Laundries that use proper laundering techniques can assure their customers that the textiles are hygienically clean. Within our industry, there is no universally accepted definition of “hygienically clean.” However, it usually means the textiles have been treated to a point where the biological contaminants (bioburden) have been removed and the item can be used without fear or risk of being a source of contamination in a healthcare use. AAMI (Association for the Advancement of Medical Instrumentation) defines the term "hygienically clean" as "free of pathogens in sufficient numbers to cause human illness."
In a laundry, the wash process utilizes several techniques to assure the bioburden is reduced or eliminated:
Dilution: Several water changes during the cleaning process physically remove and flush away bio-organisms. Mechanical action is also a factor to consider as bioburden is loosened from the fabric by proper mechanical action.
Heat: Washing at elevated temperatures (>160ºF) deactivates most of the common bio-organisms; however studies also show microbial reductions can be achieved at temperatures as low as 72ºF.
pH: High pH (>10.5) will "attack" or deactivate bio-organisms. In addition, large swings in pH, from neutral (7.0 - 8.0) in first flushes, to alkaline (10.5 - 11.5) during the main wash cycles, to acidic (5.5 - 6.5) in the final rinse, will adversely affect bio-organisms.
Oxidation: Chlorine bleach or oxygen bleaches contribute to bio-organism deactivation. Chlorine bleaches are well known to have excellent anti-bacterial and anti-viral efficacy. Oxygen bleach is considered to be somewhat less aggressive on bacteria and viruses, however, when combined with the other cleaning factors in a laundry formula, oxygen bleach is considered effective in deactivating residual microbes.
Chemical Sanitizers or Bacteriostats: Some laundries as an extra precaution will use EPA registered products that will act as sanitizers in the final step of the laundry process.
Drying/Ironing: Drying or ironing at temperatures that exceed 180ºF on the fabric surface deactivate any potential remaining organisms.
The CDC (Centers for Disease Control and Prevention) indicates that a well designed wash formula that appropriately uses the above techniques will provide “hygienically clean” textiles.
Laundries that use proper laundering techniques can assure their customers that the textiles are hygienically clean. Within our industry, there is no universally accepted definition of “hygienically clean.” However, it usually means the textiles have been treated to a point where the biological contaminants (bioburden) have been removed and the item can be used without fear or risk of being a source of contamination in a healthcare use. AAMI (Association for the Advancement of Medical Instrumentation) defines the term "hygienically clean" as "free of pathogens in sufficient numbers to cause human illness."
Dilution: Several water changes during the cleaning process physically remove and flush away bio-organisms. Mechanical action is also a factor to consider as bioburden is loosened from the fabric by proper mechanical action.