time of the use of that product, whether those are gloves or shoes, whether that they are wearing a helmet. And then you also have to look at what type of design or engineering criteria do you need to design around.

And for example, do you design for the very minimum, meaning the one percentile of the population, or do you design all the way to the other extreme for the 99 percentile. To give some examples of designing for the minimum, or basically, the smallest or shortest people would be, let's say, push buttons for the floor inside of an elevator. Obviously, if a person in a wheelchair can access those buttons then a person standing up without too much trouble or difficulty can bend over and reach those same buttons. An example of designing for the maximum or the tallest would be opening the height of the doorframe because obviously if a very tall person can get through that door frame, then the short person can also get through that doorframe.

Example of designing for the average would be a checkout counter at a grocery store. Obviously, it's gonna be low for some people, but high for some others, but, in general, it reaches a good broad section of people being able to reach the counter and put the groceries on the belt in order for it to be checked out. And an example of designing for the range of extremes would be an office chair that is designed to go up and down and it has a lot of variety of positions or even the seats in a vehicle that goes forward and back, up and down as lumbar support and the seatback itself goes back and forth. Let me give some examples of how you can design. And that becomes critical in the design and engineering phase of again, who you're designing for. And we'll talk about that in just a little bit too.

So, the six major areas of human factors focus with product liability include the design of the product, engineering of that product, the manufacturing, and maintenance of the product, and then what instructions and warnings go along with that product. We will touch on each of those over the next several slides.

OSHA requires a hazard control hierarchy from the most preferred to the least preferred in dealing with a hazard. Now, while OSHA does not generally get involved with products specifically since they're focused on workplace safety, but the same hierarchy is applicable to products themselves. And the example that I gave earlier about the car without the oil dipstick again is a perfect example of how during the engineering and design process, they engineered out the hazard by taking away the need for the consumer to get under the hood of a car and check the oil. So obviously, engineering out the hazard is the preferred way. However, if because of the design of the product that it's not able to engineer out the hazard, you guard against the hazard, and then at the very least warn about the hazard itself.

Let's talk about the design element. The key here is to know who the intended user is. That drives the entire design and engineering process. Who's the user? What is the intended use of this product? Is it more than one type of a use or is it just a single-use? How will it be used? Who will be using it? That literally is the starting point and the drive when a product is being engineered.

Engineering is where the rubber meets the road. This is where the product specifications are developed which drive the cost and the production. What may appear as a small decision during this phase can lead to disastrous results down the road. Examples of this are everywhere. When you look at the safety recall of products that you see, mainly vehicles, but even consumer products, you see premature product failures in the marketplace all the time. It usually starts in the engineering area where you get involved with looking at the trade-off and the balance between the cost of the item and all the other trade-offs that take place in the what materials you use, how that product is intended to be used, as well as looking at how that product could be misused, or can somebody use it for something that it was not initially intended for. That also should be taken into consideration at this phase. Obviously, looking at any standards, codes, or regulations is important during this phase.

And what's significant in the manufacturing is what quality control processes are being used. Does the company even have a quality control program? What standards are they using? What ISO are they using specific process control, etc., to understand how do they identify whether that product is truly being manufactured to the design and engineering specifications.

Maintenance is usually an afterthought which can lead to the exposure of any hazards, not only to the user of the product, but the person who has to maintain that product. Maintenance manuals can be poorly written, not cover the necessary topics to prevent exposure to unknown hazards. Unknown hazards, meaning unknown to the person who's maintaining it, but hazards that should be known to the manufacturer of the product and should be disclosed and explained, and again, either engineered out, guarded against, or warned about in the appropriate manner.

And needless to say, warnings are an important area in product liability claims. We will go into more detail on this in the second half and talk about the elements that go into a good warning.

Common sense. We hear this quite a bit. Common sense, somebody should have known that this hazard existed or should have known how to use this product. The complexity of the world today as technology advances and as the world becomes smaller and we travel more, common sense never did really exist and it definitely doesn't exist today. Our society's too complex with multiethnic, multicultural, multiracial diversity backgrounds, brings different knowledge, understanding, and expectations to a product. This again gets back to what I'd mentioned at the very start, who is that product designed for and for what purpose? And that drives everything relative to the design of the product, the engineering, the manufacturing process. It starts right there.

