Assessment of hazard caused by intrinsically safe systems

Measures for evaluating the degree of safety when intrinsically safe systems are applied in explosive atmospheres are presented. A number of advantages and some disadvantages of the proposed measures are shown. The major advantage of the proposed measures is approaching the real operating conditions of intrinsically safe systems. The obstacles on the way to applying the measures are the difficulties of obtaining sufficient statistical data concerning: the reliability of the devices, the explosions (fires) and their causes as well as the diversity of the processes of arising gas hazards. These obstacles should not, however, disturb the studies of the problem and in particular gathering the necessary experimental data from industry