Recent years have seen increased efforts to improve the punctuality of trains. One of the reasons for this is that punctuality is a key performance indicator concerning passenger satisfaction and punctuality can thus be seen as important to both retain current passengers as well as to attract new users. Punctuality is closely related to delays, indeed when a train is not delayed it will most likely be punctual. Trains can suffer from a delay for various reasons and one type of delays are the so-called dwell time delays. Dwell time delays arise when a train is stationary at a station for longer than scheduled. The thesis presented here focuses on why dwell time delays occur, the impact of passengers on dwell times, how dwell time delays can be measured, and finally how the risk of dwell time delays can be reduced.
Several years of passenger counts collected on board trains in Stockholm and the region of Skåne in Southern Sweden were used to study and analyse the impact of passengers on dwell times. The results of these analyses indicate that, although the volume of passengers is often seen as
the main cause of dwell time delays, this is not necessarily the case. Instead, the findings from the studies show that the volume of passengers acts as an accelerator for other aspects such as an uneven spread of passengers or passengers queuing up in front of doors. A high volume of passengers on its own is not sufficient to increase the risk of dwell time delays, but this will happen when there is a high volume of boarding passengers that are unevenly spread between the doors.