Intrinsic Smoke Properties and Prediction of Smoke Production in National Bureau of Standards (NBS) Smoke Chamber

Smoke production in a smoke chamber is characterized by the accumulation of smoke and the continuous consumption of oxygen leading to a vitiated atmosphere. However, a method is proposed to predict the smoke evolution in a smoke chamber at 25 kW/m(2) by using material properties calculated from a cone calorimeter, as already shown in a previous article. These properties represent the ability of a material to produce smoke at a specific mass loss rate. The influence of a flame retardant on these properties can be used as a quantitative measurement of its action on smoke production. These properties can be calculated at another heat flux than 25 kW/m(2). The knowledge of the curve mass loss rate = f(time) in a smoke chamber is still required, but this curve is close to that measured in a cone calorimeter at the same heat flux. The results prove that the smoke production in a smoke chamber and cone calorimeter is qualitatively similar, i.e., the decrease of oxygen content in a smoke chamber has no influence on smoke (at least as long as optical density does not exceed 800).

Automated summary

Smoke production in a smoke chamber is influenced by the accumulation of smoke and continuous oxygen consumption, but a method using material properties calculated from a cone calorimeter can predict smoke evolution. The properties indicate a material's capability to produce smoke at a specific mass loss rate, and the effect of flame retardants on these properties can measure their impact on smoke production. Although knowing the curve of mass loss rate = f(time) in a smoke chamber is necessary, it closely resembles that measured in a cone calorimeter at the same heat flux. The similarity between smoke production in a smoke chamber and cone calorimeter is qualitatively demonstrated, with oxygen content reduction in the smoke chamber having no influence on smoke until the optical density exceeds 800.