Doesn’t unduly slow boarding

The dwell-time spent at stops is a key determinant in the commercial speed that a service can attain, impacting both on the cost of production and the time-cost to the passenger. As such, it is important to minimize the time spent by passengers in boarding and alighting from vehicles.

One option is for fare validation to take place before boarding through controlling entry into a closed stop shelter, and this is widely used in bus rapid transit systems for example. However such a system introduces complexity where there is a graduated fare structure (in that a further control is required at the exit stop), and can involve a major infrastructure investment across the network if ongoing travel authority is provided within the original fare.

An alternative is for the ticket sale and / or fare validation to occur on the vehicle, but without the direct involvement of the driver. Tickets can be sold by a roving conductor after boarding, or by a static conductor (with an on-board queuing area to minimize vehicle delays). The former may result in some reduction in levels of revenue integrity depending on the zeal or motivation of the conductor, and the level of crowding in the vehicle. The latter is more secure, but the provision of the queuing area reduces maximum passenger capacity (and may make some seats relatively inaccessible and unattractive.

Tickets may also be sold by agents or vending machines at stops or shops prior to boarding, with subsequent fare validation taking place on the vehicle. Where this validation is mechanical (by punch or print), this process needs to be supported by periodic and random inspection control of passengers so as to ensure that the correct fare has been paid and then validated. However machine-readable fare validation only requires a cursory supervision by the driver on boarding, with a secondary validation on exit for any applicable fare rebate.