Reliability and safety of BOS and BESThe BOS ensures reliability and safety:
If the barrier fails to close or to do so on time this can have disastrous consequences for the hinterland. Exceptional reliability is therefore the most important demand made of the system. In order to ensure such reliability the BOS hardware contains two redundant branches. The script interpreter explores its way and starts with the first branch. If an error arises in that branch, the computer switches to the second hardware branch, which is identical to the first. If an error later arises in the second branch, the computer then continues with the sound element of the former branch. This is a continuous process: at any one point in the course of a procedure the BOS can - if necessary - decide to switch between the two branches. This makes BOS highly reliable.
No human beings are needed for closing the barrier. Although if the BOS is considering closure, it will then nevertheless notify the operation leaders and breakdown teams at least eight hours beforehand.