In this work, we explore the possibility of fixing the number of new non-sequential chiral-type generations of fermions that could be added to the Standard Model by combining the condition that arise from the anomaly cancellation with the restriction in the number of flavors imposed by the QCD asymptotic freedom. We found that the maximum number of new generations is four, and this allows us, at the same time, to place limits for the electrical charges of quarks and leptons within an SM-like framework. Our result is compatible with the constraints involving new generations and their contributions to the oblique parameters S and T.