The invention relates to a system for measuring the saturation level of a filter comprising a parallel filter; a divider for dividing said gas flow into at least a main flow and a sub flow, wherein said main flow is fed into said main filter and said sub flow is fed into said parallel filter, wherein the volume ratio between said main flow and said sub flow is substantially equal to the filter capacity ratio and/or filter volume ratio between said main filter and said parallel filter, and a detector operatively associated with the flow coming from the main filter and/or from the discharge side of said parallel filter, for measuring the concentration of the component in said flows and detecting a difference in said concentrations. The detector is arranged for detecting the concentration of the component at a temperature higher than 100.degree. C.