Speed clearly plays a role in collisions that occur on our roads, but the extent to which speed contributes to accidents is often disputed. The DfT has recently published work on this subject titled ‘The Characteristics of Speed-related Collisions‘ which tries to understand to what extent speed contributes to collisions and under what circumstances drivers make inappropriate speed choices.
One important finding is that the extent of speeding is often under reported. When ‘On The Spot’ (OTS) data (in-depth data collected from a sample of collisions) is compared to Stats19 (collected by the police) the following was found:
- Excess speed was recorded for 4.7% of vehicles in OTS based on the contributory factors. This compares with 1.4% of vehicles in STATS19.
- Where the phase data were available, 12.2 % of the vehicles in OTS were found to be travelling above the speed limit.
- Inappropriate speed was recorded for 10.8% of the vehicles in OTS, compared with 2.9% of the vehicles in STATS19
- Excess speed was recorded as a contributory factor in 21% of fatal accidents, 11% of serious accidents, 6% of slight accidents and 7% of non-injury accidents. Excess speed was recorded in the OTS phase data for 58% of fatal accidents, 21% of serious accidents, 17% of slight accidents and 20% of non-injury accidents.
- For vehicles travelling at an inappropriate speed, only 61% were found to be below the speed limit, which again illustrates the under reporting of speed as a casual factor in STATS19.
The work also looked at the characteristics of speed related collisions and found:
- The majority of speed-related collisions involved some loss of control of the vehicle, usually on a bend.
- Collisions occurring on unclassified rural roads were over-represented in speed-related collisions.
- Excess speed was over-represented on 30 mph roads, and inappropriate speed was over-represented on 60 mph rural roads.
- Male drivers under the age of 30 were over-represented in speed-related collisions. This was particularly so for males aged under 21.
- Drivers/riders of cars and motorcycles were over-represented compared with drivers of other vehicles, as were drivers of older vehicles. Drivers of sports cars and hatchbacks were over-represented.
- Vehicles containing two or more occupants were over-represented
These findings reinenforce the negative effect of speeding on road casualties in Great Britain, and should encourage those who claim, by using published STATS19 data, that speed is not a main contributory factor in road collission to rethink their position.