Airport security became an important part of airport operations. A lot of information is required to be able to fuly assess the security situation at an airport. Often valuable information is not passed on to the security control center, but remains locally limited knowledge of the personnel at location. These pieces of information have to be delivered not only to the security control center, but also to the future airport operation center (APOC) in a useful way. Following the Level of Service parameter (LoS) that evaluates punctuality, etc. at an airport, the Level of Security indicator (LoSec) is being developed which allows the stakeholders at the APOC to capture the entire security situation at a glance. Since many security-related parameters cannot be quantified in an unambiguous way, fuzzy logic is used that makes calculations with imprecise measures possible and thus allows the computational evaluation of the threat level at an airport under consideration of the experience and knowledge of the security personnel.