Some Reasons for the Violation of the Intumescent Coatings Quality

Abstract

The coke foam formed from the intumescent paint at the beginning of the fire effect is a good heat insulator and allows to protect the building structure elements from critical heating (from 500 °C) for some time. However, violations of technology on the real object can cause coking defects. And an insufficiently accurate assessment of the quality of the intumescent coating and foam in the laboratory can endanger the fire hazard of an object at risk. There are oversimplifications, limitations, and uncertainties in the existing laboratory procedures for testing fire-retardant properties of the intumescent paints. In this regard, many problems arise. The main property of the intumescent paint is tested under the influence of fire, that is, after the formation of the coke foam. Therefore, the fire test should be carried out only after the coating is completely ready at the facility. Аlso the area of the test coating should be significantly larger (20–80 cm2) than that of laboratory samples, since the functioning of paint and foam in real conditions is somewhat different. Additional study is required of the number of properties and behavior of intumescent paints that are capable to cause hidden defects in the original coating and foam. The authors highlight two main factors that cause hidden defects: incorrect choice of the thickness of the intumescent paint layer and excessive dilution of it before applying. Currently, the regulatory documentation does not regulate such important properties of the coke foam as the density and thickness of the layer, which determine the structure fire safety. An important task of future research is to find the ways to quickly identify violations of paint manufacturing and application technology, which lead to a critical deterioration in the properties of the future coke foam. The ultimate goal of the study of the methodology of fire protection, the authors see in the development of a comprehensive technique for detecting hidden defects when testing fire-retardant properties directly at the object, at large areas of fire-retardant coating (20–80 cm2), with the subsequent restoration of this area if the intumescent paint passed the test.