Introduction: Washing textiles removes dirt and micro-organisms, and environmental policies and strategies encourage the use of low temperature washing programmes. Lowering the temperature raises serious concerns as the positive environmental impact must be weighed against the hygienic aspect of the washed laundry and its impact on health. The reduced washing temperature can be compensated with a chemical agent and additional antimicrobial effects can be achieved during the subsequent drying process. Aim: The purpose of this master’s thesis is to investigate the impact of different drying methods on the effectiveness of ensuring textile hygiene after a previous low-temperature domestic wash at 30°C. Methods: The efficacy of removing standard strains of Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus hirae and the yeast Candida albicans from cotton fabric samples was analysed after a low-temperature wash at 30°C and four different drying scenarios: air drying (laminar vertical chamber), sun drying (Xenotest), low temperature drying at 40°C (new dryer model) and high temperature drying at 70°C (traditional dryer). Results: The results indicate that washing at low temperature is an effective measure to eliminate microorganisms, but not to a sufficient degree according to the requirements of the SIST EN 16616:2015 standard. Drying is an important additional measure to improve laundry hygiene, with drying at high temperature (70°C) proving to be the most effective. Drying at a low temperature (40°C) achieved a comparable reduction in microorganisms, while drying in the Xenotest was the least effective. Of all the microorganisms tested, C. albicans proved to be the most sensitive to drying, while E. hirae was the least sensitive. Ultimately, all drying scenarios were effective in reducing the number of microorganisms after the low temperature wash at 30°C. In accordance with the requirements of the SIST EN 16616:2015 standard, all drying scenarios achieved a reduction in bacteria of more than 4 log CFU/cm² and yeast of more than 3 log CFU/cm². Discussion and conclusions: Although washing at 30°C does not eliminate all microorganisms, it can be concluded that the combination of washing and drying at low temperatures is an effective solution to achieve an adequate reduction of microorganisms when processing household linen under normal conditions. This result is significant as it represents a balance between the effective removal of microorganisms and a sustainable approach to laundry washing.
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