Simple answer: >30 degrees.
Long answer Journal of Transport & Health ∎ (∎∎∎∎) ∎∎∎–∎∎∎ (sic!).
CC-BY-NC Science Surf , accessed 03.04.2026, click to save as PDF
Simple answer: >30 degrees.
Long answer Journal of Transport & Health ∎ (∎∎∎∎) ∎∎∎–∎∎∎ (sic!).