Materials — DOME

An overview of helmet materials.

Think back to humans first realizing that protecting the head might be a worthwhile effort and imagine what they might have used. It’s hard to imagine all of the possibilities. Over the ages, a lot of materials have likely been considered or even tried that we may not know about. While we may not be able to cover every helmet material that’s ever been tried, we’ve put together this list of the most common and relevant materials over time. With information on their strengths, weaknesses and modern relevance. All for your consideration.

Acrylonitrile Butadiene Styrene (ABS)

Acrylonitrile butadiene styrene (ABS) is a thermoplastic widely used to construct the outer shells of some helmets.

Air (Bladders)

Air-filled bladders have been used in helmet liners (particularly football helmets) since the 1970s.

Composites

Lightweight and strong, composite materials—often a combination of epoxy reinforced by carbon, glass or Kevlar fibers—are used to fabricate high-end helmet shells.

Cork

Cork is the bark tissue harvested from the bark of cork oak trees. Cork, like pith, was a precursor to the crushable foams used in helmet liners today.

metal

Corrugated Fiber Board

Similar to the material used to create cardboard shipping containers, corrugated fiber- board has been used (in a few cases) to create a crushable helmet liner.

wood

E-PLA (Expanded Polyactic Acid)

Expanded polyactic acid (or “E-PLA”) is a crushable foam that can be used in helmet liners. It functions similarly to EPS, but whereas EPS is a petroleum-based product, E-PLA is plant-based.

Expanded Polypropylene (EPP)

Expanded polypropylene (EPP) is a resilient foam that can regain its shape following an impact. It can be found in some helmets that are labeled as “multi-impact”, though this label can be misleading since no helmet can guarantee the same degree of impact protection when repeatedly impacted at the same location.

Expanded Polystyrene (EPS)

Expanded polystyrene (EPS) is a crushable foam used in helmet liners. Cost effective, lightweight and very good at reducing impact energy, EPS is found in many helmets.

Koroyd™

Koroyd™ is a material composed of co-polymer tubes that are thermowelded together into a single mass. The material can be shaped into helmet liners, where it helps manage impact energy.

Leather

Used as a sort of second skin, leather was incorporated in helmet shells for millenia.

leather

Metal

Metals have been used extensively in helmets for about five thousand years and were still in active use (in military applications), well into the 20th century.

metal

Pith

Pith is a crushable material harvested from the stems of vascular plans. It was utilized as a helmet liner material from the 1800’s through to about 1940.

Polycarbonate

Polycarbonate, like ABS, is a thermoplastic widely used to construct helmet shells.

Vinyl Nitrile

Vinyl nitrile is a resilient foam that can be used as a liner material in helmets designed to withstand more than a single impact.

Zorbium®

Zorbium is said to attenuate energy from both low and high-energy impacts. It is also said to provide multi-impact protection.