Technical Standards EUWA ES-3.06 Safety Recommendations in Connection with Wear on Rim Flanges of Vehicle Wheels.

This specification covers safety recommendations for wheels of cars, estate
cars, vans and commercial vehicles made of steel or light metal in connection
with the wear on rim flanges under extreme conditions as for example sea
atmosphere, winter salt resp. granulate, sand or dirt influence etc.
This may also indicate overload or underinflation, which in any case must be
excluded.
An example of such wear on the rim flanges of a 15° D.C. wheel see fig. 1 on
page 2.

EUWA ES-3.06 Safety Recommendations in Connection with Wear on Rim Flanges of Vehicle Wheels.