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There are a number of major motorcycle helmet standards, e.g. AS/NZS 1698, DOT, JIS T 8133, Snell M2010 and UN/ECE 22. With international trade agreements, on-line purchasing, and motorcycling growth there is a need to assess whether there is scope for harmonising motorcycle helmet standards as well as specialising standards for specific environmen...
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Citations
... The fidelity of physical properties of headforms is crucial to ensure that laboratory tests adequately predict mechanical measures of injury that are expected in realworld collisions under the same impact conditions. Current helmet standards use translational acceleration of the headform to assess the performance of helmets (McIntosh and Grzebieta, 2013;Becker et al., 2015). However, motivated by extensive biomechanics evidence and the development of new helmet technologies Kurt et al., 2017;Bliven et al., 2019;Khosroshahi et al., 2019;Siegkas et al., 2019), new test methods are emerging that require measuring both translational and rotational motions of the headform to evaluate injury criteria, such as peak rotational acceleration and velocity. ...
... We used both kinematics-based and tissue-based injury metrics to evaluate head injury. PTA is a kinematics-based injury metric that has been suggested for predicting the risk of skull fractures and focal injuries (Gurdjian et al., 1966;Allsop et al., 1988), and it is used in all helmet standards (McIntosh and Grzebieta, 2013;Whyte et al., 2019). The Cellbond headform produced higher PTAs in rear and side impacts but similar PTAs in other impacts compared to the HIII headform. ...
New oblique impact methods for evaluating head injury mitigation effects of helmets are emerging, which mandate measuring both translational and rotational kinematics of the headform. These methods need headforms with biofidelic mass, moments of inertia (MoIs), and coefficient of friction (CoF). To fulfill this need, working group 11 of the European standardization head protection committee (CEN/TC158) has been working on the development of a new headform with realistic MoIs and CoF, based on recent biomechanics research on the human head. In this study, we used a version of this headform (Cellbond) to test a motorcycle helmet under the oblique impact at 8 m/s at five different locations. We also used the Hybrid III headform, which is commonly used in the helmet oblique impact. We tested whether there is a difference between the predictions of the headforms in terms of injury metrics based on head kinematics, including peak translational and rotational acceleration, peak rotational velocity, and BrIC (brain injury criterion). We also used the Imperial College finite element model of the human head to predict the strain and strain rate across the brain and tested whether there is a difference between the headforms in terms of the predicted strain and strain rate. We found that the Cellbond headform produced similar or higher peak translational accelerations depending on the impact location (−3.2% in the front-side impact to 24.3% in the rear impact). The Cellbond headform, however, produced significantly lower peak rotational acceleration (−41.8% in a rear impact to −62.7% in a side impact), peak rotational velocity (−29.5% in a side impact to −47.6% in a rear impact), and BrIC (−29% in a rear-side impact to −45.3% in a rear impact). The 90th percentile values of the maximum brain strain and strain rate were also significantly lower using this headform. Our results suggest that MoIs and CoF have significant effects on headform rotational kinematics, and consequently brain deformation, during the helmeted oblique impact. Future helmet standards and rating methods should use headforms with realistic MoIs and CoF (e.g., the Cellbond headform) to ensure more accurate representation of the head in laboratory impact tests.
... The objective of a motorcycle helmet standard is to ensure a minimum level of head protection under some specific test conditions. However, methods and requirements vary from one standard to another and, therefore, the performance against impact of motorcyclist helmets is influenced by the requirements included in each standard [9,10]. ...
Regulation ECE-22.05/06 does not require a helmet penetration test. Penetration testing is controversial since it has been shown that it may cause the helmet to behave in a non-desirable stiff way in real-world crashes. This study aimed to assess the effect of the penetration test in the impact performance of helmets. Twenty full-face motorcycle helmets were penetration tested at multiple locations of the helmet shell. Then, 10 helmets were selected and split into two groups (hard shell and soft shell) depending on the results of the penetration tests. These 10 helmets were then drop tested at front, lateral, and top areas at two different impact speeds (5 m/s and 8.2 m/s) to assess their impact performance against head injuries. The statistical analyses did not show any significant difference between the two groups (hard/soft shell) at 5 m/s. Similar results were observed at 8.2 m/s, except for the top area of the helmet in which the peak linear acceleration was significantly higher for the soft shell group than for the hard shell group (230 ± 12 g vs. 211 ± 11 g; p-value = 0.038). The results of this study suggest that a stiffer shell does not necessarily cause helmets to behave in a stiffer way when striking rigid flat surfaces. These experiments also showed that hard shell helmets can provide better protection at higher impact speeds without damaging helmet performance at lower impact speeds.
