Funny, I remember the TUV being criticized by an Australian car magazine
because they don't check safety issues like: a motorcycle with a chain so
rusted many links were seized. Ever broken a chain on a bike? When this was
pointed out by the writer, the TUV man insisted that it was not on his
list.

Basically, the TUV is a bureaucracy, and as such is unlikely to have
sensible requirements. Because the TUV doesn't approve something doesn't
mean it's not good. TUV approval doesn't mean an item is safe, merely that
the manufacturer has paid the TUV to have a brief glance at a vehicle
fitted with said item and check it off on the "approved" list.