| In the last decades, electronic irradiation accelerator has made great progress and been widely used in food preservation, material modification, medical equipment disinfection, etc. Because of its distinguishing feature of reliability and safety, electronic irradiation accelerator has attracted more and more attention of the investors, and created a huge economic value and social benefits. In the near future, it will become the mainstream equipment of irradiation processing industry. So the further study of the shielding design around irradiation accelerator is of great significance.Based on the relevant NCRP reports, this paper summarized the estimation method about the low-energy accelerator's radiation field comprehensively, and specifically measured the radiation fields around two electron linear accelerators. The measurements results are consistent with that of our calculations, which proves the calculation method used in estimation is reasonable. The measurement results along the maze show that the maze must be long enough in order to achieve the desired shielding effectiveness.Using the Monte Carlo procedure MCNP,some questions met in the process of shielding estimation are studied. Our research mainly focus on such problems as the X-ray emissivity from the electron beam bombarding the iron target, the reflection coefficients of photons in concrete media and the determination of the scattering areas in the maze's bend. Simulated results coincide very well with the data recommended by some references, indicating the rationality of our process of relevant parameters. Further more, comparing with some references, these simulated results give more comprehensive data.Finally, the problems about pipeline penetration in shieldings are calculated and the effection on the shielding ability by the ducts are given quantitative in the paper. In the future, our investigation will provide a significant reference for shielding design.
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