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Development of new helmets to increase protection against severe injury/ head trauma Andrew McIntosh School of Safety of Risk and Safety Sciences, UNSW, Australia Acknowledgements to Dr. B Frechede, Ms. K Thai K and Mr D. Patton
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Development of new helmets to increase protection against severe injury/ head trauma Andrew McIntoshSchool of Safety of Risk and Safety Sciences, UNSW, Australia Acknowledgements to Dr. B Frechede, Ms. K Thai K and Mr D. Patton This project was funded by National Jockey Safety Committeeand the Rural Industries Research and Development Corporation
Current concerns • Head and spinal injury risks amongst jockeys have been identified as an important issue in the racing industry • Current jockey helmets are typically assessed against performance standards catering to all equestrian helmets and riding activities • Impacts in racing are at the severe end of the spectrum of possible equestrian impacts.
Current Helmet Standards • Jockeys and track work riders in NSW are currently required to wear helmets meeting one of the following standards: • AS/NZS 3838:2003 Helmets for horse-riding and horse related activities • ASTM F1163-01 Standard Specification for Headgear Used in Horse Sports and Horseback Riding • British Standard (BS) EN 1384/1996 (and onwards) Specification for helmets for equestrian activities
Current Performance Requirements • In the Australian Standard, the peak acceleration measured at the headform centre of mass must not exceed 300 Gravities. AS/NZS 3838 includes two impact test configurations: • 1.5 metre drop on to the flat anvil • 1.3 metre drop on to the “V” anvil • Helmets are conditioned (wet, cold etc) • The ASTM F1163 and EN 1384 helmets offer similar levels of protection. ASTM has a 300 G requirement for a 1.8 metre drop on to the flat anvil, and a 1.3 metre drop on to the hazard anvil. • EN 1384 specifies a 250 G requirement for a 1.5 metre free fall drop on to the flat anvil only.
Alternative Standard:High Impact Performance • In the European High Performance standard, helmet samples are exposed to 50˚C, -20˚C, UV radiation and water conditioning prior to testing. The Standard includes the following tests for impact energy attenuation and loading: • 2 metre drops on to the hazard and hemispherical anvils: 250G max. peak headform acceleration, >150G for max. 5 ms. • 3 metre drop on to the flat anvil: 250G max. peak headform acceleration, >150G for max. 5 ms. • 1 metre drop on to the flat anvil: 80G max. peak headform acceleration. • Resistance to penetration: 0.5 metre striker drop onto helmet, striker shall not leave an indentation on the test block. • Lateral crush: 180J lateral impact (7.5kg @ 2.45 metres), headform load shall not exceed 10kN. • Currently no helmet is made worldwide to meet this standard.
Aims • To assess the impact performance of current jockey helmets in standard laboratory tests • To assess whether any helmet met the requirements of the European High Performance Standard • To develop a prototype helmet to meet some performance requirements of the High Performance Standard
Methods • Guided free-fall impact tests were conducted using a rigid headform • Drop heights were from 1 to 2.5 m • Flat, hemispherical and V-anvils were used • The maximum headform acceleration was the main output of interest.
Helmets (examples) CHAMPION VENTAIR DELUXE JOCKEY HELMET $250-$280 Aus GPA JOCK-UP ONE JOCKEY HELMET $850-$900 Aus
Helmet tests on the flat anvil 500 400 300 Peak acceleration (G) 200 100 0 1.0 1.5 2.0 2.5 Drop height (m) CVA Deluxe LAS Country GPA Jockup 1 Aussie 21 Liner less New Derby Jockey GPA Jockup 3 Results – Flat Anvil
Helmet tests on the hemispherical and V anvils 500 400 300 Peak acceleration (G) 200 100 0 Hemispherical 1.5m Hemispherical 2m V-anvil 1.5m V-anvil 2m Drop configuration CVA Deluxe LAS Country GPA Jockup 1 Aussie 21 Linerless New Derby Jockey GPA Jockup 3 Results – Hemi and V anvils
Discussion • None of the current helmets meets the high performance standard requirements. • Helmets offer range of protection • Fair for 1 m drops • Good for 1.5 m drops • Fair for 2.5 m drops • Fair onto hemispherical and V-anvils • Retail price not correlated with performance
Prototype Development • Helmet improvements required to increase performance range up to 3 m drops and onto more ‘aggressive’ anvils. • Continue to target all performance requirements while minimising helmet mass • The resistance to penetration requirement leads to the helmet having a distinct shell, but can influence the energy attenuation potential.
Prototype Development • Material Testing • Computer Modelling • Material Testing • Prototype Testing
Example ResultsComputer Modelling Two different liner materialswere investigated. Varying thickness, density and combinations
Prototype testing Reference Helmet Prototype A Prototype B
Summary • Prototype helmet • Promising results demonstrate potential to reduce the severity of the head impact and injury potential for the higher energy impacts • There is still work to be done to meet the high standard requirements of low (1 m) and high (3 m) drop tests. • Potential improvements to be discussed with manufacturer • Further prototype development and refinement with manufacturer input.