It is important to replace a ski or snowboard helmet after any significant impact, as its ability to absorb energy will have been permanently reduced. Helmets should also be replaced if they show signs of physical ageing, such as a brittle shell or degraded foam liner. As a general guide, consider replacement after three to five seasons of use, but impact history and condition are the most important factors.

A ski helmet’s primary function is to manage the energy of an impact to protect your head. This is largely the work of the liner, the internal layer of foam that sits between the outer shell and your head. In most helmets, this liner is engineered to crush, crack and deform upon impact, absorbing and dissipating forces that would otherwise be transferred to the brain. But a helmet can only do this successfully once. After the material has compressed, it does not recover its original structure or protective qualities. This is vital to remember when determining when a helmet has reached the end of its functional life, whether through a single crash or the slow degradation of its materials through regular use over time.

The most critical rule for helmet safety is absolute: a helmet must be retired from use after it has sustained one significant impact. This applies whether you fall on a slope, collide with another person, or hit an object like a tree, rocks or a patch of ice. It also applies if you drop your helmet from a height onto a hard surface like concrete or asphalt. The force of the impact permanently compromises the helmet’s internal structure, even if there is no visible damage to the exterior shell.

Most ski helmets, including our freeride and all mountain helmets like the POC Obex and Fornix, use an EPS liner. EPS, or expanded polystyrene foam, consists of tiny beads fused together to create a structure that is very effective at absorbing energy. When subjected to an impact, the bonds between these beads break and the foam compresses, permanently deforming as energy is absorbed. A helmet with a compressed EPS liner has lost its ability to manage energy in that area and will offer substantially less protection in a future crash.

Some specialist helmets designed for the repetitive, lower-energy impacts common in ski racing use a different material. Helmets like the POC Artic SL and Skull Dura feature a multi-impact EPP liner. EPP, or expanded polypropylene, is more resilient and can deform to absorb an impact before returning to its original shape. This makes it suitable for gate impacts in training or racing. However, even a multi-impact EPP helmet must be inspected by a professional and likely replaced after a major crash, as its integrity can still be compromised by a sufficiently high force.

Even without a crash, a helmet's protective qualities diminish over time. The materials degrade due to environmental exposure and general use. A regular inspection of your helmet is essential to identify signs of ageing that indicate it is time for a replacement. A helmet used for 100 days in a season will age much faster than one used for ten, so a simple calendar-based replacement schedule is less reliable than a physical assessment.

The outer shell, typically made from a polycarbonate plastic, provides the first line of defence by distributing impact forces and resisting puncture. Over time, exposure to ultraviolet (UV) light from the sun makes this plastic brittle and weak. Look for faded or discoloured patches, chalkiness or fine surface cracks, all of which suggest the shell material is losing its structural integrity.

The foam liner is also susceptible to degradation. Heat, cold and contact with chemicals from sweat, hair products, or sunscreens can cause the foam to become brittle. A healthy liner feels firm but compliant. An ageing liner may start to flake, and begin to separate from the shell. You can gently press on the foam with your thumb; if it feels brittle or leaves a lasting indentation, its energy-absorbing properties are likely compromised.

But a helmet is made up of more than just a shell and liner. The retention system, including the straps and buckles, must be in working order to ensure a proper fit. Check straps for any fraying or tearing, and test the buckle to ensure it clicks shut securely and releases smoothly. A helmet that cannot be fastened correctly or does not stay in place cannot do its job.

While a general rule of replacing a helmet after three to five years broadly holds true, there are more factors than age at play, and therefore it is important to frequently check your helmet for signs of wear and tear. Material science continues to advance, but all protective equipment has a finite lifespan.

A regular, honest assessment of your helmet, goggles and body protectors is fundamental to taking a proactive approach to your safety on the mountain, ensuring the equipment you rely on is always ready to perform.