Cleanliness is one of the most essential virtues needed for a healthy lifestyle. While there have been several attempts made to characterize the cleanness of food, water and air by quality monitoring, there has been very little attention given to the cleanness characterization of clothing. Clothing worn next to the skin is easily contaminated by solid particles and fluid substances picked up from the surrounding environment and the skin surface. The fluid contamination could be either aqueous or oily in nature. Human sweat and sebum are one of the major constituents of oily organic soils found in worn clothing. Studies show that oily organic contaminations tend to remain in the clothing even after laundering, thereby creating malodors. While there are several industry established standards to evaluate visible solid contamination such as dust, dirt and colored stains, measuring the amount of invisible oily contaminations has been difficult. Moreover, many of the cleanness evaluation methods are subjective. This exploratory research aimed at measuring the level of sweat and sebum soiling in textile fabrics. Due to the affinity of ozone towards the unsaturated components of sebum, the feasibility of using the reaction rates of ozone as a metric to quantify the level of organic soiling in clothing was tested. The fabrics selected for this study were representative of the commonly used fiber composition in activewear and innerwear. The sweat and sebum used for fabric soiling were synthetic in nature. The fabric swatches were soiled with synthetic sebum at two extreme levels of soiling (0.3% and 1% of the fabric weight). A lab built four-chamber ozonation equipment was used for the experimentation with ozone. The reactivity of ozone with the soiled fabrics was measured in terms of ozone concentrations in ppb. The data obtained was plotted against time and the slopes were recorded. The plots showed a significant difference in the slopes indicating that the rate of ozone reactivity varied with the level of soiling. The slopes were steeper for higher levels of soils, particularly in the cotton samples. There was also a marked difference in the reaction rates between the cotton and polyester fabrics at the same level of soiling. The results obtained from the study fulfilled the hypothesis and looks promising for developing an objective method of measuring cleanness of clothing. Moreover, an adjunct qualitative study was conducted to assess the sensitivity of the human odor sensor to acknowledge the difference in the level of soiling through sensory analysis. The results from the study substantiated the need for an objective method of cleanness measurement. / text