It has been estimated that on average, 60% to 80% of accidents involve human error. But those may have been preventable had the system been better, had the folks, the people who designed, engineered, and manufactured the product, had they thought through in more detail of again, how that product is being used and who is going to use that product, how then do you protect that person from the hazards that are associated with that product?

Law of unintended consequences. The key here that I want to point out has to do with new technology. And again, having to do with the rapid emergence of new technology in our society. And it does show any signs that it's going to be letting up as cars get more complex and are getting to the point and Google's testing driverless cars right now, smartphones. When you look at the effect of smartphones and people texting and trying to drive or texting and walking, obviously, the unintended consequences are that of people not understanding the effect that it would have on driving. The complexity of vehicles with all the various technologies that control the engine speed going around corners, control the steering wheel, lights, headlights that can turn around corners. Very few people really understand the complexity of the vehicle that they're driving today. And that makes a real challenge then for engineers and designers to come up with simpler ways to get that information across so that the user of that product can understand the product and can use the product, again, in its intended way.

Another example is football helmets where it reduces skull fracture but has increased the risk of traumatic brain injury concussion as a result of unintended consequences of the helmet protecting the head so well from skull fractures. That some football players were using it actually as part of the tackling itself rather than protection for their head.


And we talked about that. Let's talk a little bit about the types of human error and the causes of those. Two types that you may hear about or have heard about is active errors and latent errors. Active errors occur at the level of the operator and their effects are felt almost immediately where latent errors tend to be removed from the direct control of the operator. They could be hazards that are latent within the product itself. And that product has been used by many, many people, and it's never had a problem and then all of a sudden somebody gets hurt by that product. Just because that error or that hazard that resulted in the error or the incident has not affected people for many, many years does not mean that that hazard doesn't exist and that, that hazard, should have even been engineered out, guarded against, or warned about with that product. And generally, latent errors are a result of poor design, faulty maintenance, or, you know, if you get in looking at the organization itself, as opposed to the product-specifics, you could see bad management decisions or poorly structured organizations for accountability and responsibility in decision-making.

There are also errors of omission and errors of commission. Errors of omission is failing to perform a specific action. Errors of commission are performing the wrong action. In a medical setting, research studies have indicated that up to 90-plus percent of errors are classified as errors of omission compared to errors of commission which helps them to look at where the focus should be from an analysis standpoint to prevent product injuries as a result of hazards in products and their design.

So the basic purpose of the human factors analysis is not to find where people went wrong but is to understand why their assessments and actions made sense at the time. And what you find is when one goes in and talks to people about what happened and what they were doing in their minds at the time, it made sense for the actions that they took relative to either hazards that they didn't know about or hazards that they may have known about but did not appreciate the level of risk or the type of hazard and the effect and consequences of that hazard exposing themselves to that hazard. So the view of human factors analysis is to avoid judging people. It wants to go beyond saying what people should have noticed or could have done instead the view is to try to explain why that incident happened and then try to understand its causes and how it could have been prevented either in the future or could have been prevented early on in the design and engineering phase of that product.


You know, on this slide, when you look at complex systems, human error is not the conclusion of an investigation. It is the starting point. And again, if you followed the airplane crash out in San Francisco every time that the National Transportation Safety Administration folks were interviewed, they would always talk about that they were in data gathering phase. They were gathering information and it was too early. They really want to... They know what happened, now they're trying to understand why it occurred and how it could have been prevented for the future. And that takes time.

We like to separate out accidents from incidents. An accident is an event occurring by chance or from unknown causes. An incident is an occurrence that is a separate unit of experience. And a lot of people will tend to call car collisions an accident, a car accident. Generally, they are not accidents, but they are incidents. There's nothing accidental about it. There is a cause. And whether it's human error or whether it's a product failure by design, somewhere in that system between the person, the use of that product, and the end result an error occurred and an incident occurred. And there is an explanation of why that incident occurred.

