Life Cycle Assessment on Autoliv's Driver Airbag

Abstract

This master’s thesis is an evaluation of the environmental performance of a driver airbag, produced by Autoliv Sverige AB, by using cradle-to-grave Life Cycle Assessment methodology. The studied airbag is a pyrotechnical airbag, thus representing 80% of types of airbag produced by Autoliv. Pyrotechnical airbags operate solely by the deployment of chemical mixtures, as opposed to hybrid airbags which also used compressed nitrogen. The study includes data collection by surveying the companies throughout the supply chain and conducting literature review for general data to supplement the site-specific data; calculating the environmental parameters; analyzing the results by locating dominant substances and processes; and comparing the environmental load of the airbag package with a complete car. The results of this LCA study shows that life cycle of one unit driver airbag may cause global warming equivalent to 31.78 kg of CO2, acidification equivalent to 50.42 g of SO2, eutrophication equivalent to 39.35 g of NOx, resource depletion of 1.52E-10 g/reservebase, toxicological impact to aquatic equivalents to 947.73 m3 of water, and 67.78 g of contaminated bodyweight for human toxicity. The entire life cycle for one airbag also generates 4.93 kg waste and consumes 569.56 MJ energy and 79.24 kg water. Dominant processes in the whole life cycle are steel production due to its high water and energy consumption, polyamide production due to its high energy consumption and various emissions, and the use phase due to its high fuel consumption. Some materials in the airbag system should be avoided for environmental consideration, mainly by reducing the weight of steel components and polyamide content in airbag module. In particular, zinc coating, used in steel production, is associated with a relatively large environmental loads. Further research should be directed to more finely detect areas of improvement with regard to weight reduction and raw material selection.