reaction can be observed in the form of narrow and very sharp peaks, also observed during the DSC analysis of typical explosives, e.g., ANFO. Explosive AN mixtures include, i.e., oils, greases, rubbers, metal dust, or acids [2; 3; 4; 5; 6]. Relatively sharp peaks are observed for several phenomena, such as the melting of crystalline bodies. However, the energy effect, unlike an explosion, is at least 1-2 orders of magnitude smaller. Therefore, it was decided to closely examine one of the potential causes underlying the uncontrolled progress of events. The research was carried out in accordance with the findings based on the analyses of numerous disasters, as well as on tests and results carried out and published by many experts previously dealing with AN-related issues. Plastics have long been ubiquitous in our surroundings. AN is the cheapest and most widely used agricultural fertilizer in the world, and, at the same time, a popular base for the production of explosives used in various mixtures applied in mining. The fact that the materials in question can melt in a fairly similar temperature range prompted us to conduct such studies. They pass into the liquid phase almost simultaneously, which greatly facilitates the formation of an explosive mixture. From among numerous plastics, we selected those that have a melting point within the appropriate range and of which items, used and potentially used where AN is stored or applied, are produced. Potential reduction properties of the molten material or of its thermal decomposition products were the second selection factor. The results of the research clearly showed that the choice was right. The first of the selected polymers was the aforementioned polyvinyl chloride (PVC); its chemical formula is (-[CH\({}_{2}\)CHCH])-\({}_{n}\). PVC is a popular synthetic thermoplastic polymer from the group of vinyl polymers. Due to different properties, two forms of this material can be distinguished: unplasticized PVC (uPVC), also referred to as hard PVC, and plasticized PVC (PVC-P), also referred to as soft PVC. From the chemical point of view, they differ mainly in terms of the number of added plasticizers. Due to high chemical and mechanical resistance, PVC is widely used in various industries. As it comes to the agricultural industry, PVC is most frequently applied in the production of irrigation pipes and pipes in sewage and water supply systems inside farm buildings. Concerning the safety of AN storage, the first of these applications is crucial because elements of water supply networks on farms may be situated near other materials. Additionally, PVC is used in the construction of large-area tents. It may also be applied in construction materials as well as in equipment of utility rooms, such as door frames, window frames, and gutters. Furthermore, PVC can be used in electrical wiring insulation, packaging, or as a cover for coated fabrics. In comparison to most polymers, PVC has a relatively high flash point and auto-ignition temperature. Moreover, the high limiting oxygen index (LOI) value, 50% for uPVC and 21-36% for PVC-P (depending on composition), suggests that this polymer is a fire-resistant material and requires a strong external heat source for ignition. PVC, while burning, produces much less heat than most organic materials. Therefore, it is believed that the heat released by combustion may be insufficient to initiate ignition of nearby materials (26 MJ/kg). Moreover, during the combustion, the behavior of PVC also differs from that of most popular polymers. No dripping occurs while melting; instead, the surface becomes charred, which, together with the hydrogen chloride released during decomposition, may limit the spread of fire. From the chemical point of view, the fact that carbon monoxide, carbon dioxide, hydrogen chloride, and water vapor are main products of PVC combustion is also very important. During the laboratory combustion of the material, no observable amounts of gaseous chlorine and phosgene are released.