Most people have heard of Murphy's law. We believe that this was a corollary. What can go wrong usually goes right, but then we draw the wrong conclusion. So again, it kinda gets back to hazards that people are exposed to all the time. And hundreds of thousands or millions of people can be exposed to that hazard and nothing happens. And people assume then that the hazard is either not existent or that it's such a low risk, or the consequences are so low and then that's when somebody gets hurt. That doesn't mean that the hazard wasn't there. It just means that the right situation did not occur for that hazard to cause an incident. And again, it's gonna be real interesting to see what the airplane crash in San Francisco exactly what the results of the human factors analysis will say on that flight, whether it had to do with pilot error or whether it had to do with the control systems or just what...or a combination of the two that brought that plane in too low.

Okay. With the time, we'll skip a few slides here and get right to the first half questions, and then we'll dive right into warnings and labels and some examples. So I'll be glad to take any questions at this point.

Carol: Okay. well, I do have a couple of questions for you. And the first one is how can an attorney decide if the human factors analysis would be helpful on a case?

William: Oh, that's a very good question. Anytime that there is a product and a personal injury it does well to at least consider whether human factors is a part of the overall investigation. Anytime that there's that interface between the person, the product, and the environment, and the use of it. Just looking at the product itself and not looking at how the human interfaces with that, we think is a missed opportunity for attorneys to get a full understanding and appreciation of the incident and how it occurred, and whether it could have been prevented or not.

Carol: Okay. And then the second question is, has human factors been recognized by the federal courts and also Daubert challenge?

William: Oh yes. Most definitely, yes. Again, the science itself goes way back. It became popularized in the United States after World War II and in the Vietnam War and it's used throughout the United States and the world. Federal courts recognize it, state courts recognize it. Sometimes you'll find some judges who have not heard of the term and it's just a matter of educating them. In some cases, they've heard synonymous terms like under industrial engineering, sometimes human factors will fall or under psychology, human factors will fall. So a lot of times if it's not heard of an alternative term such as ergonomics or one of the other sister disciplines, a judge may have heard of that then understands more of how human factors that can relate to the case.

Carol: Okay. And I have another question. This question is from Gary. Is it possible to quantify the probability of human error in the use of a product?

William: Very good question. Quantify the probability of human error. I think we'd have to look at the specific situation and just see what research may have been done on that product if any. Depending on the device, for example, if you look at a medical device, the FDA requires that human factors analysis be done on that product. It's generally not required for consumer products. Some products that are used in the workplace require it. But as far as quantifying the probability of human error, we'd have to look very specifically at the product itself and the situation and see if some research has been done in that area.

Carol: Okay, thanks, Will. And then this is the last question for this section, and then we'll move on with the rest of the presentation. So the question is, are there degrees and/or certifications that cover human factors specifically?

William: Yes, there are. There's the Board of Certification as well as the Human Factors of the Ergonomics Society and there's the International Association also. I see there's a question here from Robert. Please elaborate further on the proposition that human error is not a cause of an incident. I'm not sure that I stated that. If I did, then it was not meant in that term. Human error can definitely be the cause of a incident. What I was discussing though was from the standpoint that you have to look at the entire system and look at how that person interfaces with the product and all the elements that goes into that, of the product design, who it was intended for, the engineering of that product, the instructions and training, maintenance. All those are aspects that goes into the analysis also. But no, the human error is a key element in that and the use of the human, as I mentioned with the plane crash out in San Francisco.

Carol: Okay. I think, Will, those were the questions for this section so we can continue on with the presentation.

William: Okay.

Carol: Okay, great. Thank you.

William: All right. Let's talk a little bit about warnings. I'm sure we all know employees who should be wrapped up with caution tape. Seems like there's some people that are just prone to injury and there's research that's been done in that area. And discusses a little bit about types of people who are more prone to injury than others, but that's not the purpose of this presentation. I just thought it made a good slide for somebody inside of an elevator to protect them from getting hurt.

