PRISM - American Society for Engineering Education - Logo DECEMBER 2005 - VOLUME 15, NUMBER 4
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A LESSON IN SAFETY - It took a tragedy to focus the engineering curriculum on safety in product design. - By Nancy Cowles and Zachary Hill
By Nancy Cowles and Zachary Hill


Linda Ginzel and Boaz Keysar, professors at the University of Chicago, dropped their 16-month-old son, Danny, off at childcare on the morning of May 12, 1998. Ginzel returned that afternoon and was told that her son had been hospitalized. She arrived at the hospital to find that Danny had been pronounced dead on arrival. That morning, Danny had been placed in a Playskool Travel-Lite crib for a nap. The Travel-Lite, one of the first portable cribs in America, was designed to collapse onto itself when not occupied, so as to facilitate easy storage. The crib collapsed that morning with Danny in it, the top rails creating a “V” shape that pinned his neck. Danny was unable to cry out for help, as the crib suffocated him.

Perhaps the only thing about this story more disturbing than the image of a baby being strangled to death by his crib are the details that were later revealed. Ginzel and Keysar soon discovered that a few years earlier, an 11-month-old in California was strangled when his Travel-Lite collapsed around his neck. Two more children were killed in a similar fashion over the next two years, prompting the Consumer Product Safety Commission (CPSC) to request that the crib be recalled. In February 1993, Kolcraft, the Travel-Lite’s manufacturer, agreed. Posters explaining the recall were sent to pediatricians across the country, and the CPSC issued a joint press release with Kolcraft.

It was known that there was a fatal flaw with the cribs (the mechanism that locked the crib in the open position did not always work properly), and it was also known that thousands were potentially in use. The problem, however, was that too few people knew about the flaw. Kolcraft’s attempts to disseminate the news were an abysmal failure. Neither Ginzel nor Keysar had any idea of a potential problem when they dropped Danny off that morning. More tellingly, however, the news had never reached the operator of the childcare facility. None of the parties involved were aware of the crib’s fatal flaws, but all would become grief-stricken witnesses to its latest victim. Just months after Danny’s death, the Travel-Lite killed again, collapsing on and killing a 10-month-old baby in New Jersey.

Ginzel and Keysar eventually sued Kolcraft and Hasbro, who had licensed the use of its Playskool brand, for negligence and settled out of court for $3 million. The couple founded Kids in Danger (KID), a nonprofit organization whose mission it is to ensure that parents never have to suffer the agony of losing their child to something as preventable as a recalled crib.

What went wrong with this crib? Unfortunately, the story of the Travel-Lite crib is indicative of the child-product manufacturing system. Through court documents, it was later revealed that the crib had been designed by a draftsman with a high school education. Addressing the problem of nonexistent standards is difficult, and KID’s mission is to push for stringent and mandatory testing of all children’s products before they are sold. KID also believes, however, that if any of the engineers who worked on the Travel-Lite crib had been more aware of safety issues, Danny and the 15 other babies who died in cribs of similar design might still be alive. In 2003, KID began developing, with funding provided by Underwriters Laboratories Inc., the TEST (Teach Early Safety Testing) program to tackle these concerns.

Student Solutions

Working prototype of the baby crib designed by students at the University of MichiganTEST began with a preliminary review of the syllabi of several major undergraduate engineering programs in 2003. No courses were found that emphasized safety, or even used the word safety in the syllabus. The staff at KID quickly developed a lesson plan and program, and the results were telling. The problem of the collapsible portable crib was solved by a group of University of Michigan seniors who had been challenged to design a safe portable crib. The student group designed a portable crib that folds upward, eliminating the possibility that it could collapse onto a baby. Even more impressive than the result is how this product was developed. The students were merely asked to design a portable crib with safety in mind. The result seems to suggest that if engineers were presented with information on safety concerns, they would be able to easily incorporate it into their product designs.

Inspired by the success of the Michigan group, TEST projects began at Northwestern University last spring. After receiving a lesson in safety matters specifically designed by KID, five teams of freshman engineering students were challenged to find solutions to long-standing child safety problems. The groups received detailed descriptions of the problems with no constraints on what type of solution was expected, except that the redesigned product must be safe, effective and feasible (i.e., cheap enough that a manufacturer would produce it).

