Soft Foam Non Certified Helmets help reduce impacts when dropped from 2.8 Feet but if you drop them from the ASTM Multiple Impact Standard of 3.8 Feet a brain rattling and possible traumatic brain injury force of 380 G's impacts the head form. If you drop the soft foam helmet from the CPSC Single Impact test height of 7 feet, a possible death jolt of 800 G's enters the head form. A skateboard helmet's job is to reduce these impact forces to as little as possible. In order for a skate helmet to be ASTM or CPSC Certified they must reduce these impact forces to under 300 G's. The problem with soft foam (non certified) helmets is that the impact energy goes directly through the soft foam and impacts the head. 

The CPSC test height of 7 ft is the current helmet safety standard for skate and bike helmets.  Soft Foam helmets Fail this test. The ASTM multiple impact standard is 3.8 feet and soft foam helmets fail this test.

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