Gaëlle Fontaine, Centrale Lille France
Tests assessed smoke and fire behaviour of cross-laminated timber under different oxygen concentrations. Cross-laminated timber is a sustainable building material made from dried wood sections bonded by adhesive. Tests used ISO 5660-5 equipment, which enables reduced oxygen atmospheres, and 40 mm thick, 100 mm squares of spruce – polyurethane glue plywood. Results showed that reduced oxygen concentrations did not impact time to ignition and did not significantly reduce peak heat release rate down to 15% oxygen at 50 kW/m². Below that level, no ignition occurs but smoke production significantly increases. Carbon monoxide was much higher with non-flaming (smouldering) decomposition, as were volatiles from incomplete combustion (acetaldehyde, formaldehyde) and smoke particles were less numerous but much smaller (<0.03µm).