[Medical aspects of stress measurement in the workplace]

To protect workers from overstress by occupational work, there are some methods to measure their working stress by recording different parameters continually during a period of several hours or days. The following physiological parameters are taken into consideration: heart rate, ECG, EMG, movement activities, breathing rate, oxygen consumption, body temperature, resistance of the skin and EEG. Periodically repeated measurements of the lactic acid in capillary blood as well of the catecholamines in the urine are also suitable. The heart rate is till now the most important parameter for practical use to estimate the physical and psychical strain. For values which can be registered by an electrical signal, three modern pickup systems are available: telemetry, magnetic tape recording, solid state memory. The most important advantage of the solid state memory used for the long time registration of bioelectrical signals (except those of high frequency) is actually evident. As the Laboratory of Occupational Medicine of the Federal Office for Industry and Labour is setting up a system to evaluate the individual psychical and physical stress, there has been developed a small memocardiometer which is able to record the heart rate during about 35 hours. The stored datas are transmitted via an interface to the computer HP-85, to be immediately available for calculations, tabulating and plotting.