Date of download: 10/20/2017 Copyright © ASME. All rights reserved. From: Age Does Not Affect the Material Properties of Expanded Polystyrene Liners in Field-Used Bicycle Helmets J Biomech Eng. 2016;138(4):041005-041005-9. doi:10.1115/1.4032804 Figure Legend: Helmet types tested in this study (left to right: Traditional, Kids Visor, and BMX)

Date of download: 10/20/2017 Copyright © ASME. All rights reserved. From: Age Does Not Affect the Material Properties of Expanded Polystyrene Liners in Field-Used Bicycle Helmets J Biomech Eng. 2016;138(4):041005-041005-9. doi:10.1115/1.4032804 Figure Legend: Exemplar foam cores before and after testing (from Giro Torrent helmet)

Date of download: 10/20/2017 Copyright © ASME. All rights reserved. From: Age Does Not Affect the Material Properties of Expanded Polystyrene Liners in Field-Used Bicycle Helmets J Biomech Eng. 2016;138(4):041005-041005-9. doi:10.1115/1.4032804 Figure Legend: Test equipment. The foam core rested on top of a platform mounted on a load cell. The impactor was dropped from 749 mm above the platform onto the top of the foam core. An accelerometer was attached to the impactor.

Date of download: 10/20/2017 Copyright © ASME. All rights reserved. From: Age Does Not Affect the Material Properties of Expanded Polystyrene Liners in Field-Used Bicycle Helmets J Biomech Eng. 2016;138(4):041005-041005-9. doi:10.1115/1.4032804 Figure Legend: Exemplar data. The photographs show the sequence of foam compression at initial contact, at maximum compression, and after impact to a foam core. Representative plots for acceleration, force and crush versus time, and stress versus strain show that the foam cores exhibit typical impact responses for EPS foam. Initial contact occurred at time = 0 ms.

Date of download: 10/20/2017 Copyright © ASME. All rights reserved. From: Age Does Not Affect the Material Properties of Expanded Polystyrene Liners in Field-Used Bicycle Helmets J Biomech Eng. 2016;138(4):041005-041005-9. doi:10.1115/1.4032804 Figure Legend: Stress versus strain plots for all 63 foam cores. The response consists of three phases: elastic, plateau, and densification. Foam properties were calculated from the elastic (dashed black line on inset) and plateau (solid black line on inset) regions of a foam core's stress versus strain plot (thick gray line on inset).

Date of download: 10/20/2017 Copyright © ASME. All rights reserved. From: Age Does Not Affect the Material Properties of Expanded Polystyrene Liners in Field-Used Bicycle Helmets J Biomech Eng. 2016;138(4):041005-041005-9. doi:10.1115/1.4032804 Figure Legend: The variation in each of the six dependent variables with the year of manufacture. Helmet age was not significantly associated with any of the dependent variables.

Date of download: 10/20/2017 Copyright © ASME. All rights reserved. From: Age Does Not Affect the Material Properties of Expanded Polystyrene Liners in Field-Used Bicycle Helmets J Biomech Eng. 2016;138(4):041005-041005-9. doi:10.1115/1.4032804 Figure Legend: The variation in each dependent variable with foam core density. All dependent variables, except for yield strain (top left panel), increased significantly with density.

Date of download: 10/20/2017 Copyright © ASME. All rights reserved. From: Age Does Not Affect the Material Properties of Expanded Polystyrene Liners in Field-Used Bicycle Helmets J Biomech Eng. 2016;138(4):041005-041005-9. doi:10.1115/1.4032804 Figure Legend: As foam core density increased, peak foam core stress and strain decreased. Lower density cores exhibited all three phases of the typical stress–strain response (elastic, plateau, and densification). The lower density cores also displayed higher degrees of densification and wider plateaus.

Date of download: 10/20/2017 Copyright © ASME. All rights reserved. From: Age Does Not Affect the Material Properties of Expanded Polystyrene Liners in Field-Used Bicycle Helmets J Biomech Eng. 2016;138(4):041005-041005-9. doi:10.1115/1.4032804 Figure Legend: The peak acceleration (+) during impact decreased as the density of the foam core increased (shown by the exponential curve fit—thick solid line). As the foam core absorbed increasing amounts of energy, the more dense specimens had smaller increases in acceleration. This is depicted by the instantaneous acceleration corresponding to different levels of energy absorption: 1J (□), 3J (○), 5J (⋄), 6J (♦), 7J (∇), and 8J (▴).