One of the most commonly asked questions about bicycle helmets is,
When should I replace my helmet?
The general consensus among helmet manufacturers and cyclists is to replace the helmet after a crash or after three years of regular use.
Every helmet has a lifespan to provide maximum protection to your head. There are many factors that affect the lifespan of a helmet; such as exposure to sunlight, rain, temperature changes, regular cleaning and storing, and usage.
After a crash
If you fall and impacted the helmet, there is a very high chance it needs replacement. Have a thorough visual inspection of the shell. In many cases, the cracks are underneath the shell and not visible.
Take a close look inside the air vents from all angles. If you notice any visible cracks, regardless of their size, replace the helmet immediately.
After a crash, damages like cracks to the EPS, bumps on the polycarbonate outer shell, wear and tears marks, could be visible.Ulysse Daessle, MET Helmets
Changes in color and shape
Prolonged exposure to sun, rain, and over time can cause the helmet shell to be bubbly, crack or deform. For lighter color helmets, you’ll notice a significant fade in the colors.
If you noticed any missing small pieces from the helmet, such as on the retention system, there might already be damage done. Consider replacing the helmet.
Damage to the safety liners
The MIPS and SPIN safety liners absorb the energy upon impact and can degrade over time. Sometimes, even without the helmet taking a knock. If you notice any unusual movements in the liners, they could be damaged.
The reason is that helmet liners are made to absorb energy from impacts and they do this through their own degradation or destruction – like an airbag in a car. If the liner is compromised from an impact or other factors, it may not offer the full protective capability it was designed to provide.Eric Richter, Giro
More reading : MIPS Helmets Explained
Exposure to chemicals
Some cyclists use chemicals such as petroleum-based solvents to clean the helmet. They can damage the helmet shell’s protective capabilities, and sometimes, these damages are not visible.
Helmets are generally made of materials that can be damaged by many commonly-available cleaners. Petroleum-based solvents or cleaners are especially dangerous.Eric Richter, Giro
After three years
Even if the helmet is in a good condition with none of the signs mentioned above, consider replacing it after three years of regular use. You could probably stretch it to five years if it’s your spare helmet.
While this has nothing to do with helmet degradation or damage, a badly fitted helmet may not provide adequate protection during a fall. If you feel that the helmet is not snug against the head after you’ve tightened the retention system to the maximum, you’ll need a smaller size.
Besides, the helmet should sit squarely on the skull with no pressure points. Otherwise, the helmet’s shape might not be suitable for you. Perhaps you want to try other brands.
Bicycle helmet manufacturers’ recommendations
I took a deeper look at five of the leading bicycle helmet manufacturers’ recommendations. There is a general consensus that one should replace their helmet between three to five years of regular use.
Helmets are one of the most important pieces of protective equipment in gravity sports. We recommend helmets should be replaced every 1 – 5 years.POC Sports
We advise replacing it after approximately 3 years from the original date of purchase.Kask
When not being used for a period of time we recommend that the helmet be placed back into its box or case and stored in a cool, dry place.Giro
Bell has a general recommendation of replacing your helmet every three (3) years.Bell
Life of a helmet should not exceed three to five years of normal use.MET Helmets
Helmets have a limited lifespan in use and should be replaced when they show obvious signs of wear. Additionally, helmet parts lose strength over time, so even if the helmet has not been impacted or damaged, we recommend replacing it after three years.Bontrager