EPS has been used in bicycle helmet manufacturing since the 1970s. Whilst new material innovations are emerging in some performance aspects of cycling such as downhill mountain biking, these come at a premium and EPS remains the staple material in adult leisure and commuter and children’s helmets.
The study was undertaken during the height of the Covid pandemic, when increased anxiety over public transport and a surge in exercise fueled a dramatic increase in bicycle and accessory sales for adults and children alike.
The testing undertaken for the study used standardised testing equipment and impact assessments to determine the performance of the EPS samples. Current cycle safety standards require a helmet to decelerate / absorb sufficient energy to prevent the transmission of damaging levels of impact energy to the user. The standard impact test a cycle helmet must pass is two spaced single impacts. It is assumed that the helmet is discarded after the simulated crash. When examining everyday impacts, detrimental damage accumulates unpredictably, reducing a cycle helmet's overall capacity to protect from a significant impact.
This study tested the performance degradation generated by small impacts (to mimic everyday knocks, blows and drops to the helmet) to the overall impact performing properties of the EPS. The study concluded that surprisingly little damage could be inflicted to an EPS helmet before it was unable to perform to the required legal cycle safety standard, EN1078.
The same test was performed on one of the new materials, Enkayse, developed by British manufacturer Hedkayse, that is now being used in head protection. This found that this new material does not diminish the safety properties of the head protection after multiple impacts and continued to provide sufficient protection.
Hedkayse approached Loughborough University Sports Technology Institute to investigate the reliability of cycle helmet materials and Sports Technology Programme Director Dr Paul Sherratt introduced final year student Josh Jones as an ideal match to undertake the study.
George Fox, Hedkayse co-founder commented:
“Engaging with Loughborough University has been instrumental in providing unbiased points of view towards analysing material performances. We have been very impressed with the thoroughness of the project which has since kickstarted further studies with undergraduate and postgraduate students ranging from ergonomic developments, to electronics and aerodynamic form studies.”
Paul Sherratt added:
“We actively encourage student interaction with real businesses; live interaction gives purpose to projects. The opportunity to engage with progressive sports brands such as Hedkayse gives students an invaluable opportunity to input into emerging innovations which have the potential to challenge the status quo. With the innovation of new ways to protect your head with inflatable airbags such as Hovding, and new material technologies such as Enkayse that can withstand multiple impacts, this study has revealed some thought-provoking issues.”