All right. So safety communication is used to inform people about hazards so that undesirable consequences are avoided or minimized. There are many different kinds of warnings that could be anything ranging from signs, and placards, labels, inserts, manuals, tags, could even be audio, videotapes, or face-to-face, verbal instruction, but the key elements of a warning include the hazard label. In this case, it's actually a warning as opposed to a hazard, as opposed to a caution or a danger. Identify what the hazard is, identify the consequences of the interaction with the hazard, and how to avoid the hazard. And then on the other side, we have a graphic symbol of the consequences of interacting with the hazard also.

Just on that one warning were many of these elements that are considered as part of the design of an adequate warning label or warning itself, the font, the size of that font, the colors, the shape of the label, legibility, which is whether it's recognizable or not, the readability, whether it's comprehensible or not, the graphic symbol, the layout, the illumination of it, how to deal with curved surfaces. All of these are elements that have to be taken into consideration when designing a visual warning.

I use this as just an example. We're all very familiar, obviously, with the stop sign. And this is just used to illustrate how a very simple change can have a drastic consequence on the outcome. And if you take a stop sign, which is very simple, but yet it has a very clear font, a graphic symbol, the shape, the red, all of those go into your interpretation of what to do when you see one. And a simple change of keeping the shape the same, but changing it to green and putting the words go, as you could imagine, would create havoc at an intersection. And it would be really interesting to see whether people would actually stop or whether they would go or whether they'd stop and then go just by making a little change that it goes to show how a simple change can create vast confusion.

Okay. So there's four main purposes of a warning. Communicate important safety information, hopefully, influence or modify a person's behavior, reduce or prevent health problems, workplace accidents, personal injury, and serve as a reminder to persons who may already know the information about the hazard.

So let's talk about some examples here. These examples are just literally some learning examples. I'm not talking about any specific case or situation. Let's take an example of a nail gun that was designed for a professional. It requires specialized training to operate. You have to have a compressed air tank to be able to connect it and have a certain amount of air pressure to operate it. It takes special type of nails that go into it. And the size of the nail gun ranges anywhere from a small finishing nail, roofing nails, framing nails. And as you can imagine, framing nails would take a lot bigger nail gun and also a lot more air pressure to operate properly.

Let's talk about a roofing situation where the nail gun is used in what is called a bump process, where basically you keep your finger on the trigger, and every time the tip of the nail gun contacts the roofing surface, a nail is fired. Obviously, this makes them easier to operate because you don't have to pull the trigger every time. And if you're working on the roof the specific location of the nail is not near as important as it is in a finishing nail. And so a worker could very quickly get the nail to be very efficient and very productive in using the nail gun and contacting the surface.

So let's discuss a little bit about what happens though when you take that type of a nail gun and put that in the hands of a consumer. We're all familiar over the last 20 years with the increase in the number of blows in Home Depots around the country. And nail guns are marketed to not only professionals but also to consumers. There's nothing to prevent anybody from basically buying a nail gun. You can take that same nail gun, you put it in the hands of a consumer who says, "Yeah, I think I could, you know, use this." Who really doesn't have much knowledge on the use of the product or understanding of how it operates. And they're in the process of using it. They've put a nail in. They've got their finger on the trigger and they turn around when they get startled by either their son or somebody comes up next to them, they turn around and accidentally the nail gun fires and puts a nail into somebody.

Well, this is a situation where, as I mentioned at the very start where you have to look at the nail gun and who it was intended for. At the very start of it is really intended for a professional, somebody who's trained, somebody who appreciates its danger and its hazard. And in the hands of a consumer, this product with this type of a feature, a bump capability is probably not the best type of feature they have. So then the question becomes, how do you change that nail gun to turn into a consumer, or can you engineer it out? Can you guard against it or do you just strictly warn about it?

