More than a quarter of all passenger vehicles on the road in the United States have one or more underinflated tires-a condition that can lead to tread separation and blowouts. The National Highway Traffic and Safety Administration estimates that up to 10,000 injuries could be prevented annually if all vehicles had systems that warned drivers of underinflation. Frank Kelley of the University of Akron in Ohio and Barry Rosenbaum of Omnova Solutions, a chemical company in Fairlawn, OH, have devised a simple solution: a rubber material that changes color from black to red when tire temperatures rise above 77 C (underinflated tires get much hotter than properly inflated tires). The special rubber contains a material that changes color in response to temperature; a strip of the rubber could be built into the sidewalls of tires, visible as a red ring when things get too hot. The researchers have formed a company called TCS Polymers and hope to sell the rubber to the tire industry in three to five years.