A Relationship between Accident Types and Causes

A study was done on a road in the Western Cape of South Africa, the R44, to investigate the causes of road accidents. The causes of the accidents on this 25km stretch of road were deduced from analysing 404 accident reports and from relationships that were determined with other factors. Risk factors (human-, vehicleand environment factors) are proposed for the 14 accident types that occurred on the R44. The risk factors were determined from the analysis of the accident reports, relationships found and literature studied. When the risk factor percentages are weighted with the number of times the accident type occurred, the human factor is the biggest factor (75.4%), followed by environment factors (14.5%) and vehicle factors (10.2%). The main human factors were negligence, excess speed, dangerous overtaking, pedestrians in road and inconsiderate driving behaviour. The vehicle factors were mostly faulty brakes and tyres. The main environment factors were daylight, rush hour traffic and inadequate facilities for pedestrians. These risk factors are in the range that the South African Department of Transport issued, which implies that the risk factors per accident type can be used as a starting point to determine the causes of road accidents.