This European Standard specifies: -- characteristics that suspension diaphragms achieves, together with applicable inspection and test methods to be carried out for verification; -- approval procedure to be implemented by the customer; -- guidelines for qualification of the product with specified requirements; -- quality monitoring of diaphragms in manufacture; -- supply requirements. This European Standard applies to suspension diaphragms designed to be fitted on railway vehicles and similar vehicles running on dedicated tracks with permanent guide systems, whatever the type of rail and the running surface. The European Standard does not detail the other components of pneumatic suspension assemblies or control systems such as air reservoirs, frames, stiffeners, emergency suspension systems or elastic supports (such as series springs), etc., which will affect the diaphragm performance.