Because it is not only the specs in the US that are considered when they build these ROPS. If you measure them and check all the US specs you may find that some are surpassed to satisfy a spec from another country.
If you like I will say you are entirely right! I hope this makes you feel better. I think the original question was "why are they built so high"?
Dave G.
KiotiDave
I don't know what could be relevant to the thread, as far as surpassing US specs. other than your apparently suggesting that a ROPS may be built higher than is specified by the united states government, (which would not necessarily then met our standard, which calls for them to already be very high), so that they can also meet some other specifications.
Note the inside dimension in the OSHA regulation is not variable, it's not a minimum number that allows for additional height, it's specified.
Can you provide any actual evidence of additional height, that goes beyond US standards, on any equipment sold in the US?
It's important if it would change the fact that they do not fit in a 7' opening, (the most common gripe).
If you could show me where a tractor would have fit in a 7' opening, except the manufacturer decided to save a buck, and make the ROPS higher, so they could also sell it somewhere else, I think that would make an interesting thread.