Ah! get what you mean Bob, my Dad was on the berlin Airlift after the second bout of european unpleasantness, and they had an ongoing competition with the Yanks about how many Tons they moved, then someone pointed out that all tons are not equal!
You learn something everyday, the difference between long and short ton. We use tonne. The older hoists in the mill I had worked in were in labeled in American ton, for safety , we had to paint over and label in kilograms . We ended up with odd numbers instead of a simple 5 Ton.