Fire Safety Science Digital Archive

Tests have been made in a small compartment to examine the effect of the presence of PVC with a cellulosic fuel fire on the toxic gases evolved under different degrees of ventilation. When the ventilation was small, as might be provided by a fanlight, hydrogen chloride was evolved from the PVC at a low rate, 30 min or more after the evolution of carbon monoxide from the cellulosic fuel, which occurred a few minutes after ignition. When the ventilation was larger, as might be provided by an open door, hydrogen chloride was evolved almost as quickly as carbon monoxide and in comparable amounts. Wben combustion of the PVC was complete, the hydrogen chloride evolved was equivalent to the chlorine content. However, the amount of hydrogen chloride produced by the combustion of, say, a PVC wallpaper, would not add much to the toxic risk due to the carbon monoxide formed by the combustion of the cellulosic content of a furnished room. Further tests are in progress to examine the effect of scale on the combustion processes and to test the feasibility of determining the rate of evolution of hydrogen chloride from the temperatures of surfaces within the compartment on fire.