Protection of personnel and patients in diagnosis and therapy with ionizing and non-ionizing radiation

Abstract

Most of the sources used in physiotherapy use pulse magnetic fields; spark-discharges; radiofrequencies (RF); direct and low-frequency electric currents, electrical pulses; ultraviolet (UV) and infrared (IR) radiation; broad-spectrum lamps; lasers. The most relevant diagnostic sources are MRI scanners emitting static magnetic field, low-frequency fields, RF. The exposure of medical personnel to NIR depends on the type of transmitter, irradiation power, mode of operation, specific application, access of medical personnel to the treatment zone, shielding of the source and workplace, time duration of exposure. Devices for electric current therapy like pulses, ionophoresis therapy, vacuum therapy, emit magnetic field less than several μT. The devices for subthermal therapy emit RF energy up to 9,8\u202fW/kg, compared to 0,4\u202fW/kg basic restriction for whole body exposure. The average daily dose of the staff at 10 patients per day is 18,356\u202f(V/m)2·h. The dose of medical personnel in protective chambers averaged per patient is WE\u202f=\u202f23,88\u202f(V/m)2·h. Regard to MRI equipment, the basic restrictions for static magnetic field for normal operating conditions exceed the action values for people at specific risk, also for risk of attracting ferromagnetic materials. In the case of the use of optical sources, power densities exceed the exposure limit values, and therefore the permissible stay is limited to minutes and seconds, and in some cases it is inadmissible. In cosmetic centers, sanatoriums and SPA centres, power densities are significant and some of them are not controlled (tanning beds and IPL systems). The laser systems applied in physiotherapy are mainly class 3R (visible range), which only pose a risk to the eyes, in some cases 1C. For some procedures, lasers of class 3B are also used which cause risk to the eye by intra-beam viewing as well as diffuse reflected radiation. In cosmetic centers where specific lamps and high class (4) lasers are used, there is a risk for serious skin burns and eye damage.