Berlin's airport operator still expects to open the capital's new Brandenburg hub in October 2013, but cautions that the target date could slip again after a review raised further concerns over the problematic fire-safety system.
The operating company, Flughafen Berlin Brandenburg, has detailed the main tasks required to complete the terminal's fire-protection system, which played a central role in the decision to postpone the planned opening in June.
Specialist engineering firm HHP Berlin, which advises the airport operator about the fire-protection system, has evaluated the situation as "more critical" than previously estimated, says Horst Amann, technical director of Flughafen Berlin Brandenburg.
While parts of the fire-protection installation are going to be modified, other sections will have to accepted as they are - even though they do not fulfil specifications under which the system was originally approved by the building regulator.
HHP highlighted the "discrepancies" between the system's concept, planning permission and actual installation in an October assessment.
The smoke-extraction system in the main pier needs to be modified. While the current installations extract smoke across different floors, the system should clear the individual levels separately.
This can be achieved in four areas of the main pier, but will not be possible in the central section. Amann says that further smoke tests need be conducted to demonstrate the existing system's reliability to the authorities.
Additional smoke barriers have to be installed in the baggage retrieval area, where conveyor belts link different floors.
In addition, the sprinkler system does not comply with the original approval. But it will not be modified, the airport operator says, owing to its complexity. The company adds that the system's reliability will need to be demonstrated in tests "as required by the regulator".
Further tests will also be necessary for the electronic door security system throughout the new airport. The operator states that it needs to demonstrate the system's reliability in case of power cuts.
Amann says that while the planned opening on 27 October 2013 "still stands" as a target, there is no guarantee that it can be met.