Description: The statistics of emergency situations are considered. A clear global trend of increasing economic damage and the number of deaths in man-made and natural disasters is revealed. It was suggested that both the risk of using chemical weapons in the course of combat operations and the high probability of the emergence of a hotbed of chemical contamination on the territory of Ukraine as a result of accidents at potentially hazardous facilities are decreasing. The state of chemical safety and the population provision with personal protective equipment (PPE) is analysed. A technique for determining the design efficiency of filtering PPE is proposed. Variable parameters of PPE have the following design characteristics: maximal inhalation toxic dose, absorbed PPE, coefficient of sucking into the respiration zone; coefficient of suction in the zone of vision; specified by the technical specification, the protective action time of PPE. The fixed PPE parameters specified by the technical specification assume the following: the value of the threshold inhalation toxic dose, the value of the threshold concentration of poisoning substance (PS) when exposed through respiratory organs, the value of the threshold concentration of PS when exposed through the eyes. The effectiveness of a single PPE is defined as the probability of fulfilling its functional purpose, taking into account all possible ways of penetration of PS into the human body. This value is proposed to be defined as the product of the probability of performing protective functions by the filtering device (box), the probability of performing protective functions, taking into account the sucking into the breathing zone, the likelihood of performing protective functions of PPE, taking into account the suction in the zone of vision. To determine the effect of small changes in variable parameters on the effectiveness of PPE, the elasticity of each of the factors with respect to variable parameters is determined. The factors absolute errors are calculated depending on the variable parameters absolute error. For the final evaluation of the effectiveness of PPE, taking into account the variable parameters absolute errors, interval arithmetic with the representation of numbers in the centre-radius system is used.
Keywords: consequences of emergency situations, chemical conditions, filtering personal protection equipment, the effectiveness of personal protective equipment, the elasticity of the function, the absolute function error, interval calculations, the centre-radius system