Levels of risk (San Francisco walks edition; log scale of micromorts per hour): ⚪ 0.05 µm/h • Sitting at home reading about walking in SF. • Same as baseline indoor existence. ⚪ 0.1 µm/h • Morning stroll around the Palace of Fine Arts or Crissy Field, broad daylight, low traffic. ⚪ 0.2 µm/h • Golden Gate Park, paved paths, daytime weekends, with other pedestrians. 🟢 0.3 µm/h • Presidio trails, clear weather, light tourist traffic. • Slight hill exposure; minimal vehicle contact. 🟢 0.5 µm/h • Marina Green → Fort Mason walkway, windy afternoon, occasional cyclists. 🟢 0.8 µm/h • Inner Sunset or Noe Valley neighborhood walks, daytime errands. 🟡 1 µm/h • Haight-Ashbury or Mission Dolores corridors mid-afternoon. Normal crosswalk traffic. 🟡 2 µm/h • Downtown / Union Square during lunch rush, dense crowds + vehicle exposure. 🟡 3 µm/h • Market Street early evening, light rain, crossing many intersections. 🟠 5 µm/h • Civic Center or SoMa after dusk, mixed foot and car flow, poor lighting. 🟠 8 µm/h • Tenderloin edge around 8 p.m., walking briskly, valuables visible. 🟠 12 µm/h • 6th Street corridor, solo, headphones in, after dark. 🔴 20 µm/h • Tenderloin core after midnight, visibly carrying electronics, some street drug activity. 🔴 30 µm/h • Bayview industrial zones late night, minimal lighting or people around. 🔴 50 µm/h • Mission / Civic Center past 2 a.m., visibly intoxicated, alone. • Comparable to an hour of highway motorcycling. ⚫ 100 µm/h • Wandering impaired through active fentanyl trade zones at 3 a.m. • Real probability of assault or medical collapse. ⚫ 300 µm/h • Same as above + overt confrontation or entering traffic lanes. • Equivalent to climbing a Himalayan route without ropes—for one hour. (By chat)