[en] Introduction: A shielding design suitable for rooms with accelerators is an important security measure for the protection of IOEs and members of the general public. NCRP 151 lays out the general considerations for the calculation of shielding in standard radiotherapy rooms, although it is noted that many shield designs differ from this standard room, such as mazeless rooms. Labyrinth-free rooms have been more commonly used, as they require less space to be built. As they are recent constructions there is no international norm or recommendation for those type of rooms. Therefore, the objective of this study is to evaluate the absorbed dose relative to neutrons in a room model without labyrinth, and to verify if these doses are within the limits established by CNEN. Methods: To evaluate the absorbed doses due to neutrons, we used the computer simulation with the code MCNPX. Accelerators were simulated with energies of 10 MeV, 15 MeV and 18 MeV. Results and Discussion: To date the results have been obtained for accelerators of 10 MeV. The results were compared with analytical calculations. The equivalent dose obtained for neutrons is within the permitted limit, according to the CNEN regulation. The results for the other bundles are still being calculated. Conclusions: This study shows the equivalent doses due to neutrons in non-labyrinthine, non-labyrinth radiotherapy rooms established in NCRP 151. This study is necessary to establish guidelines for the construction of this type of room, so that the individual dose limits of IOEs and the public are respected