traffic lights at fire stations

if they put a traffic light at a fire station or ambulance station -
maybe it should be totally off - then flashing green and yellow - then
flashing yellow and red - and then solid red - 11/10/2025

maybe they typically in the USA are - flashing green - then flashing
yellow - then red - which isnt a bad scheme

maybe the best scheme would be - flashing green usually - then on
activation for an emergency departure - go to flashing green and
yellow - then flashing yellow - then red

or maybe - (off) - then - flashing green - to - flashing green and
yellow - then - flashing yellow and red - then solid red

seems that going from 'off to green to yellow to red' might not catch
anyones attention - especially at night

is there are any rule about this?