Safety & security
Passenger safety and crime prevention
The safety of passengers has always been of paramount importance to the designers of Metropolitana Milanese. The rarity of accidents of any kind on all three lines of the Milan metro is clear testimony of their continuous efforts over the years which are still at the heart of their concerns. To guarantee safety in a transport system, it is necessary both to minimize the risk of accidents (safety) and to prevent criminal behaviour, such as vandalism, pickpocketing, violent acts and crime in general (security).
Safety
To guarantee the safety of passengers and workers, various equipment systems have been adopted and, over time, constantly developed:
- the design and construction of the tracks is always carried out with the primary objective of minimising the risk of derailment. As an example, one special safety device in potentially the most critical situations (on tight bends or in zones adjacent to certain structural components) is the installation of a safety rail to contain the effects of derailment;
- signalling systems to guarantee safe operation even in the event of human error, through automatic and constant detection of the position and speed of each train.
The system provides for: automatic braking of the train if it gets too close to the train in front, preventing collision; management of points, preventing routing which is incompatible with them; train speed control, taking into account track conditions and traffic on the route section; automatic braking in the event of passing a red signal, due to human error for example; control of the door opening side at stops.
All the functions are carried out within an intrinsically safe system: this means that any possible malfunction of the system cannot compromise the basic functions. The system reacts to faults with pre-arranged safety procedures such as slowing down or stopping trains on the track in question.
- the systems providing power to the trains and stations, which ensure a high level of energy availability by virtue of several levels of redundancy, greatly reducing the likelihood of black-outs in stations or trains stopping in mid-journey.
- the telecommunication and central control systems allowing the operations room to remotely manage the whole metro line, in relation both to normal operation and the provision of rapid response in the event of an emergency.
- the fire prevention and management systems which reduce the risk of fire and allow its effects to be quickly contained.
Security
From the security point of view, on the new lines and the most recent extensions, measures have been adopted to prevent and if necessary manage situations following criminal acts.
- A closed circuit TV system (CCTV) monitors all the important areas: platforms, entrances to tunnels, atriums, corridors, interior of lifts, escalators, station operators’ cabins, automatic ticket dispensers. The images are sent to the national police control rooms. Many of the cameras are set up for 24 hr recording.
- A station videophone system allows members of the public to make immediate contact with the control room.
- A public address system provides audio information messages to passengers, which may give warnings (e.g. drawing attention to pickpockets) or advise action to be taken in the event of emergencies.
- An intruder alarm system monitors secondary entrances to tunnels and stations such as emergency exits, ventilation rooms, grilles, equipment lifting/lowering shafts and, at night, the main entrances.
- Radio systems also allow communications, even underground, with staff, national police patrols and the fire brigade.
Over the last few years, Metropolitana Milanese has undertaken a series of projects, some international, designed to prevent and manage underground fires in railway, metro and road environments. In particular, the projects dedicated to metro systems are being developed in terms of prevention and protection..
equipment and systems for detecting smoke and heat in order to promptly alert the operations room and then the rescuers;
The first requirement for prevention is the use of low flammability materials, which do not emit toxic gases or thick smoke. The element of protection refers to the presence and activation of:
- equipment and systems for detecting smoke and heat in order to promptly alert the operations room and then the rescuers;
- fire hydrants in the station and tunnels;
- extinguishers in all stations;
- automatic sprinkler systems at the train platform stop area, in sidings, on escalators, in shopping areas;
- water curtain smoke barrier systems, to contain the spread of combustion products from the platform level to the upper levels;
- a station ventilation system, to remove smoke from a fire on a train which is stopping and at the same time bring fresh air to passengers moving towards the surface;
- a tunnel ventilation system to remove smoke in one direction from a possible - though unlikely - fire in a train stopped half-way along the section of track, the opposite direction being kept free to allow a viable escape route under conditions of safety and at the same time facilitate intervention by rescuers;
- exits along the tunnel, allowing people to escape to the surface via routes other than those usually offered by the presence of the two nearest stations;
- points of access for the fire brigade throughout the tunnel, to offer multiple possibilities for intervention in any kind of emergency;
- tunnel public address system, to give information to passengers during the evacuation of a train stopped along the track section;
- emergency tunnel lighting, with lighting levels exceeding those for normal operation.