Fire resistance of olive leaf panels with fire retardant coatings: Preliminary findings

Olive tree pruning waste represents a significant agricultural byproduct in Mediterranean regions. It can be regarded as a sustainable and cost-effective alternative resource to other traditional materials for buildings. It is necessary to evaluate the flammability of these materials, according to building regulations. In this preliminary study, several fire-retardant coatings were applied to the materials obtained from olive leaves mixed with a natural adhesive. The coatings included cement-based layers, hydraulic lime, gypsum plaster, intumescent varnishes containing phosphate-based compounds, and graphene-based paints. Treated samples were subjected to flame spread tests to determine their fire resistance properties according to Standard EN ISO 11925-2. The potential of using olive leaves waste as a building material when combined with appropriate fire-retardant coatings is highlighted. The findings suggest that such treatments contribute to mitigating fires and promote the sustainable use of agricultural byproducts in buildings. By applying the coatings, the fire resistance increases significantly compared to untreated samples. The ceramic coatings provided the highest level of protection by reducing the flame spread rate and increasing the time to ignition. Additionally, the treated samples exhibited increased char formation, reducing heat transfer, and delaying combustion. Further research is recommended to optimize the formulations and application methods for large-scale implementation.