The European Commission is currently discussing the importance of introducing new limit values for the exposure of employees and a limit value for welding fumes. What is being examined here is whether a general limit value for welding fumes in the Directive on Carcinogenic, Mutagenic, and Reproductively Toxic Substances (CMRD) 2004/37/EC is included in Annex I of the CMRD list. However, there are already difficulties in complying with existing limit values. The WELDOX project by DGUV still includes accurate information about welding fume concentration levels. That means concentrations in the workplace are often in the limit range of the AGW (1.25 mg/m³), but the AGW for manganese (0.02 mg/m³) is often significantly exceeded. Our measurements also confirmed this in metal companies in Saxony. What makes matters worse is that there is no test procedure to determine the separation effect of industrial vacuum cleaners for manganese. However, VDI 2262 requires this to allow clean air to return. Specifically, the clean air concentration must be a factor of 0.2 (4 mg Mn/m³) below the AGW. A verification procedure for testing welding fume separators is currently being developed at ILK Dresden.