Safety systems (AL3) and systems relevant to Safety

The AL3 systems are basic life protection and are especially important during the shutdown; there should be no point in the LHC underground areas in which a person is not or cannot be informed of the dangers around him when they exist and so take appropriate action. The implantation of the different detection and alarm systems will be reviewed and their performance and reliability examined. The need for fire doors to control released Helium will also be considered, which may have consequences for the ventilation and access systems.