What is the lifespan of a typical bicycle helmet?

The answer indicating a lifespan of 3 to 5 years for a typical bicycle helmet is based on several important factors related to helmet materials and performance. Over time, the protective foam inside the helmet can degrade due to a variety of elements, including exposure to sunlight, perspiration, and general wear and tear from regular use.

Most manufacturers recommend checking the helmet periodically for any signs of damage, such as cracks or dents, as these can significantly compromise the integrity of the helmet. Additionally, it's important to consider that helmets should be replaced sooner if they have been involved in an impact, as the protective capabilities can be diminished after such an event. Following the 3 to 5-year guideline helps ensure continued effectiveness in absorbing impacts and protecting the head.

The other options reflect either too short or too long lifespan estimates based on common understanding in safety practices. Helmets that are rated for shorter lifespans, such as under 3 years, may not account for the gradual wear from normal usage and environmental factors, while suggestions extending beyond 5 years could overlook the advancements in materials and safety standards that might necessitate more frequent replacements to ensure optimal protection.