I’m just posting these because they contain some good information.

Summary:

• A Washington State study (October 2002) of available data concluded that studded tires didn’t add enough safety to justify allowing them, given the damage they do to road surfaces, and recommended banning them – which would be a change from their current position of allowing them from November 1st to April 1st.
  • They acknowledged that there is a pavement wear issue for studded tires, but research this issue.
  • Studded tires are superior to other types of tires only on relatively smooth ice surfaces and snow near the freezing point. This is a narrow window of conditions that don’t occur very often.
• To my knowledge, Washington State did not act on this recommendation.

The source report and a later fact sheet are below.