Analysis of methods used to identify combustible gas and vapour-related factors contributing to explosions in the context of assigning explosion and fire safety categories to premises

Introduction. The authors have classified numerous publications, addressing the assignment of explosion and fire safety categories to premises, buildings and outdoor facilities, into the three groups: 1) sources of information that are in effect (including in-house and region-wide documents), sources that were in effect; 2) manuals and guidelines on category assignment; 3) publications that confirm (refute) or clarify some provisions, specified in regulatory sources. This article can be included into the third group of publications.

Goal. Analysis of different methods, used to identify the value of Z factor; identification of strengths and weaknesses of each method, development of recommendations on the application of these methods.

Objectives. The objective is to identify the substance-related factor contributing to explosions, use particular cases to demonstrate the efficiency of this or other identification method.

Results and discussion. The analysis of Z factor identification methods, describing the contribution of vapours of highly flammable liquids to an explosion, has proven that three types of procedures can be used to find the Z factor value:

• the method of tables (that uses the maximal possible tabular value of Z = 1; for gases and aerosols Z = 0.5; for vapours of highly flammable liquids Z = 0.3);

• the computational method based on a pattern of three-dimensional gas and vapour spreading on the premises; however, this method, if applied, may involve a high probability of errors due to numerous conditions limiting its applicability; hence, the unexplainable value of Z may exceed 1. Besides, the computational method is extremely laborious. Its application requires the clarification of conditions for its use;
• the graphical method (based on the dependency graph of Z on the X parameter). This method is the simplest and the most reliable one. When the graphical method is used to find the value of Z, the excess oxidant ratio must be taken as being equal to one, and the Х parameter must be calculated according to the following formula: Х = 0.99 Рs.v/Сst.c.

Conclusions. The graphical method, used to find the value of Z, is simple and reliable. When the Х parameter is identified, the excess air ratio is used: φ = 1.9, which leads to the underestimation of Z, the vapour-related factor contributing to explosions. To prevent the unreasonable underestimation of Z, the excess air ratio must be disregarded or taken as being equal to 0.99.

1. Technical Regulations on fire safety requirements : Federal Law No. 123-FZ of 22.07.2008 (as amended on 30.04.2021). (rus).

2. SP 12.13130.2009. Determination of categories of premises, buildings and outdoor installations for explosion and fire hazards. (rus).

3. ONTP 10-99. Norms of technological design for mechanical engineering enterprises. Definition of categories (classification) of premises and buildings of enterprises for explosion and fire hazard. Fire protection requirements. (rus).

4. NPB 105-03. Determination of categories of premises, buildings and outdoor installations for explosion and fire hazards. (rus).

5. ONTP 24-86. Determination of categories of premises and buildings for explosion and fire hazard. (rus).

6. SNiP II-90-81. Industrial buildings of industrial enterprises. Design standards. (rus).

7. CH 463-74. Instructions for determining the category of production for explosive, explosion and fire hazard. (rus).

8. CH 102-71. Fire safety standards of construction design of industrial enterprises and populated areas. (rus).

9. OST 90 015-39. All-Union norms of construction design of industrial enterprises. (rus).

10. Korolchenko A.Ya., Zagorsky D.O. Categorization of premises and buildings by explosion and fire hazard : study guide. Moscow, Pozhnauka Publ., 2010; 118. (rus).

11. Manual on the use of SP 12.13130.2009. Determination of categories of premises, buildings and outdoor installations for explosion and fire hazards. (rus).

12. Manual on the use of NPB 105-03. Determination of categories of premises, buildings and outdoor installations for explosion and fire hazards. (rus).

13. Khrunov V.A., Kasatkina V.I. Categorization of premises and buildings by explosion and fire hazard : methodical instructions. Ivanovo, Ivanovo GPU, 2016; 36. (rus).

14. Vodiev P.P. Definition of categories of premises and buildings for explosion and fire hazard. Ulyanovsk, UVAU GAI, 2009; 19. (rus).

15. Ovcharenko A.G., Smirnov V.V. Calculation of criteria for explosion and fire hazard of industrial premises. Biysk, AGTU im. Polzunova I.I., 2019; 27. (rus).

16. Hou J., Liu K. Theoretical models and experimental methods for determining the equations of state of silicate melts: Review. Science China Earth Sciences. 2019; 62(5):751-770. DOI:10.1007/s11430-017-9325-3

17. Cui Z., Yan Y., Liu Q., Zhao X., Xu X., Liu F. et al. Precise determination of the complex refractive index of low-dimensional materials by the resonator resonance method. Optical Materials. 2022; 131:112682. DOI:10.1016/j.optmat.2022.112682

18. Lang F.K., Xing Y.M., Zhao Y.R., Zhu J., Hou H.H., Zhang U.G. Experimental determination of residual stresses at the interface of polymers reinforced with carbon fiber. Composite Structures. 2020; 24(sup1): 33-47. DOI:10.1080/09243046.2014.937136

19. Habib F., Tocher D.A., Press N.J., Karmal K.J. Determination of the structure of terpenes by the crystal sponge method. Microporous and Mesoporous Materials. 2020; 308:110548. DOI:10.1016/j.micromeso.2020.110548

20. Lv Yu., Liang J., Wang B., Zhang H., Yuan W., Li Yu. et al. Influence of heat transfer and moisture transfer on the growth of mold on the inner surface of walls: a case study in Dalian, China. Modeling of Buildings. 2020; 13(6):1269-1279. DOI:10.1007/s12273-014-0200-9

21. Baratov A.N. Categorization of objects by fire and explosion hazard. Results of science and technology. Fire Protection : collection of scientific papers. Vol. 6. Moscow, VINITI, 1985; 41-68. (rus).

