Maybe I'm not looking at the right pictures, because a quick Google Images search for "uk firefighters" and "us firefighters", I see no functional difference in

Maybe I'm not looking at the right pictures, because a quick Google Images search for "uk firefighters" and "us firefighters", I see no functional difference in what they're wearing, and the only difference in the firetrucks is that American firetrucks are massive bricks and UK firetrucks are either a European-style truck that looks basically the same as a US-style truck or are a Ford Transit van with some hoses. The helmets look exactly the same except the ones in the UK don't have brims on the back.