Experimental analysis of airbag seam design: high-rate shear testing for skin abrasions

Abstract

Approximately 66 per cent of all airbag deployments in the USA result in at least one skin injury, with 47 per cent of these skin injuries attributed directly to the airbag deployment. The purpose of the present study was to evaluate the risk of skin abrasions from the airbag fabric seam design by using a new shear testing methodology. High-rate shear loading was performed with a pneumatic impactor that propelled a section of airbag fabric across porcine skin at 85 m/s. Twenty-seven tests (three control and 24 with fabric) were performed using eight different seam designs. A 40 cm × 10 cm section of airbag fabric with each seam was forced across a 5 cm × 5 cm section of fresh porcine skin that was acquired within 2 h post-mortem. No abrasions were observed in the three control tests, but abrasions were observed in all 24 of the tests conducted using airbag fabric. The unturned, sewn seam orientation resulted in significantly more severe abrasions than the woven, unturned seam orientation (P = 0.01). This new system and results illustrate that different seam designs can result in different skin abrasion risk. Moreover, the data show that severe abrasions can be caused by normal pressures well below the 1.75 MPa injury threshold previously published.