... However, wearing an MSH while riding a motorcycle is influenced by various factors, such as the existing traffic rules, environmental factors, law enforcement by the police, social norms, and the community's common beliefs (Ghasemzadeh et al. 2017). An Australian report on motorcycle helmet standards mentioned that MSHs were effective in reducing the risk of death by 42% and head injury by 69%; however, mild traumatic brain injury appears to be the prevalent form of injury suffered by helmeted motorcyclists (McIntosh and Grzebieta 2013). The need to investigate the quality of MSHs in terms of compliance with MSH standard regulations was suggested in Indonesia because the study found very little safety consciousness among the riders and a general lack of understanding concerning MSH use (Conrad et al. 1996). ...
... These findings were a preliminary attempt to determine the duration of the years of MSH usage but, remarkably, they also suggest that a more in-depth study should be carried out to determine the optimum number of years an MSH should be used to prevent overuse, which might increase the risk of head injury among occupational motorcyclists. As suggested by McIntosh and Grzebieta (2013), riders of small powered motorcycles in hot and humid climates might have a helmet certified to a different part of a common standard compared to high-powered motorcycle riders because both have different needs. ...
Objective: The objective of this study was to determine the proportion of motorcycle safety helmets (MSHs) used by postal delivery riders (PDRs) that comply with the Standards and Industrial Research Institute of Malaysia’s (SIRIM) MSH standard guidelines and identify factors that contribute toward compliance of used MSHs with the standards.
Methods: The presence of SIRIM certification label, the status of MSH, type of chinstrap, MSH crash history, and duration of MSH use were observed. The dependent variable was the results of the SIRIM testing procedures (SIRIM tests). MSHs that passed the SIRIM tests were considered “standard certified” MSHs.
Results: The odds of the complimentary MSHs passing all of the SIRIM tests were 3.7 times the odds of the self-purchased MSHs passing the tests. The odds of MSHs with the SIRIM certification label passing all of the SIRIM tests were 24.2 times the odds of MSHs without the SIRIM certification label, and the odds of MSHs used <3 years passing the SIRIM tests were 3.75 times the odds of the MSHs used ≥3.8 years.
Conclusion: PDRs provided with complimentary MSHs with the SIRIM certification label by the employer for their daily delivery routines and duration of MSH used for less than 3 years were found to be safe MSHs for male occupational riders in Malaysia.
... Hence, the authors decided to develop their own helmet finite element model. Each helmet on the market must fulfil the regulations, which depends on the territory where the helmet is sold (see McIntosh andGrzebieta, 2013 or Smith andKebschull, 2016). Since the regulations are quite similar, the authors decided to validate the developed helmet model based on the European standard Regulation 22.05 (United Nations, 2002). ...
Motorcycle riders belong to the group of so-called vulnerable road users, for whom protection against an impact is an important issue due to the multi-directional loading and the complex kinematics after the impact. Virtual biomechanical human body models play an important role to assess injuries, especially for such complex scenarios. The major motorcycle riders' personal protective equipment is the helmet. Several authors developed their own helmet model taking into account various helmet details. The presented work concerns a simple finite element helmet model development and validation according to the ECE Regulation 22.05. The helmet is validated in several impact scenarios coupling the headform impactor to the helmet and throwing it to the defined anvils. The advantage of the developed helmet is the low calculation time step by fulfilling the regulation. It can be coupled to the human body model easily without decreasing the global calculation time step.
... Hence, the authors decided to develop their own helmet finite element model. Each helmet on the market must fulfil the regulations, which depends on the territory where the helmet is sold (see McIntosh andGrzebieta, 2013 or Smith andKebschull, 2016). Since the regulations are quite similar, the authors decided to validate the developed helmet model based on the European standard Regulation 22.05 (United Nations, 2002). ...
Motorcycle riders belong to the group of so called vulnerable road users, which protection against impact is an issue due to the multi-directional loading and complex kinematics due to the impact. Virtual biomechanical human body models play an important role to assess injuries especially for such complex scenarios. The major motorcycle rider personal protective equipment is the helmet. The present work concerns the simple helmet finite element model development and validation to be coupled to the existing human body model for motorcycle riders’ safety assessment. The advantage of the helmet is the low calculation time step by fulfilling the ECE R22.05 regulation.
