Kassel, Germany – The new face of trams in Berlin, Adelaide and Seattle relies on flame retardant flexible polyurethane components.
Hubner, which has been using the material for 30 years, makes the components. The company prefers polyurethane because it is 'highly robust and highly flexible.' The grade used is not truly elastic, it takes a few seconds for the foamed material to return to its original shape. This is important because it influences the Head Impact Criterion (HIC) in pedestrian safety.