For security reasons, each hazard alarm system (HAS) integrated via OIS must have at least one permanently active transmission device to an emergency service or have an operating device in case of malfunctions in the hardware, software, or transmission equipment used.

The control unit of the HAS is either permanently active or switches automatically from standby mode to active operation in the case of a malfunction as mentioned above.

A VdS-compliant integration of OIS with hazard alarm systems is not possible.

It should be noted that the technically plausible integration of message and information systems with hazard alarm systems using OIS requires compulsory VdS approval as things stand. It is vital that the customer be informed of this in writing in a clear way. If a customer disregards VdS approval for his/her HAS, then it should be noted when integrating the message and information system (for example TOPSIS) via OIS that:

  • the HAS is or remains always capable of operating and displaying self-sufficiently;
  • functionally, a nonreactive connection is safeguarded even in the event of a failure in the Manager;
  • the devices used for the message and information system (due to their constructional characteristics, normally outside the requirements of standards and guidelines for hazard alarm systems) at least meet high quality standards and are used in a system exclusively for the HAS.

Public Interface (PI) makes possible the development and usage of system-specific Cu-Handlers for OIS. A Cu-Handler constitutes the software link between a subsystem, for example a hazard alarm system, also called a "control unit", or in short, "cu", and a message and information system (for example TOPSIS as part of the Siveillance Control product family). General application functions for integrating “cus” to the message and information system are provided using OIS.

Such an integration is currently not released for the expansion of VdS- compliant systems.