Fire and Explosion Hazard during Depressurization of Equipment with Ammonia


The statistics of fires and explosions of ammonia in the sphere of its circulation (production, storage, use) indicate the relevance of studies aimed at preventing emergency situations, localization, and elimination of accidents consequences. Equally important are studies on the development of assessments of accidents consequences associated with the release and spillage of ammonia from the equipment in various aggregate state. When ammonia is released, the resulting mixture of the product with air can vary in density from the formation of gas-air clouds with a density below the air density to buoyancy and excess air density, depending on the release conditions (pressure and temperature in the equipment; the sizes of the hole through which ammonia enters the surrounding space; the location of the hole in the equipment (gas or liquid phase). When the liquid ammonia leaks out, the spills are formed, from the surface of which the product evaporates especially rapidly in the first moments after the spill.

Based on the computational and analytical studies, the design schemes and formulas were proposed for determining the parameters of the explosion: excess pressure and impulse of the undisturbed (incident) and reflected from the obstacles of the blast wave, as well as the nature of the destruction depending on the distance from the epicenter of the explosion, caused by the depressurization of equipment with ammonia. An accident scenario is considered, according to which the ammonia with a mass of 100 kg, when depressurizing, breaks out from the equipment of an industrial refrigerator. Ammonia vapors mix with the air to form a cloud that ignites and explodes. As an example, the overpressure and impulse during explosion of ammonia at a distance of 30 m from the epicenter of the explosion were determined. According to the empirical formula for estimating the distances from the epicenter of the explosion to a given place, the levels of the consequences of building destruction (complete, medium, small, moderate damage) can be established.

1. Vogman L.P., Sibirko V.I. Fires at industrial cold stores and refrigerating installations. Statistical evidence and examples. Kholodilnaya tekhnika = Refrigeration equipment. 2013. № 11. pp. 56–60. (In Russ.).
2. Vogman L.P. Features of ammonia physicochemical firehazardous, explosive properties and fire risk of facilities in which it is used. Kholodilnaya tekhnika = Refrigeration equipment. 2020. № 3. pp. 30–37. (In Russ.).
3. Ivanov Yu.A., Strizhevskiy I.I. Liquid ammonia storage and transportation. Moscow: Khimiya, 1991. 71 p. (In Russ.).
4. SP 12.13130.2009. Determination of categories of rooms, buildings and external installations on explosion and fire hazard. Available at: (accessed: March 20, 2021). (In Russ.).
5. Sofin A.S., Buynovskiy S.A., Marukhlenko A.L., Shalaev V.K. The Digital Transformation of Industrial Safety, the Line of Russian Software Products TOXI+. Bezopasnost Truda v Promyshlennosti = Occupational Safety in Industry. 2020. № 9. pp. 36–42. (In Russ.). DOI: 10.24000/0409-2961-2020-9-36-42
6. Sofin A.S., Agapov A.A., Buynovskiy S.A., Kanygin P.S., Avdeev A.S. Experience in Implementing a Real-time Accident Forecast System TOXI+Prognosis for the Production of Ammonia and Сarbamide. Bezopasnost Truda v Promyshlennosti = Occupational Safety in Industry. 2020. № 12. pp. 66–73. (In Russ.). DOI: 10.24000/0409-2961-2020-12-66-73
7. Safety rules for ammonia refrigeration units and systems: federal norms and rules in the field of industrial safety. Ser. 09. Iss. 49. Moscow: ZAO NTTs PB, 2019. 90 p. (In Russ.).
8. PB 09-579—03. Safety rules for surface warehouses of liquid ammonia. Ser. 09. Iss. 17. Moscow: ZAO NTTs PB, 2019. 76 p. (In Russ.).
9. Methodology for modeling the spread of accidental emissions of hazardous substances: Safety guide. Ser. 27. Iss. 11. Moscow: ZAO NTTs PB, 2020. 128 p. (In Russ.).
10. Taubkin S.I. Fire and explosion, features of their expertise. Moscow, 1999. 600 p. (In Russ.).
11. Beyker U., Koks P., Uestayn P., Kulesh Dzh., Strelou R. Explosive phenomena: assessment and consequences. Moscow: Mir, 1986. (In Russ.).
12. Vogman L.P., Mochalova T.A., Taratanov N.A. Theory of Combustion and Explosion. Moscow: Kurs, 2019. 224 p. (In Russ.).
13. Knunyants I.L. Brief chemical encyclopedia. In 5 parts. Moscow: Sovetskaya entsiklopediya, 1961–1967.
DOI: 10.24000/0409-2961-2021-10-27-30
Year: 2021
Issue num: October
Keywords : calculation depressurization accident parameters shock wave ammonia
  • Vogman L.P.
    Dr. Sci. (Eng.), Chief Research Associate, FGBU VNIIPO EMERCOM of Russia, Balashikha, Russian Federation