Biosafety levels
The classification of biological agents (BA) by risk group (RG) is not always related to the required biosafety level (BSL). For example, in the risk groups the techniques used are not always taken into account. Defining the BSL gives the final manipulator an idea of the containment needed to safely manipulate the microorganism concerned since, as well as each microorganism's inherent characteristics, the system needs the requirements regarding facilities and operational, technical and physical factors linked to the manipulation of a particular agent. Thus, four biosafety levels (BSL) are defined.