Coming from someone who operates emergency vehicles this is imperative and provides huge safety for all parties. If you hear sirens pull off the road until you can establish where the emergency vehicle is and proceed once they pass. There are many obstacles and deviations we as drivers have to make due to road conditions and actions of other drivers. My 2 cents tho is 80% of emergency vehicle accidents are caused by other vehicles and pedestrians not pulling over and stopping at the sound of a siren. They only pull over and stop (sometimes) when the emergency vehicle is extremely close to their proximity which drastically increases the danger to all 10 fold. In no way am i saying you or anyone else made a mistake. Please believe that. Im an instructor for DOT in regards to emergency vehicle operations, I teach classes year long to multiple agencies with multiple vehicle types and 15 years experience. Unfortunately the use of lights and sirens regardless increases danger to everyone involved no matter what you do as an operator. We just try to mitigate all hazards to the best of our ability and not cause another emergency on our way to an emergency. Im glad you ok mate, close call and hope everyone stays frosty out there!