The bigger picture

With acts of terrorism and an increase in the number of robberies with violence ever more prominent in the public eye, it is clear that the security installer is facing times of change and new challenges.

Unfortunately it is difficult to prevent or legis-late for inhuman acts of this type and magnitude. Therefore the technological advances and systems for the future must be directed at reducing risks and capturing 'events' in an effort to systematically control the problems.

With regard to terrorism, security is now playing a more significant role in all areas where people are gathered together in large numbers and in clearly defined locations. This is where the vulnerability of the public is most apparent.

A classic example is the underground tube network, and I personally have some experience of the security systems currently employed in these areas. If we overview the technologies in use we can refresh our minds on those concepts and give some thought on how we may make contingency plans for new schemes.

The underground is a good example of how we can employ a variety of the systems available. However we can never put into practice security systems or procedures that remove in total the risks of terrorism or destruction on the underground. We are only able, at best, to control the risk. To introduce measures which negated the risks would make the whole network unmanageable and no longer able to function as a commercial service.

Cameras at all entry/exit points
On the underground, we must employ CCTV cameras at all of the strategic positions and any sensitive areas in order to record the movement of all personnel. The entry/exit points of the stations are important, so that the image of every person who has entered the station is captured for time and date. Camera defaulting is installed so that a pan/tilt/zoom unit may be immediately taken to a pre-set default position in the event that an unusual activity has occurred at a sensitive area.

Such activities can be the result of an access control violation if an unauthorised transaction is made at a reader, or entry to a point is made without a system being first unset. This can be in response to an output from any standard intruder alarm system detector or from a perimeter detection device such as an active infrared beam, either of which may be monitoring areas that would not normally be accessible to the public.

Security installers will be presented with enormous challenges – but no easy solutions

For instance, active infrared beams may be used to monitor the movement of trains but be so arranged as to respond in alarm to a person entering the lines at a given point. The beam settings can be set in order to differentiate between a human and a train, as the human can only disrupt the beams at the lower elevations. An option is to time-set the beams to account for the greater timespan of a train passing a given section of track. For all events a buzzer at the monitoring station must sound until reset.

With all alarm conditions of this nature it is important that a reset operation by a system user is incorporated and that this is accountable.

Observing as it happens
Although there is a need to record images, there is an additional requirement to observe current events, so pictures are generally sent by fast scan over an ISDN line for viewing at various points and at a central depot that is remote from the area being protected.

This may also include the monitoring of a depot, station or maintenance repair area that is occupied at all times or may be closed outside of normal working hours. There must also be adequate lighting to support the cameras and access control for vehicles that must enter the depots. In practice therefore, the underground will use an accumulation of all of the traditional technologies with which we are familiar but these will be integrated in such a way that they complement each other. There must also be a facility to manage and maintain each and every system individually. By separating the maintenance and servicing of the different systems it allows any technique to be easily amended or temporarily disconnected without influencing the others.

Vast number of camera inputs
As installers, we are all familiar with the role of multiplexer and VCR alongside the video sequential switcher which will switch from one camera signal to another in order to view all of the cameras on a system over a period of time. However the systems that use multiple cameras can only operate with a video matrix switcher. This is an alternative to the sequential switcher so that a number of operators can concurrently view and control the system. Operators can even be allocated priorities. The matrix accepts a vast number of video inputs from the cameras and also accommodates more outputs. For instance, a particular camera input can be switched to a desired output so that it can be viewed on the most appropriate monitor. The matrix will also have pan/tilt and zoom keyboards mounted at a number of convenient locations in order for the system user to drive the camera head, zoom lens and normally also the wash and wipe facility. Equally the matrix will generate the camera identification, time and date, alarm messages, operator using the system and any other related on screen information that is to be superimposed onto the video signal.

Fitting into the matrix
Using a PC-based graphical user interface with touch-sensitive screens, the system becomes compatible with many other site and management operating networks normally running software designed to work in Windows. The intelligence of the matrix even enables other systems to be controlled so that, for instance, lighting can be energised in response to an activity or high security doors may be electrically locked. The matrix can be so arranged to carry out a host of functions to collect signals from other management systems. These can be as simple or as complex as any site demands.

The tube system illustrates that the installer carrying out a survey must look at an ever-widening picture …

In practice we can see the underground security systems being essentially made up from intruder panels protecting the depots, control areas and all of the main transmission and monitoring equipment. Allied to these is the access control equipment that is used to log personnel through sensitive areas not intended to be used by the public. Beam detection equipment or an equivalent technique may be used for perimeter sensing to ensure the public cannot gain access to lines or pass the access control boundaries. The CCTV network must be comprehensive enough to ensure that all users of the underground are monitored and recorded. Many cameras must be programmed to default to prescribed positions if an alarm input is generated at one of the other security systems. The equipment needed to retain the images must of itself be held in a highly secure position.

Seeing the wider picture
Using the underground system as a benchmark it illustrates that the security installer, when carrying out a survey, must now become further committed to look at an ever-widening picture. We must protect sensitive areas by means of the standard techniques with which we are familiar yet we must also consider the protection of other management systems. To overlook these would be dire.

Emergency lighting is always an issue but what if we fail to use our knowledge to look after something as strategically important as the Customer Information System (CIS)? The CIS provides the control and monitoring facilities for all of the passenger information displays and public address systems. In fact these are complex communication networks which, if destroyed, would create enormous difficulties in alerting personnel of the need to evacuate an area.

This system needs protection by the traditional techniques available to us since it is the only means of allowing the user of the network to monitor the train movements, maximise the information, display the data and to give appropriate announcements through the loudspeakers.

Although the tube stations present enormous levels of risk to the public the electronic security systems that are installed within them can only be based on those available for any risk. In the underground networks only the highest quality goods are employed and that the control equipment is powerful and intelligent.

Protecting the systems It remains to be said that we are still unable to cater for every extreme threat. It is only by installing at the highest levels that we can deter and subseq-uently control, to some extent, an element of the new threats with which we are being faced.