an investigation of domestic laundry in europe - habits ... - SIFO

More documents

Recommendations

Info

70An investigation into the domestic laundry habits in Europesoiled laundry was used. In his research Raschle even found an increasednumber of bacteria after washing dirty laundry at 30°C.- Chemical disinfection.In household laundering, chemical disinfection can be achieved using variousdetergent bleach components. Examples of the most commonly used chemicalsare tetraacetylethylenediamine/persalt combinations [4], percarbonate,perborate and sometimes dichloro-isocyanurate. Hypochlorite bleach in thelast rinse of the washing process or separately after the washing process alsoachieves thorough disinfection.High pH-values have a conserving effect: this means that generally, microorganismswill not be killed but their growth will be impeded. High alkalinedetergents are therefore assumed to have a positive effect on laundry hygiene.On the basis of chemical and physical theory, a strong synergistic effect betweenthe disinfection mechanisms is assumed.4.1.2 Approach and executionThe focus of the study is on the hygienic quality of laundry processes at lowwash temperatures (i.e.15°C and 30°C) and on the two most common washingprocesses in four European countries. The countries were chosen such thatdifferent regional situations are represented. The hygienic levels are evaluatedby assessing the microbiological counts of relevant microorganisms on naturallysoiled domestic laundry before and after washing.In a preliminary study, an inventory of micro-organisms on naturally soiledlaundry is made on the basis of literature. Thereafter a set of (pathogenic) micro-organismsthat may represent the hygienic quality of laundry is derivedfrom laboratory tests. Next laundry items are chosen in which the selectedmicro-organisms are likely to be found. Finally the level of hygiene (i.e. themicrobiological count) of naturally soiled laundry is determined before andafter washing under four different conditions. For this purpose an existing testmethod has been refined. In addition, the level of cross-contamination betweenlaundry items has been investigated, using original sterile textile samples.The hygienic properties of different European detergents have been assessedin separate tests. The results of the tests are compared to the results of alimited test of the level of hygiene of a real household wash.
Hygiene effects of laundry processes in Europe 714.2 Research design4.2.1 BackgroundThe hygiene effects of different laundry processes in Europe (Greece, Norway,Spain and the Netherlands) will be assessed in this research. The focus ison the hygienic quality of washing processes at low temperatures (i.e. 15°Cand 30°C) and on the two most common washing processes in each country ofinterest.Block et al. [5] recently developed a test method to determine the micriobicidaleffect of laundry detergents within a washing process. In this test, artificiallycontaminated micro-organism carriers are washed together with sterileballast fabrics in a normal washing machine under realistic conditions. After acomplete washing cycle, the surviving test organisms on the carriers are identified,and cross-contamination and contamination of the washing liquid areevaluated as well. Block states that this test method is suitable for simulatingrealistic household laundry conditions and uses relevant test organisms.The Block method uses artificially contaminated micro-organism carriers withhigh contamination levels. These high contamination levels allow for the calculationof viable reduction factors. The test organisms used are very specificand are selected with regard to their relevance to household conditions and onthe basis of existing proposals.The objective of the present study, however, is to assess the hygiene effect ofa washing process and not solely to determine the micriobicidal effect of thelaundry detergent. The fixation and aggregation of micro-organisms to soilparticles in real life situations is quite different from the artificial contaminationused by Block. Therefore, and from an even more realistic point of view,it is interesting to investigate the reduction (or cross-contamination) of microorganismson naturally soiled domestic laundry.The starting point of this research design is the Block method with some majormodifications. The microbiological count of relevant micro-organisms onnaturally soiled domestic laundry items will be determined in a laboratory testbefore and after washing. The wash load is filled with a sterile cotton baseload as in the Block method. The micro-organisms and laundry items are selectedon the basis of a literature study and from laboratory tests. Furthermore,cross-contamination of laundry items is determined by washing sterile pieces
Page 1:
• • • • • • • • •
Page 4 and 5:
2An investigation into the domestic
Page 6 and 7:
Page 8 and 9:
Page 10 and 11:
Page 12 and 13:
10An investigation into the domesti
Page 14 and 15:
Page 16 and 17:
Page 18 and 19:
Page 21 and 22: 2 Assessment of the consumer laundr
Page 23 and 24: Assessment of the consumer laundry
Page 49 and 50: Assessment of the functional perfor
Page 57: Assessment of the functional perfor
Page 71: Hygiene effects of laundry processe
Page 75 and 76: Hygiene effects of laundry processe
Page 103: Hygiene effects of laundry processe
Page 106 and 107: 104An investigation into the domest
Page 119 and 120: Appendix ASurvey of domestic laundr
Page 121 and 122: Appendix A 1199. Which temperature
Page 123 and 124:
Appendix A 1211.Working, in private
Page 125 and 126:
Appendix BDeclaration detergentsGre
Page 127 and 128:
Appendix B 125NorwayA) Omo Ultra Ta
Page 129 and 130:
Appendix CSettings of the 15°C Was
Page 131 and 132:
Appendix DSettings of the 30°C Was
show all

an investigation of domestic laundry in europe - habits ... - SIFO

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?