As more and more parents and grandparents are opting out of the use of rubber footed roller coasters as safety measures, some have questioned whether the technology is worth the risk.
In a blog post published today, the Rubber Footer Foundation, an organization dedicated to “reclaiming rubber playgrounds,” argues that rubber feet are “safe” and “efficient” but notes that “the risks of rubber feet in the wild are extremely low.”
To get a better idea of how much rubber feet can carry, the Foundation examined the data collected by the United States Centers for Disease Control and Prevention (CDC) on rubber feet collected during 2009-2015.
The CDC estimates that between 1.2 million and 2.4 million rubber feet were collected in the U.S. in 2015.
The Foundation found that a rubber foot has a circumference of about 3 inches (9 centimeters) and is made up of approximately 8 to 11 pieces.
Rubber feet are made up mainly of rubber cement, which is also found in cement blocks and concrete.
Rubber cement is often mixed with asphalt to make rubber feet, but the Foundation also found that asphalt was used to mix the cement with rubber cement.
As the Foundation notes, rubber feet “do not have any inherent strength,” but instead “are often made of a mix of rubber and other materials.”
So why do rubber feet carry more than the weight of their creators?
The Foundation points to a study conducted by a research team led by Robert and Joanna Epps of the University of Washington, who analyzed data from the CDC’s National Toxicology Program (NTP).
In their study, the Epps’ team identified 5 different types of rubber solids: water, dirt, asphalt, wood and glass.
The Epps’s team found that “there were 3 types of solids in each of the 5 types of feet.
Each type of solid had a different degree of hardness.”
The Eppses analyzed the surface properties of the solids that were being tested to see if they were more or less than the “average” hardness of rubber.
The average hardness of each type of rubber was determined using a series of tests that included a hardness test, an index of elasticity (e.g., weight per inch of length), and a coefficient of thermal expansion (e,g., the amount of energy a piece of rubber exerts on its surface).
The average value of the coefficient of elasticities of each rubber solid was also calculated.
After the Epps’ team used the average coefficient of the different types, they calculated the average number of pieces per foot of rubber that was carried.
They concluded that “rubber solids can carry far more than average.”
In their paper, the researchers also noted that “a single rubber foot could carry up to 3,000 pounds.”
The Foundation believes that the numbers of rubber parts per foot is just one of the many reasons why rubber feet cannot be safely used as safety devices.
In fact, Rubber Footers also point out that there is another reason why rubber footing is not a good idea: Rubber footing “causes a variety of problems.”
The Institute of Medicine (IOM) released a statement in July 2017 saying that rubber footers are “a dangerous substitute for other safety features, including seat belts, child restraints, child restraint gates, child safety seats, child-resistant vehicles, and child safety door locks.”
“Rubber feet, while an efficient and cost-effective method of safely and easily securing a child, are also inherently dangerous because they can carry dangerous amounts of rubber,” the IOM wrote.
The IOM added that rubber footing is “inherently dangerous because it can carry harmful amounts of metal and/or other materials,” and that “many types of metal are known to be highly dangerous.”
A rubber foot is also not as safe as other methods of securing a small child.
The Institute for Occupational Safety and Health (IOSHS) noted in its report on the IOSHS report, “It is not uncommon for children to be trapped and injured in rubber feet.
These injuries include severe fractures, dislocated limbs, and death.”
Rubber feet have been used in the United Kingdom, the Netherlands, and Australia, and are used in many other countries.
The National Council of State Boards of Education (NCSBE) and the UPCA (the American Rubber Construction Association) have issued warnings on rubber footings and other similar devices, noting that they are “not recommended for use in the home or other enclosed environments, and they are not appropriate for outdoor activities.”
The NCSBE also recommends that all children under age 16 use an “approved child restraint or child safety seat,” and states that “children under age six must wear a child safety belt or be restrained by a safety harness.”
“If you have any questions about this topic, please contact your local school or district or visit a local public safety department to see what type