Anthropomorphic Blast Test Device for Primary Blast Injury Risk Assessment.

Introduction: Blast overpressure health hazard assessment is required prior to fielding of weapon systems that produce blast overpressures that pose risk of auditory and nonauditory blast lung injuries. The anthropomorphic blast test device (ABTD) offers a single device solution for collection of both auditory and nonauditory data from a single blast at anthropometrically correct locations for injury risk assessment. It also allows for better replication of personnel positioning during weapons firings.

The Development of a Tympanic Membrane Model and Probabilistic Dose-Response Risk Assessment of Rupture Because of Blast.

Introduction: There is no dose-response model available for the assessment of the risk of tympanic membrane rupture (TMR), commonly known as eardrum rupture, from exposures to blast from nonlethal flashbangs, which can occur concurrently with temporary threshold shift. Therefore, the objective of this work was to develop a fast-running, lumped parameter model of the tympanic membrane (TM) with probabilistic dose-dependent prediction of injury risk.

Materials And Methods: The lumped parameter model was first benchmarked with a finite element model of the middle ear.

Incident Angle Correction Algorithm For Impulse Noise Injury Assessment.

Objectives: We developed an empirical algorithm to account for the effect of the change in the A-weighted sound exposure level (SELA) as a result of the change in angle of incidence (AoI) of the impulse noise on the prediction of hearing loss. The product is the upgraded software tool, Auditory 4.5 that incorporates the incident angle correction algorithm.

The Development of a Probabilistic Dose-Response for a Burn Injury Model.

Objective: The objective was to augment a burn injury model, BURNSIM, with probabilistic dose-response risk curves.

Methods: To develop the dose-response, we drew on a considerable amount of historical porcine burn injury data collected by U.S.

Impulse Noise Injury Model.

Objectives: The new Auditory 4.0 model has been developed for the assessment of auditory outcomes, expressed as temporary threshold shift (TTS) and permanent threshold shift (PTS), from exposures to impulse noise for unprotected ears, including the prediction of TTS recovery.

Methods: Auditory 4.

An Interim LAeq8 Criterion for Impulse Noise Injury.

Objectives: We present a method to account for the effects of the hearing protection devices (HPDs) for use with the 8 hours equivalent A-weighted energy (LAeq8) criterion. The method involves the calculation of the LAeq8 equivalent unprotected free-field dose (LAeq8EUFF), which is obtained by using the insertion loss (IL) data of the HPD together with free-field pressure measurements.

Methods: The method was validated against the historical the U.

Impulse noise injury prediction based on the cochlear energy.

The current impulse noise criteria for the protection against impulse noise injury do not incorporate an objective measure of hearing protection. A new biomechanically-based model has been developed based on improvement of the Auditory Hazard Assessment Algorithm for the Human (AHAAH) using the integrated cochlear energy (ICE) as the damage risk correlate (DRC). The model parameters have been corrected using the latest literature data.

Finite element modeling of blast lung injury in sheep.

A detailed 3D finite element model (FEM) of the sheep thorax was developed to predict heterogeneous and volumetric lung injury due to blast. A shared node mesh of the sheep thorax was constructed from a computed tomography (CT) scan of a sheep cadaver, and while most material properties were taken from literature, an elastic-plastic material model was used for the ribs based on three-point bending experiments performed on sheep rib specimens. Anesthetized sheep were blasted in an enclosure, and blast overpressure data were collected using the blast test device (BTD), while surface lung injury was quantified during necropsy.

A model for predicting primary blast lung injury.

Background: This article presents a model-based method for predicting primary blast injury. On the basis of the normalized work injury mechanism from previous work, this method presents a new model that accounts for the effects of blast orientation and species difference.

Methods: The analysis used test data from a series of extensive experimental studies sponsored by the US Army Medical Research and Materiel Command.

Evaluation of the biofidelity of FMVSS No. 218 injury criteria.

Objective: The biofidelity of the injury criteria used by Federal Motor Vehicle Safety Standards (FMVSS) No. 218 was examined against biomechanically based injury metrics.

Methods: An experimental method was developed to measure the helmet contact pressure distribution on a headform during an impact attenuation test.

Correlates to traumatic brain injury in nonhuman primates.

Background: Traumatic brain injury (TBI) is a major health problem, both in terms of the economic cost to society and the survivor's quality of life. The development of devices to protect against TBI requires criteria that relate observed injury to measurements of head kinematics. The objective of this study is to find the best statistical correlates to impact-induced TBI in nonhuman primates using a qualified, self-consistent set of historical kinematic and TBI data from impact tests on nonhuman primates.

A new biomechanically-based criterion for lateral skull fracture.

This work develops a skull fracture criterion for lateral impact-induced head injury using postmortem human subject tests, anatomical test device measurements, statistical analyses, and finite element modeling. It is shown that skull fracture correlates with the tensile strain in the compact tables of the cranial bone as calculated by the finite element model and that the Skull Fracture Correlate (SFC), the average acceleration over the HIC time interval, is the best predictor of skull fracture. For 15% or less probability of skull fracture the lateral skull fracture criterion is SFC < 120 g, which is the same as the frontal criterion derived earlier.