The Tritium Laboratory Karlsruhe (TLK) is a facility of the Forschungszentrum Karlsruhe GmbH (FZK) where, under the European Fusion Technology Program, experiments are performed on tritium technology for the nuclear fuel cycle with a view to the needs of the ITER fusion reactor. The Laboratory comprises conventional infrastructure systems, tritium infrastructure systems, and experiments on a floor area of approx. 1200 m2. The licensed tritium quantity is at present 20 g; an application to increase this amount has been submitted to the corresponding authorities. The measures taken to safely handle such amounts of tritium are described in detail in this paper. Whereas the infrastructure is operated and controled from a central process control system (PLS), for the experiments local control systems (LLS) are used. Safety relevant signals are linked to a safety circuit. Some safety signals relevant to the operation of tritium systems are connected to the Central Emergency Control Center of the Research Center. Besides the operating, control and monitoring measures the safe operation of the Tritium Laboratory relies on highest quality standards, clear plant operation rules, a high degree of inherent safety and a number of tritium monitoring systems according to the latest state of the art.