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Product Liability
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Every manufacturer is liable for the safety and the integrity of his product whether it is used by a human, such as a hand tool, or part of a system that interacts with humans. At the same time, an end user of a product expects that it will function according to its intend but also will be safe to be used. To insure the above thousands of standard were developed for many customer products and industrial equipment. Organizations like American Society of Mechanical Engineers (ASME), American National Standards Institute (ANSI), American Society of Testing and Materials (ASTM) and many others are responsible for the development, review and update of these standards.
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Major Causes
Furniture failure
Chairs, tables and other furniture item do fail due to poor construction or impropriate materials. As an example, US Consumer Product Safety Committee (CPSC) published on March 2017 a report entitled ”In depth Analysis of Nonfatal Injuries from TVs Falling off Furniture”. It was “estimates that annually there are 11,800 television-related (or TV + furniture) emergency department (ED)-treated injuries involving TVs falling. In addition, from 2000 to 2015, CPSC staff has reports of 315 fatalities associated with falling TVs and TV + furniture falling. The majority of the injuries and fatalities with TVs and furniture falling involved children.” Interpolating these results, one can understand that there are by far more accidents involving other items of furniture.
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Kitchen Appliances Accidents
Two major injuries are caused by kitchen appliances: Burns a severe cuts. Appliances such as coffeemakers, pressure cookers, toasters, microwaves and oven operate in high temperature that might cause burns due to design defects or failure. Other devices such as food choppers, mixers or blenders are using sharp edges at high speed which might cause severed fingers. When these products cause injuries, the manufacturer or seller may be held liable
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Lawn mower
Each year, more than more than 75,000 Americans are injured in lawn mowing accidents, and 10,000 of them are children and 75 are killed. (Out of these 18,000 related to riding lawn mower). Blade failure due to impact with hard item, fatigue or any other reason, become a projectile with a speed of 150mph to 250mph. Impact with human body will cause major injury or even death.
Automatic Doors and Gates
There are two basic kind of automatic doors: Powered or non-powered. The first kind include doors which are powered by electrical motors such as in garage door or an entrance to a shop. The other kind have a mechanical/hydraulic closer such as in emergency exits. In both cases, when a door closes on a person it might cause severe injuries.
According to the CPSC (United States Consumer Product Safety Commission), 32 fatalities involving automated gates occurred in a 16-year period, 20 of which involved children – with a massive 25,000 serious injuries estimated in a similar time frame. There are many kind of gates: Sliding, Swinging, Vertical and other. These gates, when coming in rough contact with a person, might cause a very serious injury and property damage.
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Toys and Playground
According to CDC “Each year in the United States, emergency departments (EDs) treat more than 200,000 children ages 14 and younger for playground-related injuries. More than 20,000 of these children are treated for a traumatic brain injury (TBI), including concussion.2 Overall, more research is needed to better understand what specific activities are putting kids at risk of injury and what changes in playground equipment and surfaces might help prevent injuries.”
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Services FEI provides
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Inspect and document the accident
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Determine the cause of the failure
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Check the compliance with standards and codes
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Determine magnitude of forces and torques that caused the injury
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Analyze parts or structure failure using Finite Element Method
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FEI case examples
​Gate closes on a biker
A bike rider approaches the entrance to her community and the noticed that the gate is open. She proceeds with caution moving to the left of the lane just in case the gate will close. As she passes through the gate closes and hits the bike handrails. As a result, the biker lost its balance fell and broke her elbow. Our investigation revealed that the security guard can open and close the gate manually. However, there is a delay of 17 seconds between the guard’s closing “signal” time and the time the gate closes. This delay was unknown and could not predicted by the biker. Also, there was on sign or indication that the gate is about to close. Eventually this delay was the reason for the accident.
Failure of plastic lawn chair
A person seated in a plastic lawn chair was leaning backward causing the front two feet to loose contact with ground. At this instant, the chair is been supported only by its rear legs that immediately broke. Our investigation found: 1) The stress on the rear legs were higher than the ones the material can support; 2) The strength properties of the material were substantially reduce due to the element that the chair was exposed to for a long time (in particular UV radiation). The behavior of the person in this case is quite predictable and therefore the manufacturer had to design a sturdy rear legs. As a matter of fact, a couple of years later, in response for quite a few similar accidents, the manufacture placed a warning label in the front of the chair advising the used not to lean backward and lift the front legs. The question is: How many of us will read instructions label before using a chair?
Kid’s fingers were caught between a door and the door’s frame
A kid, vacationing with his parents, tried to go down to the lobby using the emergency stairwell. As he walked through the door it slammed shut and severed his fingers against the jamb. Our investigation found that the closer was in good condition but was not adjusted to the conditions that frequently occur in this location. In this case there is an open window in the end of this floor’s hole. As high wind blow outside, particularly parallel to the window, it generates low pressure in hole relative to the one in the stairwell. As a result a large force is exerted on the door’s stairwell side which cause it to slam in spite of the closer resistance. Since this “slamming” behavior was experienced in before, the closer should have been adjusted differently and this accident would have never happened.
A lawn mower sends a projectile
A ride-on commercial lawn mower was used in residential area. As the mower passes under wooded area its blade hit a small piece of a broken branch. As a result the wood piece acquired the tangential velocity of the rotating blade and was ejected. The flying piece hit the eye of a person who was walking by. Our investigation showed that the guard, which supposes to block any ricochet, was damaged and stuck in the open position. Also, we could show that the velocity acquired by this piece was high not only to reach the by stander but also to cause the injury.