| | Attribute | Index | Safety grade | | Dangerous (grade 1) | Less dangerous (grade 2) | Less safe (grade 3) | Safe (grade 4) |
| | Traffic environment | Time to collision (s) | (1, 2) | (2, 3) | (3, 4) | (4, 5) | | speed (km/h) | (80, 100) | (60, 80) | (40, 60) | (20, 40) | | Visibility (m) | (0, 50) | (50, 100) | (100, 150) | (150, 200) | | Pavement slippery (adhesion coefficient) | (0.1, 0.3) | (0.3, 0.5) | (0.5, 0.7) | (0.7, 0.9) | | Driver | Driving intention | Accelerate | Constant speed | Lane change | Decelerate | | Driver fatigue | (0, 3) | (3, 6) | (6, 9) | (9, 12) |
|
|
