| Environment contributory factor | Severity of accident | Total | ||
| Fatal | Serious | Slight | ||
| Slippery road (not related to weather) | 0 | 13 | 102 | 115 |
| Slippery road (caused by weather) | 1 | 16 | 71 | 88 |
| Low bridge | 0 | 0 | 0 | 0 |
| High wind | 0 | 2 | 0 | 2 |
| Steep hill | 0 | 1 | 10 | 11 |
| LRT level crossing | 0 | 3 | 5 | 8 |
| Vision obscured by parked vehicle | 0 | 0 | 5 | 5 |
| Vision obscured by other stationary vehicle | 0 | 3 | 2 | 5 |
| Vision obscured by bus/PLB at bus/PLB stop | 1 | 3 | 6 | 10 |
| Vision obscured by queue of traffic | 0 | 0 | 0 | 0 |
| Vision obscured by sharp corner | 0 | 1 | 1 | 2 |
| Vision obscured on approaching crest of hill | 0 | 3 | 1 | 4 |
| Vision obscured by wall or bridge structure | 0 | 0 | 1 | 1 |
| Vision obscured by tree or bushes | 0 | 0 | 4 | 4 |
| Vision obscured by bus shelter | 0 | 0 | 0 | 0 |
| Vision obscured by advertisement sign | 0 | 0 | 0 | 0 |
| Vision obscured by other street fixtures | 0 | 0 | 0 | 0 |
| Vision obscured by hawker stall | 0 | 0 | 0 | 0 |
| Vision obscured by pedestrian | 0 | 0 | 0 | 0 |
| Vision obscured by other obstruction | 0 | 1 | 5 | 6 |
| Object or animal in road | 0 | 9 | 65 | 74 |
| Defective traffic signal | 0 | 0 | 7 | 7 |
| Potholes | 0 | 9 | 22 | 31 |
| Unreinstated trench | 0 | 2 | 5 | 7 |
| Obstructed road | 1 | 0 | 10 | 11 |
| Pedestrian negligence | 5 | 17 | 38 | 60 |