Recently I came across a page on Rays Wheels. Below is a figure illustrating how Rays developed their own standards (JWL+R) on top of JWL.
For example, fatigue testing cycles have been drastically increased. And in addition to the JWL-standard 13 deg. impact test, JWL+R drops a 2200lb weight
at a 90 deg. angle from ~5.5". And then the same wheel
is used for an additional near 1 million cycles
of radial endurance testing