And in this situation, it would be very easy to engineer that out. Take that feature out and make that as an optional feature or one that you would have to change some mechanism within the nail gun in order for that activity to take place. Or you come out with a consumer model and also a professional model that way that you can distinguish between the type of product and where it is sold for professionals versus the product that is sold to consumers. And you can then change the way that the instruction manual is designed and written and the type of warning that you warn about, again, based off the intended user.

So this is a situation where again, knowing exactly who that product is designed for is critical because that drives the entire process of how it's engineered, what features it has, and what channels of distribution it's going to be sold in, and who it would ultimately be sold to.

Now, this is a little different example of a table saw because the inherent nature of the table saw is to cut. So obviously, if you eliminate the ability of the saw blade to cut, you've eliminated the functionality of the product itself, which is obviously not possible if you want to cut wood. However, this is an example of a product that well, it can not necessarily be engineered out. It can be guarded against and also warned about the hazard. And you've seen the evolution over the last 20 some years of the types of guards. A table saw when it first had guards put on, you couldn't do certain types of wood and you'd have to take the guard off in order to cut that type of wood.

Now, the types of guards that are installed are much more flexible and provide much more protection. There's even some patented technology out there that's been demonstrated that if you took a hot dog and actually put the hot dog up to the saw blade, it would immediately shut down the saw blade and you might get cut a little bit, but it wouldn't cut your finger off. But, again, it kind of shows the evolution of no guard, to early guards, to today's guards being more sophisticated to possible technology in the future. And again, in this situation, how that guard is designed, how it is installed, and warning about the hazard, all becomes very critical into the design and functionality of this product.

And this product, which is a cabinet for a fire extinguisher, again, a situation where there's different types of glass or plastic that can be inserted into this cabinet. And I show on the right there, a one with a plastic molded lens cover. The one on the left has just plate glass. This is a situation where there is a school installation. There was no code that specifically required any particular type of a lens or even if there had to be a lens. A person puts their arm through it. And there was nothing in the school code. There's nothing in the building code to indicate that. There's nothing from the manufacturer that indicated a specific type of glass. So the question becomes, again, back to what was its intended use? Does it make sense to put plate glass in a cabinet that is going to be in a school environment where you have kids who maybe had pushed or shoved or fall into it? Does it make sense regardless of what the codes and regulations and standards would be? Would this application for this product did not have either plastic, or tempered glass, or a much smaller opening to be able to see that, yes, there's a fire extinguisher, but does it needed to be glass all the way?

So this is the appropriate use of a product for a specific application. And again, would not make sense to warn about it with a label because it still would be plate glass. How do you guard against it? Well, you know, I guess you could cover the glass up neatly and only have a very little bit exposed. But the real answer in this situation, again, is to engineer out the problem by going to either a plastic or minimizing the size of the opening so that you can still see the fire extinguisher, but you basically protected it from somebody getting injured.

All right, this is one that again there's no warning and it's not needed. This is considered open and obvious. The knife has to cut. It's designed to cut. Again, people are familiar with knives and what their purpose is. So it does not make sense you cannot engineer out the hazard. You can guard against it as far as where you store your knives, but you can't really... It doesn't make sense that you'd have to warn about the sharp edge of a knife in this situation.

All right. This is an example. Is it possible to make a trampoline really acceptable from a risk standpoint? Again, obviously, the manufacturer thinks that it is. They've come out with nets that are around it and warning signs that go on it. But the question is, is that when you look at the injuries from the consumer product safety commission, most of the injuries that occur are still on the trampoline and not falling off of the trampoline. So if you have a net, it may prevent somebody from falling off the trampoline, but that still doesn't eliminate the injuries associated with jumping on the trampoline itself and landing on your neck and resulting in a neck injury.

So the question becomes, is this a product that should be on the market? Is there a way to make it safer? Some of the physician groups have come out and actually said that the product should not even be on the market itself. Is it acceptable to warn about it? When the primary use is by children as opposed to adults, is it reasonable to expect that an adult would provide supervision to a child while they're playing on the trampoline? Is it expected that only one person at a time would be using the trampoline when the reality is that it seems like more than one child at a time gets up there because that makes it more fun? So it gets all involved in the aspects of the product, the design of the product, again, who it's intended for, and the amount of risk associated with the use of this product by the intended user. And is it possible then to actually engineer it out, guard against it, or warn about it appropriately?

