Features of electromagnetic and noise environment in the workplace of the staff of MRI departments: problems of hygienic regulation and control

Abstract

Introduction. Magnetic resonance imaging (MRI) is one of the most dynamically developing, high-tech diagnostic methods. At the same time, the specific features of the electromagnetic environment and noise exposures at the medical and technical personnel operating and maintaining MRI workplaces are not well understood and are currently not taken into account when conducting a hygienic assessment of working condition in the Russian Federation. The aim of study is scientific substantiation of the need to improve the hygienic assessment of electromagnetic and noise conditions in the workplace of the staff of MRI departments. Materials and methods. An analytical method to evaluate the current domestic and foreign regulatory and methodological documents that determine the hygienic assessment requirements for electromagnetic environment and noise in MRI departments was used. More than 4 thousand measurements of the intensity of electromagnetic fields and noise in 88 rooms in Moscow equipped with different types of MRI (from 0,1 mT to 3 T) and studies of the performing duration various types of work and electromagnetic field and noise exposure on personnel was done. The amplitude-time and frequency parameters of the variables of the electromagnetic field (EMF) and sound pressure detailed studies have been carried out. Results. Significant differences in controlled indicators, acceptable exposure levels, and control methods has revealed by critical analysis of domestic and foreign hygienic regulatory and methodological documents. The studies showed that the medical and technical personnel of MRI departments are exposed with high spatial and temporal gradients static magnetic fields and extreme levels of noise during diagnostic work in the immediate vicinity of the tomograph magnet. The presence of time-varying magnetic fields in a wide range of low frequencies and radio frequencies having a complicated (pulsed) waveform is a feature of the electromagnetic environment in MRI. New standardized control parameters and limit levels for low-frequency ranges magnetic fields for their adequate hygienic assessment are proposed. Conclusion. The studies made it possible to substantiate the proposals the improving of electromagnetic field and noise hygienic assessment at the MRI staff workplaces.