Two bolts of cotton duck fabric that meet military specifications and the purchasing guidelines described by the National Institute of Standards and Technology (NIST) for use as a substrate in "Test Methods for Quantifying the Propensity of Cigarettes to Ignite Soft Furnishings" were tested with smoldering cigarettes to determine the effect of inter-bolt variations on cigarette ignition propensity test outcome. The test was designed around an ASTM method that calls for the control of all known test variables, except for those inherent to the fabric's manufacture. The ignitability of each fabric was determined by testing two sets of 48 replications for each of two experimental cigarettes. The two bolts of cotton duck fabric showed a statistically significant difference in ignitions, independent of environmental and experimental fac tors. Two additional bolts of cotton duck #4 were analyzed. Cigarette ignition test results and the physical parameters of the additional bolts offer evidence that the NIST specifications are difficult to meet and further that test results are extremely sensitive to fabric properties.

To determine the effect of inter-bolt variability of duck #6 fabrics on cigarette ignition propensity, four bolts of duck #6 fabrics purchased accord ing to guidelines described by the National Institute of Standards and Technol ogy (NIST) were used in testing the ignition propensity of two experimental cigarettes according to a test method proposed by NIST. Results for each of the cigarettes were highly dependent on the bolt used in preparing the mockup. Inter-bolt variability of cotton duck #6 fabric was found to produce a statisti cally significant difference in the ignition results for the same cigarette. The results support an earlier study performed with duck #4 fabric. Numbered duck fabrics are no longer manufactured in the USA. Use of imported duck fabrics might introduce additional variables to the cotton duck fabric proper ties that could well lead to an even greater variability in cigarette ignition pro pensity testing.

Fifty cellulosic upholstered furniture fabrics were purchased in the Richmond, Virginia area and tested to determine their ignition responses to eleven commercial cigarette brands. Six of the commercial brands (A-F) had been identified by the National Institute of Standards and Technology (NIST), using their cotton duck substrate test method, as having reduced ignition propensity. The six cigarettes had "unconventional" 4 characteristics deemed by NIST as likely to lower cigarette ignition propensity: smaller circumference, lower permeability paper, and/or reduced paper citrate. On the cotton duck fabrics, these cigarettes were extinguished frequently. On the fifty upholstery fabrics, the cigarettes rarely were extinguished. NIST also tested fourteen "conventional, "5 best-selling brands that their cotton duck test method classified as "strong" igniters. Five brands (1-5) tested here on upholstery fabrics were also major commercial brands of "conventional" design. Testing of the fifty upholstery fabrics and eleven cigarettes followed the protocol developed by NIST with exceptions that upholstery fabrics replaced cotton ducks and polyethylene film was not used between fabrics and foam. Standard ANOVA analysis of ignition responses of the fifty upholstery fabrics showed that the two cigarette types, A-F and 1-5, were statistically similar: the differences in igni-'Current address: KC Automation, Inc., Richmond, VA. 'Current address: Philip Morris, Inc., Richmond, VA. 3Author to whom correspondence should be addressed at: Brown and Wilhamson Tobacco Corporation, PO. Box 630, Dinwiddie, VA 23841-0630. 4Filter cigarettes of 97-120 mm length and 17-22 mm circumference. 'Filter cigarettes of nominal 85 mm length and 25 mm circumference. Downloaded from 414 tions reported by NIST using cotton duck as the test fabric were not found with this broad range of actual upholstery fabrics. Differences in ignition responses among the fabrics did range from igniting in all tests to not igniting in any test, and from igniting more frequently with the six "lower ignition propensity" cigarette brands to more frequently with the five "conventional" ones.

To examine the effects of soiling on the smolder potential of upholstered furniture, sixty-six used upholstery fabrics were collected in the state of Georgia and sections of each fabric were determined to be either "soiled" or "unsoiled." A soiled area is an exposed surface of the upholstery fabric, whereas an unsoiled area is not exposed. Each fabric's composition (cell ulosic, synthetic, or mixed fibers) was determined, and soiled and unsoiled samples from each fabric were analyzed for pertinent chemical and physical characteristics. For the majority of fabrics, the smoldering potential of the soiled areas did not increase with respect to the unsoiled areas. In fact, more fabrics exhibited a reduced (versus increased) tendency to smolder upon soiling. Six fabrics that smoldered in the unsoiled condition did not smolder in the soiled condition. This study confirms results reported on used upholstery fabrics collected in the state of Virginia. Statistical analysis performed on data from each study and the combined data showed that smoldering potential had a statistically significant correlation to fabric, but not to soiling. Two ions that play a major catalytic role in smoldering ignitions, sodium and potassium, showed increased levels in soiled areas of the cellulosic fabrics by approx imately 700 ppm and 480 ppm, respectively. These increases did not account for the observed changes in smolder potential. The increase in sodium and potassium ion levels for all sixty-six fabrics collected in Georgia were equiva lent to those of the sixty fabrics collected in Virginia. Calcium and magnesium ions did not increase between soiled and unsoiled fabric areas. Chloride and sulfate increased in the soiled samples compared to the unsoiled. Levels of nitrate and phosphate did not change with soiling.