Microwave diathermy in physiotherapy units: a survey on spatial and time heterogeneity of the electromagnetic field.

Microwave diathermy (MWD) is a therapeutic system that has been in use for some decades now in all physiotherapy settings, following the regulations of national facility establishments. The validity of diathermy devices is probably reduced as their working time increases, introducing the need for the device to be controlled/reset by qualified personnel in order to maintain its effectiveness in sessions and to accurately deliver the energy output that the physiotherapist asks for. However, while MWD has been a vital tool for practising physiotherapists, there is no clear evidence of a health burden due to incorrect usability. Additionally, due to the fact that physiotherapy rooms contain physiotherapeutic equipment it is observed that during the use of the diathermy device there is spatial heterogeneity in the interior space. In this work, the results are presented of the first national survey for quality control of MWD systems installed in physiotherapy rooms existing in urban and rural areas in Greece. Serious concerns about the technical status of the equipment as well as staff and patient safety, regarding the levels of non-ionising radiation emitted from MWD devices, are discussed. Additional evaluation is included of measurements in empty physiotherapy rooms while the MWD unit is transmitting at three different input powers (50 W/100 W/150 W-these are the therapeutic protocols used most frequently by physiotherapists) and in fully equipped physiotherapy rooms. Field strengths measured around MWDs normally working at different angles, distances and times compared to international limits revealed great spatial and time heterogeneity, raising serious concerns about the safety of occupational workers or other patients.