Study: Foam meant to protect can harm

NEW YORK, Aug. 9 (UPI) -- Soft foam used in helmets and body armor can cause just as much injury to the wearer under impact or explosion loads as harder materials, U.S. researchers say.

In a counter-intuitive finding, scientists at New York University say the foam, which will absorb damage when compressed slowly, can inflict as much injury as a hard object when struck at high speeds, a university release said.

University materials scientists say the findings mean speed of impact is a factor manufacturers should take into account when selecting protective materials, whether for sports equipment, military armor, car interiors or submarines.

The team used a high-speed camera to take about 7,000 images per second of bones under high load rates, simulating a blow to the body or the impact from a nearby bomb blast among other conditions.

The researchers say the tests could change the methods of diagnosis for soldiers and football players whose injuries aren't immediately detectable but whose symptoms evolve over time.