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Safeguarding crushing points by limitation of forces
1Berufsgenossenschaftliches Institut für Arbeitsschutz, Sankt Augustin, Germany. Detlef.Mewes@hvbg.de
Abstract:
Limitation of forces can be a simple measure to safeguard crushing points at doors, machines, and vehicles. In this connection different standards define a threshold force value of 150 N. This widely accepted value refers to static forces only. The dynamic forces that arise from impact on a person are frequently ignored, although they are generally higher than the static forces. The article describes an instrument for the measurement of static and dynamic crushing forces. This instrument has a stiffness that approximates the average stiffness of human fingers as one of the most at-risk parts of the human body with regard to crushing injuries. Sensory tests were carried out to define dynamic forces considered admissible at crushing points.
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