Then the last example here is just various types of helmets. Some of the issues from a human factor standpoint gets involved with compliance, meaning the use of the helmet. There are some studies that have indicated that when people are protected buy various safety devices. Some research involving bicyclists and also with cars, and when you have seatbelts, shoulder harnesses, airbags, side airbags, roof airbags, in crash zones, all the various safety features that sometimes drivers actually take more risks because they think that they have so many safety features involved that they can take those risks and if an incident happens, the likelihood of them getting hurt is very low.

And the same could be said about whether with bicycle helmets and football helmets. Looking again, as I mentioned earlier about football helmets and they have done a great job of protecting the skull, which is what their intended initial design was for, but how does that then relate to some of the issues today with questions about concussion and TBI. Football helmets are designed for multiple impacts where a bicycle helmet is designed for a single impact. How do you know if your bicycle helmet has been damaged and needs to be replaced? How do you ensure that it's worn properly and fit properly? And then do you legislate the use of the helmets or do you just recommend their use?

It's a lot of issues in the helmets that our society has wrestled with over the years and varies by the state law in some cities in looking at helmets and how do you engineer those helmets? How do you warn about the use of the helmets and what they're intended for, but not intended for? And what do you do about those hazards that the helmet is not intended to protect, but maybe the end-user thinks that they are able to protect from? All human factors issues that designers and engineers wrestle with all the time and looking at, again, the intended purpose of the product and the intended user of that product, whether it's a child or whether it's an adult or a professional, which makes a difference in the use of that product.

Well, my time is just about up here. Wanted to see if there's any more questions, last few questions here, before we wrap up.

Carol: I do have some additional questions for you, Will. And I do encourage all of our attendees to submit their questions through the chat feature. This is an opportunity for Will to be able to answer any of your specific questions. The first question I have is it does seem that human factors analysis generally concludes that the person is not at fault. Does a human factors analysis ever conclude that the product was properly designed, the instructions were clear, and the proper warnings were included?

William: Oh yes, most definitely. Yeah, there has to be a kind of a perception that whenever human factors professionals analyze a situation that it's never the person's fault and that's just simply not the case. And the humans play a very important role in the overall system. And the training becomes important again, the intended use of that product and how that product is used and the person has to be able to use that product and not be, you know, using alcohol or being on drugs or a host of other things of being distracted. They can affect the user and how they use the product. And they obviously have accountability and responsibility for the use of that product in the appropriate setting. So, you see that regularly where the person is also contributory to the end results of the incident happening.

Carol: Okay. And you use the examples of the nail gun and also the trampolines. Are there specific standards for these types of products and whether they would be intended for, say, personal use or consumer use versus commercial use? Where would one go to find those standards if they had a question about a product design, or if, in fact, it met the standard?

William: Well, when it comes to like a nail gun, it would depend on the specific aspects of that nail gun, or what types of standards or regulations that we would be talking about. I'd need to know more specifics about that. When it comes to the trampoline, I think we'll just have the second, Carol, with the trampoline?

Carol: Yeah. So that was the second example. And that would be, for example, a consumer use of a trampoline, say, like in someone's backyard.

Wiliam: Yeah. I'm not aware of any particular standards there might be for trampolines. Some industry standards. But a lot of times when you look at industry standards, it's made up of the manufacturers of the product itself. And a lot of times to be real honest those standards are not very stringent and they do not generally stretch the designers, engineers, and manufacturers to really engineer our products as much as they look at strictly warning about the product itself. So I'm not saying that that's the case with trampoline. We'd have to look into... I'm not aware though from the work that we've done over the years of specific safety standards of trampoline that governmental bodies have gotten into.

Carol: Okay. And I do have a question and this is actually in the area of transportation. Is human factors ever used in deciding where crosswalk or lights should be placed on highways or streets or is it more just an engineering decision?

