Unexpected congestions are a common problem in the lives of urban citizens who need to travel to carry out their activities. This type of congestion causes unexpected delays to drivers and has traffic accidents and their duration as the main factor for their formation. In order to contribute to this problem, this study aimed to analyze the duration of traffic accidents on arterial roads of Fortaleza, Brazil, and their relationship with their causal factors. The duration of accidents was estimated based on traffic data obtained from electronic surveillance equipment, as the accident databases did not have this information. For this purpose, we generated profiles of speed and flow proportion per lane for days with accident and typical days to differentiate the impact on traffic caused by an accident from a typical traffic variability. The method detected the duration of 316 accidents with an average duration of 71 minutes and a standard deviation of 43 minutes. Next, a set of suggested hypotheses to explain the variability of accident duration was analyzed using survival models. The calibrated model showed that the severity of the accident, the traffic conditions at the accident location, the quantity and scheduling of the traffic agents, and the number of vehicles involved can have a significant impact on accident duration.