In Finland, the Traffic Accident Investigation Teams investigate reported road accidents in which an airbag(s) has deployed due to an accident or while driving. The aim is to produce information on airbag performance in traffic accidents, and also assess its merits and adverse effects. The investigation still goes on with new cases. This report contains 56 accidents investigated during 1993-95, in which a total of 92 vehicles and 149 people were involved. 59 passenger cars were equipped with at least one airbag. 57 occupants were sitting in front of the deploying airbag, 5 (9%) of them injured seriously, 21 (37%) slightly and 31 (54%) escaped all injuries altogether. The investigation teams estimate that seven occupants survived death in these accidents as a direct result of deploying airbags, in 18 cases it prevented injuries altogether while in further 18 cases injuries were less severe. An airbag had no beneficial effect at all in 13 cases; in those cases one person was injured seriously, one slightly and the rest suffered no injuries at all. The cars in which the airbag had deployed were divided into 14 makes and 25 models. That is why the small sample is not sufficient to study the airbag performance by make and model. 36 (65%) of the cars were under one year of age. According to the VdS-classification, in 18 (33%) cases the damage to the car with an airbag was minor. There were no crashes where an airbag had inflated due to impact from a direction other than head-on (±33%) or without impact at all. There were four cases reported to the teams as cases in which the airbag should have been deployed. However, investigation reconstructions concluded that in fact no one should have been deployed. The impact speed of cars fitted with airbags was 50 km/h or less in 29 (52%) crashes, and with one exception, the speed of all was 80 km/h or less. In 21 (38%) cases the energy of impact corresponded to a crash into an obstacle at the speed of 20 km/h (EES). The change of velocity (delta v) was 10 km/h or less in 16 (30%) crashes and 30 km/h or less in 42 (80%) cases. 34 (60%) out of 57 occupants facing the airbag were belted and 23 (40%) were not. 21 (62%) of those who wore safety belt and 10 (43%) who did not escaped all injuries. 18 (51%) of those belted and 9 (41%) of not belted sustained no airbag orginated bruises or abrasion. 15 front seat passengers in cars fitted with airbags had no passenger side airbag. Three of them were injured slightly and 12 escaped injuries. In the investigated accidents, airbags deployed in an unoccupied seat in six crashes. In addition to this, the investigation teams estimated that in 13 cases the airbag did not have any effect because impacts were so light or change of velocity was minor. This totals 19 unnecessary deployments. Consideration of the effect of safety belt tensioners is excluded from this summary. However, the belt tensioners were installed in both front seats of 53 cars. On the right side they triggered 36 (68%) times without a passenger. In all eight cases, in which the airbag on the right side seat deployed, the windshield also broke up, in four of them it was exclusively the airbag or the cover of its protective box that broke the shield. Estimates made by people seated in front of the airbag and also by the investigation teams regarding the protective influences of airbags were identical in 32 (64%) cases. Nearly half (25, 47%) of the people seated in front of the airbag did not notice the deployment of the airbag. "Clouds of airbag powder" and fear of fire were the most frequent observations. 16 people wore eyeglasses and none broke up, but in some cases a few of them fell off the face. In approximately half (27, 48%) of the cars the airbag deployment did not cause any injury. Mostly the injuries caused by airbag were slight abrasions and bruises at the areas around arms, chests and face. In no crashes did airbags increase injuries substantially. In conclusion this report confirms that airbag and belt tensioners together form an effective protection system which is worth supporting. However, on the basis of 56 investigated cas the report suggests some improvements to the restraints in order to increase protection and cost-benefit value. Increased number of airbags should not reduce the wearing of safety belts. It should be stressed in public information that an airbag is not an alternative to a safety belt but it is supplementary. The trigger sensors of airbags and tensioners must be further developed so that they are abl to recognize the unoccupied seat. Furthermore, they should function only when they are needed (impact threshold). The belt's reel lock and tensioning mechanism should be further developed so that they trigger only for the safety purposes. Furthermore the function should be easily checkable without any difficult dismantling work. The passenger side airbag should be redesigned so that deployment doesn't break the windscreen or cause any other damage. Airbags must be marked clearly in standardised manner, it should also include those already in use. The airbag for the front passenger must be clearly marked with the warning label forbidding the use of a childrens' seat or placing of an infant or toddler in the front seat. Children's seats must be provided with labels warning of the dangers of airbags. (A)
Samenvatting