William: No, human factors play the key role into that. Now, there are general guidelines that codes have adopted based off of, you know, the streets and setups for sidewalks and the timing of those lights and how much time you have to walk across the street, things like that. But it's all based off of human factors study. But there are many situations out there where you have to look at the uniqueness of the situation and the application of human factors that the codes may not specifically address. And we'd have to look at that individually on how that setup should be done to incorporate proper human factors analysis.

Carol: Okay. And then this is an additional question. Are there regulations that require human factors analysis as part of product development?

Wiliam: Yes. Depending on the industry again, as I mentioned earlier that when you look at medical devices it's required that you have some human factors analysis on the product itself. A lot of industries have general guidelines of looking at, from the human factors standpoint, but, in most cases, it's really up to the engineering group to reach out and look at the product from a human factors standpoint as opposed to any specific standards or regulation. Again, I'd mentioned earlier about the hierarchy of engineering it out, guard against, warn about. That's a pretty standard hierarchy to use. OSHA uses that and good product designers and engineers will also look at that hierarchy and identify the hazards and try to follow that hierarchy. It's a good standard practice.

Carol: Okay. And we have another question from Robin. And Robin asks regarding the placement of fire extinguishers in businesses, are there standards as to the placement of the fire extinguishers and safety harnesses of cabinets to be used?

William: There are standards required for factories really to general placement of fire extinguishers and the signing so that people can find those fire extinguishers. The codes tend to be very varied as far as cabinet and the type of enclosure, and if any protection is required of that fire extinguisher. So it would depend on the specific situation. But generally, the codes are more as far as the general location, that the area has to be cleared for access to get to it, as opposed to the particular cabinet that it goes into. But I'd have to know more about it, whether it's an office environment, whether it's a factory, whether it's a warehouse, and where that specific one would be, and what codes would be applicable. Fire codes tend to be very city-oriented.

Carol: Okay. And I have an additional question. What information do you look for when first investigating a product liability case?

William: Say that again, Carol?

Carol: Sure. What information do you look for when first investigating a product liability case?

William: Well, it depends on the phase of the lawsuit of whether it's pre-litigation or whether it's in the middle of discovery. If it's pre-litigation sometimes we'll get called in to assist an attorney on whether to even take on a case or not. We would basically look at just either whether it's a statement from the injured party, and analyze the product itself, look at the manual that's associated with the product or instructions, and try to understand more of a cursory or more of a broad-brush approach of what the issues are. Generally, though, we get involved in the middle of discovering you have, you know, depositions, medical records, interrogatories, photographs, do a site inspection, we'll get the product in and analyze it.

And then look at what codes, regulations, standards that apply to that product. And then look and understand exactly how that product was used in that situation. And then go through and we didn't talk about it today, there was a slide I skipped over, go through either like a root cause analysis where you really start to understand exactly what occurred and how it occurred. Some cases it's a situation where it's a snowball effect, whether it was one small error that took place and that led to another decision that was an error. Led to a bigger decision that was a bigger error and then ultimately led to the incident itself.

So we look at a variety of the documents and photographs and the product itself, though, it was very important to have so that we can see if the product itself has been maintained properly, or is defective in some form or fashion, as well as, again, the testimony of the user or witnesses of what happened and so that we can look at that system of the person, the product, and the environment that it was used and determine the causes of the incident.

Carol: Okay. Thank you very much, Will. That seems to be the end of our questions for today. And I wanna thank you very much for your time and your effort in this presentation. As I said earlier, we will be sending a link with the presentation to all of the attendees. And if you want to reach or get in touch with Will, you can certainly give us a call here at 1-800-523-2319. For those of you who are looking for CLE certification, please again, be sure to complete the survey at the end of the presentation. This webinar is eligible for CLE credit in Illinois, New Jersey, Missouri, and Texas, and it is also pending approval in Minnesota. Again, I thank you very much for attending. And in our closing, I'd like to make all of you aware that we do also now offer research reports on expert witnesses and also e-discovery and document management solutions for those who might have any interests. Again, thank you again for attending, and have a great day.

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