Final design of the "shopping basket" baby carrierOne group was assigned to the “baby carrier problem.” Many baby carriers are similar to the Travel-Lite crib in that the carrier appears to be properly locked when it is not. The result can be the carrier’s handle collapsing with the baby inside, possibly causing the baby to fall to the ground. Flawed carriers have killed at least 20 children.

The students began this challenge by examining a faulty baby carrier and identifying scenarios in which the problem may occur. They ended up completely redesigning the handle, settling on a “shopping basket” design, in which there are two handles instead of one. The handles emerge from the carrier and come together above it, where they are locked in place. Unlike other models, this carrier has its lock in an obvious place at the top of the handles. Furthermore, the carrier has been designed so that it works only when the handles are locked correctly. Try to pick up the carrier with only one handle, or with the handles not locked properly, and it will be clear that it’s not operating correctly. The carrier was built using a low-cost, abundant plastic. Coupled with a simplistic design, the carrier would be potentially very inexpensive to manufacture.

Working prototype of the baby crib designed by students at the University of MichiganThree teams were assigned to look at baby monitors. Monitors are popular among parents of newborns, as they allow the parents to observe the baby from their own bedroom. But some have been recalled for overheating to dangerous temperatures. The goal for the teams was to create a monitor that shuts off if it begins to overheat and warns parents that it is no longer functioning. The three teams took different approaches to the problem: One created a new style of monitor, incorporating a fan and automatic shut-off; one added thermal cut-offs, causing the monitor to shut off and become permanently inoperable; and the third devised a fan and shut-off that could be incorporated into current baby monitor models.

The final group was challenged to improve a common problem in cribs: hardware failure. Cribs can operate perfectly for several months or years, only to collapse suddenly due to a screw that has become worn or loose. This group was asked to develop a way to inform parents when a crib’s hardware becomes faulty. The group’s solution involved two innovations: a “drop-side safety system” and a warning system. The drop-side safety system is a small plastic mechanism that can be added to the foot of any crib. When attached to the crib, it securely locks the drop-side rail in place. The safety device can be easily operated by parents or caregivers but is out of the reach of the crib’s occupant. The second part of the group’s solution involves a simple system that warns parents about loose screws. It consists of a rectangular piece of plastic that stands upright when the screw is tight. As the screw loosens, however, the plastic begins to fall, revealing a brightly colored warning sticker. A caregiver could check for loose screws by walking the perimeter of a crib and looking for brightly colored stickers.
The students are enthusiastic about what they learned. “It has taught me how to go about designing and solving real-life situations,” says one Northwestern engineering student. That kind of result is KID’s goal for the TEST program, and it’s why KID is currently expanding the TEST curriculum to make it more widely available. With the help and input of an advisory committee, including Ginzel and Stephen Carr, the associate dean for undergraduate engineering at Northwestern, the KID staff is hard at work. Its ultimate objective is to create a curriculum that includes full lesson plans on contemporary product safety issues, consumer safety laws and standards and ethics in engineering—along with a list of suggested projects such as those completed by students at Michigan and Northwestern.

To understand why these efforts are so important, one simply has to go back to the story of Danny. When Kolcraft was designing its Travel-Lite crib, its primary concern was creating a crib that was light enough to be easily carried. When the Michigan students designed their crib, safety was their primary concern. One cannot help but wonder how many lives could have been saved if the original designers had focused on safety.

For more information regarding the TEST program, contact Kids in Danger at or visit the Web site at

Nancy Cowles is executive director of Kids in Danger and Zachary Hill is an undergraduate student intern with KID from the University of Chicago.


WAVE OF INFLUENCE - By Jeffrey Selingo
ENGINEERING? ¡SÍ! - By Margaret Loftus
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TECH VIEW: Logging on to Class - By Mary Kathleen Flynn
A LESSON IN SAFETY - It took a tragedy to focus the engineering curriculum on safety in product design. - By Nancy Cowles and Zachary Hill
RESEARCH: The Challenge of Change - By Dave Woodall
ON CAMPUS: Mind Your Manners - By Lynne Shallcross
LAST WORD: State of Spending - By Wm. A. Wulf


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