Yeah it’s obvious emergency crews in London have been given some very stringent training on the use of sirens.
Only used for a short period on approach to junctions, turned off if it’s clear that traffic can’t create space for them (so they don’t just sit in traffic wailing away), alternating the siren tone after passing each junction so it’s clear to others you need to pay attention again as the vehicle has cleared an obstacle and is going to start accelerating.
They do an extremely good job of making sure that people know they’re there, without being unnecessarily obnoxious.
Only used for a short period on approach to junctions, turned off if it’s clear that traffic can’t create space for them (so they don’t just sit in traffic wailing away), alternating the siren tone after passing each junction so it’s clear to others you need to pay attention again as the vehicle has cleared an obstacle and is going to start accelerating.
They do an extremely good job of making sure that people know they’re there, without being unnecessarily obnoxious.