22. Baratov A.N., Pchelintsev V.A., Nikonova E.V. Improvement of the system of categorization of premises and buildings by explosion and fire hazard. Pozharovzryvobezopasnost/ Fire and Explosion Safety. 2001; 10(3):25-27. (rus).

23. Zemsky G.T., Vogman L.P., Maslennikov V.V., Zuikov V.A., Zenin V.A. Determination of the category of premises by fire and explosion hazard in which mutually reacting substances are handled. Pozharovzryvobezopasnost/ Fire and Explosion Safety. 1993; 4:28-31. (rus).

24. Shebeko Yu.N., Korolchenko A.Ya., Shevchuk A.P. On the principle of “maximum expected impact” when categorizing industrial premises by explosion and fire hazard. Pozharovzryvobezopasnost/Fire and Explosion Safety. 1992; 1(3):46-48. (rus).

25. Vasyukov G.V., Korolchenko A.Ya., Rubtsov V.V. On the problem of categorization of premises for storage and technical service of gas-balloon fire automobiles. Pozharovzryvobezopasnost/Fire and Explosion Safety. 2006; 15(1):25-29. (rus).

26. Kharlamenkov A.S. Categorization of gas boiler rooms on explosion and fire hazard. Pozharovzryvobezopasnost/ Fire and Explosion Safety. 2018; 27(11):70- 72. URL: https://elibrary.ru/item.asp?id=36576465 (rus).

27. Vogman L.P., Zemsky G.T., Zuikov V.A., Kondratyuk N.V., Zuikov A.V. Methodological approach to the definition of categories for explosion and fire hazard of premises and outdoor installations for the storage of fireworks of hazard classes I–III. Actual Problems of Fire Safety : materials of the XXVI International Scientific and Practical Conference. Balashikha, 2019; 155-157. URL: https://elibrary.ru/item.asp?id=38074288 (rus).

28. Zemsky G.T., Zuikov V.A. Classification of premises with the presence of volatile liquids. Fire Safety. 2013; 1:39-45. URL: https://elibrary.ru/item.asp?id=18875599 (rus).

29. Peisakhov I.L., Lyutin F.B. Atlas of diagrams and nomograms for gas-dust technology. Moscow, Metallurgya Publ., 1974; 116. (rus).

30. Calculation of the main indicators of fire and explosion hazard of substances and materials : manual. Moscow, VNIIPO EMERCOM of Russia, 2002; 33. (rus).

31. Korolchenko A.Ya., Korolchenko D.A. Fire and explosion hazard of substances and materials and means of extinguishing them : reference. Moscow, Pozhnauka Publ., 2004. (rus).

32. Zemsky G.T. Physico-chemical and flammable properties of organic chemical compounds : reference. Moscow, VNIIPO EMERCOM of Russia, 2016; 971. (rus).

33. Portola V.A., Lugovtseva N.Yu., Torosyan E.S. Calculation of combustion and explosion processes : study guide. Tomsk, Publishing House of Tomsk Polytechnic University, 2012; 108. (rus).

34. Smelkov G.I., Pekhotikov V.A., Ryabikov A.I., Nazarov A.A. To the issue of accumulator batteries fire safety. Occupational Safety in Industry. 2020; 5:56-62. DOI:10.24000/0409-2961-2020-5-56-62 (rus).

35. Nikulina Yu., Shulga T., Sytnik A., Toropova O. System analysis of the process of determining the category of premises for explosion and fire hazard. Research in the Field of Systems, Decision-Making and Management. 2021; 337:125-139. DOI:10.1007/978-3-030-65283-8_11

36. Shulga T., Nikulina Yu. Decision support system in the design of fire alarm systems. Research in the Field of Systems, Decision-Making and Management. 2022; 416:407-416. DOI:10.1007/978-3-030-95112-2_33

37. Glushkov D.O., Paushkina K.K., Pleshko A.O., Vysokogorny V.S. Characteristics of micro-explosive dispersion of gel fuel particles igniting in a high-temperature air environment. Fuel. 2022; 313:123024. DOI:10.1016/j.fuel.2021.123024

38. Okamoto K., Ichikawa T., Fujimoto J., Kashiwagi N., Nakagawa M., Hagiwara T. et al. Prediction of evaporative diffusion behavior and explosion damage in gasoline leakage accidents. Process Safety and Environmental Protection. 2021; 148:893-902. DOI:10.1016/j.psep.2021.02.010

39. Wang T., Zhou Yu., Luo Z., Wen H., Zhao J., Su B. et al. Behavior of the flammability limit of methane with the addition of gaseous fuel at different relative humidity. Technological Safety and Environmental Protection. 2020; 140:178-189. DOI:10.1016/j.psep.2020.05.005