S 1.18 Intruder and fire detection devices

Initiation responsibility: Building Services Manager, IT Security Officer, Fire Safety Engineer

Implementation responsibility: Building Services

An alarm system consists of a number of local sensors that communicate with a central alarm unit, which then triggers an alarm when necessary. If an alarm system is already installed and can be expanded accordingly for a reasonable price, the core areas of the IT at a minimum (server rooms, data media archives, rooms containing technical infrastructure, and such like) should be monitored by the alarm system as well. This allows for early detection of fires, intrusions, and theft, for example, so that countermeasures can be initiated quickly. In order to guarantee this, the alarms must be forwarded to a location where someone is on duty at all times (i.e. to the gatekeeper, security guards, security service, fire department, etc.). It must also be ensured that this location is able to react appropriately to the alarm in terms of technology and personnel. In this connection, the alarm forwarding policies of the respective organisations and the requirements of DIN EN 50518 "Monitoring and alarm receiving centre" must be taken into account.

A concept for detecting and forwarding threats and triggering alarms should be drawn up for the different building areas. This concept must be adapted to changes regarding the usage. An alarm system is a complex overall system that needs to be planned and installed based on the type of building and risks involved. Therefore, planning, installation, and maintenance of an alarm system should be performed by experts. If such expertise is not available in the organisation, external support should be relied on. For example, there is a wide variety of different alarm systems that must be selected based on the corresponding security requirements and operating environment. Motion sensors, glass break sensors, door and window sensors, video cameras, and such like can be used to detect break-ins, for example.

The sensors and detectors can be networked in a variety of ways. Appropriate systems must be selected and installed depending on the type and size of the areas to be protected and the policies applying to these areas. When planning a new alarm system or when expanding an existing system, it should be ensured that the trays have enough capacity to handle the networked cables and that as few changes as possible are made to the existing cables in the tray.

Regular maintenance and functional tests (DIN VDE 0833 Parts 1-3 "Alarm systems for fire, intrusion, and hold-up") must be planned to maintain the protective effect of the alarm system.

If no alarm system is installed or the existing alarm system cannot be used, consideration can be given to using alarm detectors locally as a minimum solution. They operate completely independently and without any connection to a central system. An alarm is issued on-site or is sent to another location using a simple two-wire cable (possibly telephone cable).

An alarm system for detecting fires and intrusions must be installed for the operation of a computer centre. It may be useful to monitor other areas depending on the location of the site and its infrastructure.

Some rooms such as server rooms and data media archives have higher protection requirements. If no central alarm system is available, alarm detectors should be installed locally in such rooms. When using local alarm detectors for early detection, it must be ensured that an alarm can also be heard outside of the room in which it was triggered. The alarm signal can be transmitted over various routes and should be sent to a location that is manned around the clock. For example, there are solutions that can send an alarm to the employees' mobile phones wirelessly or via the telecommunications system.

Before planning an alarm system, a consistent protection concept for the corresponding building must be designed. When planning alarm systems for private and/or commercial buildings, it should be examined if the property insurance company will consider reducing the insurance premium, especially the premium for theft and burglary insurance.

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