I’m not even mostly American (technically I am) but I’ve worked on your bloody EHR systems. And even I know that specifying colours is generally only found in aviation and other transportation regs.

Which makes sense as even a “Code Blue” is not universal.

But even in countries where there is a unified universal health system, such as Britain’s NHS or my own Ireland’s HSE, federal/national governmental regs don’t get that specific and each Trust or Hospital Group has substantial control over these sorts of things.