Substantiation of the influence of meteorological and topographical conditions on the spread of a cloud of polluted air

Abstract

Objective. To substantiate the significant influence of meteorological conditions and terrain (topographic conditions) on the behaviour of hazardous chemicals (HCS) in the atmosphere (environment) in the event of an accident at a chemical hazardous facility (CHF) with its release (discharge), taking into account that these conditions can change in space and time. Methods. The general and special methods of theoretical and computational research methods, regulatory and legal documents on labour protection were used. Conclusions. Changes in meteorological conditions (degree of vertical stability and wind speed, downwind temperature) also change the speed of the contaminated air cloud front. This, in turn, changes the depth of the air mass transfer and, accordingly, changes the extent of the actual chemical contamination zone. The main variables that determine the formation of the level of atmospheric pollution include the direction of transfer of the cloud of HCHs, the speed of their transfer, atmospheric stability and the degree of vertical mixing of harmful impurities associated with it, the thermal state of the air mass, which determines the initial rise of emissions, the leaching of HCHs by precipitation, their accumulation in fogs, and the inertial factor. A chemical pollution zone is an area where hazardous chemicals are present in concentrations that are dangerous for humans and other living organisms in the area. This factor should be taken into account when making decisions on rescue operations, as each component part of the contaminated area will have different concentrations of HCS. When choosing measures and methods of protection of the population, it is necessary to take into account not only the physicochemical and toxic properties of CWA, the scale of contamination, but also meteorological conditions and the nature of the area where emergency rescue operations will be carried out. Scientific novelty. A method for predicting the impact of meteorological conditions and terrain characteristics in the event of an emergency situation with hazardous chemicals in the surface layer of the atmosphere is proposed. Additions to regulatory and legal documents on civil protection are proposed. Practical value. The developed recommendations will facilitate the consideration of meteorological conditions and terrain when predicting the extent of the spread of a cloud of contaminated air in the event of a CBR accident and the legal regulation of civil protection in accordance with the current norms of legislation in the field of civil security