Volatile point of dust mixtures and hybrid mixtures

A novel flammability parameter (Volatile Point, VP) of pure dusts, dust mixtures and hybrid mixtures is here measured and proposed as a key parameter to assess flammability. This parameter is defined as the temperature at which volatiles are produced generating a flammable vapor mixture, similarly to the Flash Point defined for flammable liquid substances and mixtures. Measurements of VP were performed for niacin, lycopodium, anthraquinone, and their mixtures. The VP values of suspensions of these dusts in glycerol were measured as well. Results show that the VP of the mixtures may be lower than the VP of the pure compounds, suggesting that a synergistic behavior takes place which should be carefully considered when storing and handling dust mixtures and hybrid mixtures.