In the UK, the term "scale" is rarely used with a gauge identifier. If you talled about "OO scale" people would look at you over the tops of their spectacles. :-D If the scale was mentioned it would be "4mm" etc.
I say "rarely" because Airfix used to label their lineside accessory kits as "OO/HO scale", and happily ignored the fact that OO and HO were two different scales that simply did not go well together!
LOL Excellent!