Factors Involved in the Ignition of Cellulosic Upholstery Fabrics By Cigarettes

Abstract

Experimental cigarettes that approach the lower practical limits in tobacco density and circumference of that which can be produced were tested for their ignition propensity in three mock-up furniture configurations on 33 cellulosic fabrics over polyurethane and untreated cotton batting substrates. The three configurations were: flat, L or tight crevice-cigarette placed at the junction of the horizontal and vertical panels, and V or open crevice-cigarette placed in the crevice between a vertical panel and a second panel at a 20° angle. The cigarette heat outputs ranged from about 700-1,500 cal/cig and the fabrics covered the typical types (prints, weaves, velvets) and weights from 4.0-22.8 oz/yd². For 18 of 33 fabrics over polyurethane all cigarettes in all configurations produced either no ignitions or 100% ignitions. The most important variables which influenced ignition propensity over polyurethane were yarn "smoldering proclivity" which showed a statistical correlation with the alkali metal content of the fabric, fabric density and fabric weight. Cigarette heat output influenced ignition propensity over polyurethane only in the L and V configurations and only over a narrow range of weighted fabric characteristics. Over cotton bat ting, all cigarettes produced nearly 100% ignitions in the L and V configura tions. In the flat configurations over cotton batting the combined K⁺ and Na⁺ level of the fabric and fabric density showed a significant effect whereas cigarette heat output again had an effect only over a narrow range of weighted fabric characteristics.