Comparative Analysis of the Flammability Characteristics of Historic Oak Wood from 1869 and Contemporary Wood

The tests are aimed at demonstrating the flammability of historic (old) oak wood compared to the fire resistance of modern oak wood. The tested wood has a similar density and a similar degree of grain. The tests aim to show whether historic wood behaves significantly differently than modern wood during a fire. The dried weighed, and sized samples were subjected to a fire resistance test in an MLC calorimeter using a thermal radiation flux of 35 kW/m² and 50 kW/m². Six samples of modern wood and twelve historic wood with similar density and degree of surface damage were selected for testing. Analyzing the results of most flammability parameters, it was shown that old wood, regardless of the surface condition and heat intensity, is characterized by lower values of heat release rate (HRR), total heat released (THR), effective heat of combustion (HOC) and mass loss (ML).). The average ignition time of historic wood at an intensity of 35 kW/m² is faster than that of new wood by 28.5%, and at 50 kW/m² even by 54%. However, such a fast ignition time does not negatively affect the weight loss of historic wood compared to modern wood, as it is caused by extensive surface damage. The times for samples to ignite and extinguish in the case of historic wood are shorter than for modern wood. These values, however, do not negatively affect the remaining flammability parameters of the analyzed wood.