The A1 and A2 values of the Q System described in the advisory material SSG-26 have been developed to provide maximum allowable contents in packages not designed to withstand ac-cidents. Current values were determined in 1996 according to specific scenarios for five expo-sure pathways. Since then, the ICRP has published revised radiological data. In September 2013, an international working group was created to discuss the improvement of calculation methods described in the Q System. Within this framework, it has been decided to change the current deterministic and empiric method to a more accurate one, based on Monte-Carlo calculations. This evolution allows the working group to be more flexible and to get more accurate results, for instance by taking into account all particles created. It is an important evolution as QA and QB, used to evaluate the effects of external exposure (in order to determine the A1 values), are only related to, respectively, effective dose due to pho-tons and skin equivalent dose due to electrons. The same issue exists for QD (contamination due to beta emissions only) and QE (exposure due to submersion in a noble gas). The evolution now allows to account for all radiations for all Q values. Of about a thousand radionuclides to be considered, the working group retained 6 well-known radionuclides (60Co, 154Eu, 134Cs, 192Ir, 85Kr, 18F) to firstly evaluate the consequences of this evolution on the QA and QB values. This list of 6 radionuclides was agreed because it con-tains different type of emitter (-) and covers a wide variety of use. Therefore, IRSN has analysed, for the working group, the contribution of each radiation (, Auger & internal conversion electrons, -) on the effective dose and on the skin equivalent dose to show the impact on the A1 values. The possible consequences on the transport of radioactive materials will also be discussed. The new Q System would, once validated by the TRANSCC, be able to provide A1 and A2 values based on exposure from all radiations to all sensible organs and to the whole body and for at least two irradiation field.