FORMATION OF MATHEMATICAL APPARATUS OF METHODS OF FIRE AND EXPLOSION SAFETY CONTROL OF LANDFILL

The authors analyze the fire and explosion hazards of solid waste disposal facilities, taking into account current trends in the introduction of biogas (methane) collection and utilization systems. Methane is considered an alternative energy source for power plants. The authors determined the initial and limiting conditions of the mathematical apparatus of the method of combating fire and explosion hazards of solid waste disposal facilities based on the results of analysis and synthesis of factors of occurrence and spread of man-caused danger, existing mathematical models, and methods of counteracting man-caused danger. This is the basis for the further development of appropriate emergency response techniques. During the analysis, the authors found that humidity, the temperature of the landfill (household waste), the presence of sufficient oxygen at some point in time initiate the formation of explosive concentrations of methane in the array and contribute to the spread of hazards in landfills or dumps. The specific weight of the organic component, the value of the density of the array, the height of the landfill affect the process of counteracting the danger, namely the prevention of dangerous events and prevention of emergency from the object to the highest level of distribution (local level), primarily in the first group priorities, such as the number of victims and injured civilians and specialists of the units of the State Emergency Service of Ukraine. The team of authors has defined a system of equations of connection of the existence of the mathematical device taking into account initial and boundary conditions. A system of communication equations is determined taking into account the initial and boundary conditions of the mathematical apparatus, which allows to further develop a control algorithm for emergency response related to fire and explosion hazardous landfills close to settlements.

Fire and Explosion Hazards Due to Medical Oxygen Handling During Coronavirus Pandemic

With the continued outbreak of the coronavirus and the increase in the need for medical oxygen, it became necessary to take all measures for the safe handling of gas. Oxygen is very reactive and behaves differently to air, compressed air, nitrogen and other inert gases. Medical oxygen, at high pressure, from a cylinder, can react violently with hydrocarbons such as oil and grease which may be used mistakenly in cylinder valve or regulator. The oxidation products are a potentially explosive hydroperoxide. Nearly all materials including rubber, textiles, and metals will burn vigorously in the presence of oxygen. Atmospheric air contains nitrogen 78%, oxygen about 21% and with 1% remaining including a variety of other gases like carbon dioxide and argon. Even a small increase in the oxygen level in the air to about 24% can create a dangerous situation. It becomes easier to start a fire, which will then burn hotter and more fiercely than in atmospheric air and may be impossible to put the fire out. Increase the concentration of oxygen due to leaking valve or hose in a poorly ventilated room or in confined space can quickly create a dangerous level.

Toxic Gases in Mining

Rapid detection of causes of mining accidents leading to emergencies is to search the efforts. Controlling fires and gas leaks provides an immediate approach to rescue work for fatalities or injuries and detecting who needs resuscitation outside the mine. Evacuation and recovery operations should be guided by continuous monitoring of the mine environment due to fire and explosion hazards. The main toxic gases in mines are carbon monoxide (CO) and carbon dioxide (CO2); flammable gases are methane (CH4), CO and hydrogen (H2); suffocating gases are CO2, nitrogen (N20) and CH4; and the toxic gases are CO, nitrogen oxides (NOx) and hydrogen sulfide (H 2 S).

Fire and Explosion Hazards Associated with Electrostatic Powder Coating

This paper presents fire and explosion hazards during electrostatic powder coating, and describes the course of the process as well as the characteristics of powder coating as a combustible material. Potential sources of ignition that could initiate a fire of a dust layer or an explosion of a dust-air mixture have been identified. The minimum requirements and recommendations raising the level of safety in the area of coating installations are presented.

Mental health of chemical workers: violation risk factors

Aim. To study the structure of psychosocial maladjustment in chemical workers and assess the contribution of industrial and non-industrial risk factors in the formation of mental illness. Methods. It was analysed of hygienic assessment of the leading harmful production factors chemical, physical, factors of severity and intensity of labor. During the periodic medical examination, the mental health status of 1,226 people was examined, with a focus on professional experience, mental hygiene aspects of production factors, as well as individual and personal characteristics of employees. Confidence intervals and standard errors estimating, the logistic regression models fitting were performed using R Statistical Software with significance level 0.05. Results. The working environment hazards in organic synthesis included chemical risk factor, continuous noise exceeding the permissible exposure limit, emotional stress and life-threatening conditions (fire and explosion hazards in the work). The general assessment of working conditions was performed using clauses 5.15.11 P 2.2.2006-05-harmful working conditions of the second-third degree (3.23.3). Working conditions at all stages of the manufacturing process of pyroxylin powders were assessed as harmful to the third-fourth degree (3.33.4), including the chemical factor, the severity and intensity of work, fire and explosion hazards in the work. It was revealed the dependence of the development of psychosocial maladjustment on non-work-related factors (such as the level of education, marital status), conditional work-related factors (level of material security). Also, the dependence of the structure of pre-existing mental health condition on the work-related and developmental characteristics (work experience) of labor in chemical production was found. Conclusion. Working conditions in the studied industries correspond to the 3rd harmful class, 2nd and 3rd degrees in the production of organic synthesis (3.23.3), while at the production of pyroxylic powders, it is close to dangerous (3.33.4); the structure and risk of the developmental process of employee maladjustment are determined by the feature effect of workplace hazards.

Fire and explosion hazards of 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide

The decomposition of [EMIM][Tf2N] is endothermic in a nitrogen atmosphere but is exothermic in an air atmosphere.