Press Release: New study published on sooting of hot-dip galvanized steel components

Rheurdt, November 4th, 2025 – The Association for Fire Protection Coatings (IGSB), together with partners, has published a scientific investigation in the specialist medium “Bauingenieur” that provides new insights into the influence of soot on the emissivity of hot-dip galvanized and non-galvanized steel profiles. The fire tests were carried out according to the standard temperature/time curve (STC) on HEB 320 steel profiles, each with and without previous sooting. The results show that sooting leads to significantly higher emissivity. The publication highlights the importance of taking sooting effects into account when calculating steel temperatures in the event of a fire and provides important insights for the application of design rules.

“The findings are an important contribution to the realistic design of steel structures in the event of a fire,” emphasizes Dr. Sebastian Moschel, chairman of the IGSB and co-author of the study. “The influence of sooting should be taken into account in the future, particularly when evaluating hot-dip galvanized steel components exposed to fire. With this study, we are making an important contribution to a better assessment of the thermal boundary conditions in the event of a fire. Our results underline that even seemingly secondary factors such as sooting have a measurable influence on structural fire protection and should not be underestimated.”