Spontaneous ignition of linseed oil soaked cotton using the oven basket and crossing point methods
The oven basket method coupled with the Jones version of the crossing point method was used to test the following basket sizes with their respectful concentrations of linseed oil soaked cotton, 5cm (33.3%), 5cm (50%), 5cm (75%), 7.5cm (77%), 10cm (80%) with concentrations measured by weight. Some of the samples reached three different stages; ignition, smoldering or constant smoldering and flaming. The activation energies were 42.37 kJ/mol, 27.40 kJ/mol, 16.97 kJ/mol, 15.76 kJ/mol and 11.73 kJ/mol for the 5cm (33.3%), 5cm (50%), 7.5% (77%) and 10cm (80%) basket sizes. It was concluded that as the concentration and the basket size increased the activation energy decreased. The P and M values along with the reaction rate per unit volume were also calculated. The time to ignition increased as the oven temperature that each sample was tested at decreased and as oven temperatures approached ambient the time to ignition significantly increased topping 5.5 hours for the 5cm (75%) basket size.