Hearing loss analysis in full scale accident reconstruction

Holtz, Johannes; Müller, Gerd; Johannsen, Heiko; Büchner, Andreas; Wisch, Marcus; Huster, Daniel

Affiliations

¹Technische Universität Berlin, Chair of Naturalistic Driving Observation for Energetic Optimisation and Accident Avoidance, Gustav-Meyer-Allee 25, 13355 Berlin

²Technische Universität Berlin, Chair of Automotive Engineering, Gustav-Meyer-Allee 25, 13355 Berlin

³Medizinische Hochschule Hannover, Accident Research Unit, Carl-Neuberg-Str. 1, 30625 Hannover

⁴Medizinische Hochschule Hannover, German Hearing Centre Hanover, Karl-Wiechert-Allee 3, 30625 Hannover

⁵Federal Highway Research Institute (BASt), Referat F2, Brüderstraße 53, 51427 Bergisch Gladbach

Abstract and keywords

Airbags are, together with the three-point belt, the most effective passive safety equipment of vehicles. However, literature shows that sound pressure levels of up to 170 dB can occur during airbag deployment. A literature review revealed no systematic experimental data on possible hearing loss by airbag deployment, that also takes any other crash accompanied noise into account, such as deformation and impact noise. Also the rising number of airbags per vehicle resulting in a higher number of deployed airbags in an accident was not addressed with respect to hearing loss. Thus, an extensive test matrix of noise measurements during airbag deployments was conducted including onboard measuring during crashes and static measurements. Dynamic and static experiments with single and multiple airbag deployments were conducted. The results of this study show, that in the analyzed crash constellations the acoustic emission of the collision as well as the car deformation can trigger the stapedius reflex before the airbag deployment. The stapedius reflex protects the inner ear at least partially in case of dangerous sound levels. However, it seems that multiple airbag deployments in a short sequence pose a considerable risk for hearing impairments despite the fully contracted stapedius muscle. Further and in line with Price et al. (2013) it was found that the risk of hearing loss is lower with closed windows. The analysis of patient and accident data showed no link between airbag deployment and hearing loss. This might be caused by low case numbers of reported hearing loss problems up to now.

In conclusion the results show that a singular analysis of the sound pressure of airbag deployments without crash accompanied noises is not sufficient as the protective effect of the stapedius reflex is neglected. Still, successive airbag deployments in a short timeframe raise the risk of hearing loss. Further investigation on hearing impairment due to airbag deployment and triggering of the stapedius reflex is needed and the data acquisition of accidents and patients should consider hearing loss aspects.

Keywords: Airbag; hearing loss; accident reconstruction; stapedius reflex

Links

URL: http://indexsmart.mirasmart.com/26esv/PDFfiles/26ESV-000028.pdf

Cited Works (4)

Year	Entry
2017	Johannsen H, Krettek C, Hannawald L, Schaser K-D. Consideration of accident avoidance technology within GIDAS. In: Proceedings of the 25th International Technical Conference on the Enhanced Safety of Vehicles (ESV). June 5-8, 2017; Detroit, MI.
1998	Rouhana SW, Webb SR, Dunn VC. Investigation into the noise associated with airbag deployment, II: injury risk study using a mathematical model of the human ear. In: Proceedings of the 42nd Stapp Car Crash Conference. November 2-4, 1998; Tempa, AZ. Warrendale, PA: Society of Automotive Engineers:267-. SAE 983162.
1994	Rouhana SW, Webb SR, Wooley RG, McCleary JD, Wood FD, Salva DB. Investigation into the noise associated with air bag deployment, I: measurement technique and parameter study. In: Proceedings of the 38th Stapp Car Crash Conference. October 31–November 2, 1994; Fort Lauderdale, FL. Warrendale, PA: Society of Automotive Engineers:191-212. SAE 942218.
2003	Banglmaier RF, Rouhana SW. Investigation into the noise associated with airbag deployment, III: sound pressure level and auditory risk as a function of inflatable device. In: 47th Annual Proceedings, Association for the Advancement of Automotive Medicine (AAAM). September 22-24, 2003; Lisbon, Portugal.25-50.