Upon the immediate approach of an emergency vehicle diplaying emergency lights, the driver of every other vehicle shall yield the right of way by moving to the right-hand edge or curb clear of any intersection and stop and remain stopped until the emergency vehicle passes. If an emergency vehicle is parked or stopped at the scene of an emergency and is displaying emergency red, white, or blue lights, traffic shall move to the right and stop. Once stopped, traffic may proceed with caution unless otherwise directed.