This study describes a thermal imaging technique for measurement of a two-dimensional temperature field on the surface of a porous textile material which offers a high degree of thermal and spatial resolution in a non-intrusive manner. A PC-based system for image processing and analysis was developed for extracting thermal data from video images. Programming scripts were added to a commercial software package for augmenting its capabilities for automated acquisition of multiple and sequential thermal images, and for digital image processing. An optimum image smoothing routine based on histogram analysis is described for elimination of noise in thermal images with minimum degradation of data.; Transient temperature gradients on 100 percent cellulosic fabrics were measured under simulated cigarette exposure to explore the conditions leading to initiation and spread of smoldering. A series of cotton duck and upholstery fabrics were tested to evaluate the effect of fabric weight and alkali metal ions (sodium and potassium) on smoldering. Empirical data are presented in terms of peak surface temperature values and area within the isotherm curves to examine the influence of fabric properties on smoldering behavior. It was found that when the representative temperature in the smoldering zone is greater than 450{dollar}spcirc{dollar}C, the smoldering spread is maintained. Peak surface temperature and isotherm area measurements in the case of duck or canvass-type fabrics do not show any change in smoldering proclivity due to lower fabric weight and removal of alkali metal ions. This finding is in contrast to previous reported results showing reduction in number of smoldering ignitions for lighter-weight and washed duck fabrics. The results for upholstery fabrics, however, do suggest mitigation in smoldering with the removal of cations. Typically, the upholstery fabrics attained lower surface temperatures and reduced isotherm area. The washed upholstery fabrics did not sustain smoldering, indicating a reversal in smoldering proclivity.; The technique described here can also lend itself to future studies that include other fabrics across a broader spectrum of construction parameters representative of commercial upholstery fabrics and assemblies of furniture components including foam.
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