There is a rough correspondence between Risk Group (RG) and biosafety level (BL). Biosafety levels describe the set of safety practices and physical containment that are used to mitigate the risks of handling hazardous microbes.

• Biosafety Level 1 – RG1
• Biosafety Level 2 – RG2
• Bisoafety Level 3 – RG3
• Biosafety Level 4 – RG4

The risk group provides the starting point for determining the appropriate biosafety level. Depending on the nature of the experiment, precautions may be increased or decreased.

A summary of established biosafety levels with descriptions of agents typically used at that level will be discussed next.