Hazard Classification of Seat Belt Pretensioners by UN Test 6(c)

The main aim of this work was to classify the three kinds of seat belt pretensioers by the UN test 6(c) according to the regulations of UN Model Regulations. The result of the first stage test shows that the sample B should be assigned to class 9, but the sample A and sample C should be assigned to 1.2G, which is out of the expected classification, 1.4G and class 9, in the Model Regulations. By improving the design of clamp devices of sample A and sample C, after the second stage test, the sample A meet the requirements of class 9, but the sample C should be assigned to 1.4G. By changing the geometrical arrangement of samples in the packaging and the design of the packaging, the third stage test has been performed. The sample C with the improved placement direction and the improved design of packaging were assigned to class 9. It is conclude that the hazard division/class of seat belt pretensioners can be assigned to 1.2G, not only 1.4G and class 9. The test results can provide efficient advice on the improvement of the safety design of seat belt pretensioners. The geometrical arrangement of the sample in the packaging and the design of the packaging have important effect on the hazard division/class of seat belt pretensioners.