Conflicting standards

DIN standards can have annoying side effects. Many of you will have experienced having a loop of your bathrobe get caught on the handle of a door when you pass from one room into another. At least this occurs here in Germany, since people still wear bathrobes and most doors have handles, not knobs.

DIN defines a standard average person of certain dimensions and proportions. When this person's arms are hanging, he (sorry, ladies) raises his hand slightly to (un)buckle his belt. Since he does this several times a day, if he gets lucky, this is considered to be a natural height for his hand to be at. Doors have to be opened and closed many times a day, even when your luck runs out. So the height of door handles and belts was standardized to the same value, for convenient living. This is why larger belt loops, as on a bathrobe, get caught on door handles.

The information about belts and doors comes from a fat DIN standard volume I once had to consult for some other reason. The justification for the slightly raised hand was a tad different from the one I just gave, but this is the way I was able to remember it. You sometimes get caught even when you're lucky.