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The image-based cargo inspection systems are generally intended to identify illegal practices. However, imaging processes from the scanning of motorized containers have been used for increasing industrial safety. This is made possible by the application of high-energy particle linear accelerators (linac). Measurements of both the environmental equivalent dose rate (δH*(10), and the integrated environmental equivalent dose (H*(10) were performed. The estimation of δH*(10) and H*(10) in the scanning channel, including the driver’s cab of the truck transporting the container, is critical. The aim of this study is to check the radiological safety for occasional users (drivers) by comparing the levels of δH*(10) and H*(10) with those adopted for public exposure. The study was experimentally conducted in a cargo and container inspection facility that uses a linac operating at the maximum energy of 4.5 MeV. During the in situmeasurements, a SpiR-ID identifier detector Model F 8929 MGP manufactured by Mirion Technologies was used. The measurements in the driver’s cab suggest that the procedure can be considered safe. However, a fast transient of δH*(10) was identified recording raised values (peaks) around 210× the threshold for public exposures in the first 9 s of each scanning procedure.

Within a radiotherapy room, in addition to the primary beam, there is also secondary radiation that leaks from the accelerator head and scattering caused by surrounding objects, the patient’s body and even the walls of the shielded room itself, designed to protect the external individuals, disregarding effects on the patient. The aim of this work is to study the radiation effect on the patient’s healthy tissues caused by scattering from a concrete shield expressed as equivalent and effective doses. MCNPX simulations of the linear accelerator Varian 2100/2300C/D were performed for a MAX phantom of a patient in a typical radiotherapy room. In addition, calculations were made with and without shielding. It was concluded that the concrete shielding affects in 5% the effective dose absorbed by the patient.

This study proposes a quick, easy, and low-cost method that can be used to assess the radiological safety of an irradiation line used for cargo and container inspection facilities. The radiation-emitting equipment used was a Smiths Heimam particle accelerator model HCVP4029 operating at 4.5 MeV. The radiation dose measurements were performed using a personal radiation monitor Ultra Radac mod MRAD 111 (Geiger–Muller). The ambient equivalent dose H*(10) was estimated for two facilities: A (real) (1.12E-03 mSv per scan) and B (fictitious) (3.25E-03 mSv per scan). The dimensionless factor R, which represents a ratio between two specific scanning (Ss) quantities regarding the facilities A and B, is introduced as a reference for assessing the level of radiological safety. This study compares facilities A and B by using a simple alternative safety assessment based on the R factor. The dimensionless R-value appears to be able to facilitate both the personnel’s and the general public’s perception of risk levels, even with no fixed scale.