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The minimum requirements for a good public transport system will include:

  • Reliable service with reserves in case of failure
  • Frequent service, less than 10 minutes waiting at any time throughout the working day,
  • Extended service, starting early in the morning and continuing until late at night
  • All vehicles with stepless boarding at all points on the system. Accessible for people with impaired mobility (including wheelchair users) without having to deploy special boarding equipment
  • Smooth riding characteristics without jolting, vibration or sudden changes of speed and direction

It would also be highly desirable to have some additional attributes which would enable the vehicles to operate inside buildings, so that passengers could wait indoors:

  • Emission free
  • Quiet in operation


These minimum standards could be achieved by means of a technologically advanced bus-based system or by an ordinary tramway - However, with buses there will be difficulties delivering the service reliably, day-after-day, over a period of many years.

The extra operating costs of a technologically advanced bus-based systems would not be met from the fare box and it would require a heavy subsidy. Furthermore, the short operating life of bus-type vehicles and their toll on existing road surfaces would impose a continual drain on resources in order to prevent deterioration of the equipment and infrastructure after a relatively short period of operation.


However, the requirements set out above are regarded as normal conditions for a tram network



The high fixed costs of a tramway, combined with relatively low operating and maintenance costs, automatically give a number of advantages.

a) Permanence - Trams and tramways typically are designed for lives of 50 years or more. Many personal lifestyle decisions are influenced by the availability of permanent transport links and a certain level of trust in public transport is necessary before changes in travel habits can be made. The perception of bus routes as transient facilities, subject to withdrawal or change with little notice, is not conducive to that trust - whereas the permanence of tram routes is a very positive influential factor.

b) Service frequency - The economical way to operate a service with high fixed costs and low running costs is to wring as much utility as possible out of the expensive equipment. In the case of a tramway, this means that a large number of vehicles can be economically deployed in service at most times of day, giving a frequent service.

c) Operating hours - The low operating cost also means that the point at which passenger numbers are no longer high enough to justify operation of a service will occur much later in the evening. When operation is continued into the late evening, this in turn means that more passengers will travel by public transport earlier in the evening because they are assured of being able to get home again. By the same reasoning, early morning operation is also a feature of tramways.



During the construction of a tramway, various ductwork must be laid down beside the track to take supply and control cables to remote parts of the system. Spare duct space then allows the incorporation of enhanced communication facilities at minimal extra cost; making such features as Closed Circuit Television Cameras, Vehicle Tracking and Passenger Information Displays a normal part of every modern tramway. With a bus-based system, these become expensive extras which are often omitted

In public transport, some degree of waiting is unavoidable but these standard facilities on tramways allow the stress of the experience to be reduced to the lowest possible level. The vehicles' positions are known to a central control facility, which allows reliable predictions of the arrival time of the next vehicle to be communicated to the passenger. The CCTV gives confidence to the intending passenger that they are waiting in a safe area.

The tram rails form a smooth surface for the tram to run on. The track is much less prone to wear than a road surface subjected to a similar loading from a bus route. The riding characteristics are not at the mercy of road surface conditions.

Because tramway operators are aware, at the outset, of the porential for disruption cause by a broken-down vehicle on the tracks (either a tram or another road vehicle), they have to have contingency plans in place at all times. A damaged or unserviceable tram is immediately removed and replace with a spare - and the service continues uninterrupted.



On board the vehicles, many modern tramway systems still use conductors. This is not a hangover from the past, but is made economically possible by the extra revenue-earning capability of a tram compared with a bus. With a conductor to help passengers board and alight and to relieve the driver of fare collection and ticket checking (which would delay the service), the tram is capable of giving a much better service than a comparably-sized bus.

The presence of a conductor does much to engender confidence and safety, particularly for elderly persons, who may have impaired mobility or may feel unsure of their destinations and the conventions of public transport. On late night and early morning services, the presence of a conductor is an important factor for the security of passengers who might otherwise feel vulnerable travelling on public transport during these hours.



The noise and emissions of buses can be reduced below the levels we currently experience, but they cannot be prevented completely. Trams produce no emissions and little noise, which allows them to opearate inside buildings. This is particularly important for areas such as hospitals, where elderly and frail patients and visitors are able to wait for their transport indoors.

At a major interchange or an important building, a completely enclosed indoors waiting area gives great prestige as well as convenience and comfort.

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