Koroyd can use up to 78% of the material’s thickness for maximum energy absorption.
Because of this large compression volume, the structure can endure multiple impacts within one accident and still have material left to absorb energy.
For example, if you crash and roll on rocks, roots or tarmac, your head may hit the ground multiple times.
Important to note, after one accident involving a head impact, your Koroyd helmet (or any helmet) should be replaced and not used again.
Traditional materials stiffen during compression and solidify when up to 60% of the material is compressed, therefore reducing the thickness of the liner that can be utilised to absorb energy in an impact. This can result in forces being transferred to the head and brain.
Koroyd has significantly less elasticity than EPS foam (expanded polystyrene).
For sacrificial energy-absorbing materials, a lower elasticity may correlate with a lower risk of injury.
When the initial compression of any energy-absorbing material is unloaded (after an impact), it gives back a bit of energy due to elastic behaviour (rebound).
So even after an energy absorber has fully compressed to the point of densification, the absorbed energy can still pose a risk to the helmet wearer. This risk is greater with EPS foam.