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Approaches to assessing professional risk are considered for the example of a EuroChem facility. Deficiencies in the program for professional risk assessment outlined in Russian Handbook 2.2.1766–03 are analyzed. This program takes no account of the worker’s age, experience, and overall health. Likewise, statistical data regarding workplace injuries and morbidity are ignored. At the same time, the method of calculating the individual professional risk proposed by the Klin Institute of Labor Protection and Working Conditions permits calculation of the risk for 66 workers and determination of an integral index of professional risk within the organization. Comparison of risk assessments by method in Handbook 2.2.1766–03 and the Klin method shows that the class of working conditions affects the individual professional risk but is not the determining factor.

In this paper, we present the experimental results of complex studies of the sensitivity to mechanical effects and detonation parameters of metalized explosive compositions based on weakly phlegmatized HMX and RDX. Powders of titanium, zirconium, and their hydrides and deuterides were used as fillers. The introduction of these components in an amount of up to 20 wt % is established to contribute to some increase in fire hazard and sensitivity of the compositions in handling them. Estimates show that an increase in the detonation parameters of the mixtures observed in some cases may be due to the chemical reactions of the additives with explosion products in the detonation wave front.

An algorithm is proposed for determining the target development scenario for an industrial emergency arising from terrorist attack or other unsanctioned actions, by assessment of the threats to critical system elements. Criteria are selected for ranking possible scenarios. The target scenario is identified by multicriterial optimization—specifically, by means of the displaced ideal in fuzzy decision making. By means of the algorithm developed for fuel and power companies, a hazard class may be assigned to any unsanctioned intervention, and improved security measures may be developed.

Two explosive compositions ISU-4K and ISU-5R based on ammonium nitrate with added coke, diesel fuel, and rubber crumbs are tested so as to establish their sensitivity to mechanical and thermal perturbations. The flash point corresponding to 60-s delay is established. The kinetic parameters of thermal disintegration of the explosives are determined. The information obtained may be used in compiling standard documents (of GOST, OST, TU, VTU, and other types) and writing industrial regulations.

@Abstraction limits of flame propagation are determined for 13 glycols, as well as their enthalpy of formation and enthalpy of combustion. These characteristics depend on the number of carbon atoms in the glycol molecule. The combustion parameters are calculated for vapor–air mixtures of glycols and monoatomic alcohols, in the case where P = 1 atm and V = const. The adiabatic combustion temperature of mixtures of limiting and stoichiometric composition does not depend on the number of hydroxyl groups in the alcohol molecule. The explosive pressure of glycol is slightly higher than for monoatomic alcohols.

The enthalpy of formation and combustion is calculated for 15 aliphatic amines by various methods. These characteristics depend on the number of carbon atoms and the number of amino groups in the amine molecule. The combustion parameters are calculated when P = 1 atm and V = const, for mixtures of aliphatic amines with air. The adiabatic combustion temperature of mixtures of limiting composition is practically independent of the amine structure. The calculated values of the maximum pressure exceed 1000 kPa.

The combustion temperatures of mixtures of 43 highly inflammable and combustible liquids with air are determined at constant volume, at concentrations corresponding to the upper and lower limits on flame propagation in conditions of constant pressure. The results show that these temperatures are approximately the same for different materials. The combustion temperatures of air–vapor mixtures containing a safe (according to handbook data) concentration of retardant may exceed that of the limiting compositions. This raises doubts regarding the validity of handbook data obtained in tests in small chambers. The limiting combustion temperatures of mixtures containing air and the gases and vapor formed in coke production are calculated; these results are required for reliable determination of the retardant concentrations of inert gases.

The maximum explosion parameters of flammable and combustible liquids are determined, as well as the conditions to which they correspond. The parameters required to assess the saturated vapor pressure of multicomponent mixtures of such liquids are calculated. Programs are developed for calculating the mass of exploding material and the pressure rise in buildings on explosion, on the assumption of stepwise evaporation. Analysis reveals the deficiencies of the method currently used to calculate the mass of the exploding vapor from flammable and combustible liquids and the pressure rise in buildings on explosion. The maximum explosion parameters are calculated for mixtures of flammable liquids with air, and the concentrations corresponding to such parameters are determined. The results for the saturated vapor pressure of flammable liquids according to the Antoine and Clapeyron-Clausius methods are shown to be the same. A method is developed for calculating the parameters of the Antoine method by means of the heats of vaporization of flammable liquids on the basis of solution of both the Antoine and Clapeyron-Clausius equations. By the proposed method, the heats of vaporization of butylbenzene and pyridine are calculated; these values are not found in existing handbooks. Corrections are introduced in the program for calculating the quantity of material involved in the explosion of flammable liquids and the corresponding pressure rise in buildings, on the assumption of stepwise evaporation. The refined model may change the assignments of explosion- and fire-safety classifications for buildings and technological equipment.

The theoretical basis of laboratory shock sensitivity test procedures (methods of critical energies and critical pressures) of energetic materials is given. The quantitative criterion of explosive risk has been introduced and calculated by the example of model hydrogenous explosive material.

For mixtures of air with highly inflammable vapor, the maximum explosive pressure corresponds to superstoichiometric fuel concentrations. The maximum explosive pressure is similar for different classes of compounds and considerably exceeds the handbook values. This must be taken into account in predicting the consequences of explosions.