Safety, comfort and security

Here we attempt to define general and technological independent criteria for safety, comfort and security.

Safety and comfort

In order to define criteria we need to separate between between two modes of operation:

• nominal operation
• emergency operation

It is assumed that passengers are seated, facing the front, without safety belt.

nominal operation

In nominal operation we adopt the comfort criteria from E. Anderson [6]:

• acceleration at maximum g ($g=9.81$m/s) for a duration of maximum $1$min

• jerk^1.1 at maximum $0.2$g/s
• no oscillations between 3 and 10Hz

For the transport of passengers apply the additional criteria:

• temperature adjustable between $288^\circ$K to $300^\circ$K ($=14.84^\circ$C to $26.84^\circ$C)

• air pressure at $1.01325\pm 0.101325$hPa ($=1\pm0.1$atm)
• fresh and clean air, with oxygen contents of above $10$% (ventilation, smoke-, particle-, or CO$_2$ filters)

In the event of a longer unplanned system shut-down (power failure, blockage due to vehicle breakdown, e.t.c) there should be provision for rescuing passengers or to get passengers to the next stop or an emergency alighting point within $1$hour.

emergency operation

If the system is in emergency operation mode then safety criteria apply. As a general rule:

serious injuries, directly or indirectly caused by the system, should be physically impossible.

In particular:

• maximum deceleration of $0.5$g for seated passenger without safety belt

• temperatures, smoke, and gas should not threaten health or life in the cabin and on escape routes

External damage (vandalism and unauthorized deviation of vehicles, sabotage or natural catastrophes) should be reduced but can be never completely eliminated.

Security and psychology

Security and psychological issues are important, in particular for automated TS because:

• there is nobody near, who can immediately help in case of danger. People may be afraid to use the system by their own

• criminal hackers or terrorists may try to sabotage control and information systems
• some people might get claustrophobic or depressed if vehicles feel too confined

Therefore, the following general design rules apply in order to improve system security:

• assistance and information systems: the user must be able to call for assistance at any time, possibly using the information systems that are accessible at stops and inside vehicles

• passive protection of vehicles and infrastructure: vehicles and infrastructure should be sufficiently protected against certain violent attacks such as blocking of vehicles by throwing objects on the track, breaking into vehicles, etc

• camera supervision: critical locations like stops or areas where vehicles move slowly should have camera supervision or be periodically visited by vehicles that are equipped with cameras

• isolated information systems: the system information networks which transmit vital data should be isolated from public networks. Access to internal information should only be possible with a sufficient authentification and only at authorized (physical) locations

• computer networks and other centralized information systems should not be safety-critical
• sensors: the system should be able to detect damage and inform security staff. There should further be sensors that detect unauthorized intrusion into the internal information system

• friendly interior vehicle design: the inner vehicle shapes and colors should give a feeling of security and space Bright colors should be preferred to dark colors.