Abstract
A method to determine the free burning rate of cigarettes is described. After conditioning the cigarettes are ignited one by one with an electrical heating device and then placed, in vertical position, in boxes of sheet metal and with sliding glass windows. Thus each cigarette is protected from draughts or from heat given off by adjacent cigarettes. A system of holes in the bottom and cover of the boxes permits the necessary air renewal. The time required for the free burning of a given length is determined visually with the aid of a stopwatch. The result of the test is expressed as the weight of tobacco burned per minute and per cigarette. As indicated by results presented in the paper, the method is suited for quality control work involving machine made cigarettes, as well as for the evaluation of different tobacco samples or cigarette papers. If certain precautions are met, the test can also be applied to hand-made cigarettes. The free burning rate was found to be largely determined by the kind of paper and the type of tobacco used. On the other hand, no decisive influence of the arrangement of the tobacco shreds within the cigarette could be observed as long as normally filled cigarettes were used for the tests