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Safety Precautions and Operating Procedures in an (A)BSL-4 Laboratory: 2. General Practices
Published on: October 3, 2016
[Substantiation of the system of sanitary-hygienic procedures]
Abstract:
Various aspects of endogenous contamination of the human skin are discussed. The contamination rate and intensity were measured by analyzing wash water obtained after sanitary-hygienic procedures (SHP) in which no detergents were used. It was found that endogenous contamination of the human skin reached its maximum 3-4 days after the previous SHP and then became stabilized. The wash water composition was shown to be independent of the skin type. The endogenous contamination level did not influence the bactericidal effect of the skin of healthy people. Due to complementary processes such as epidermis desquamation and sebum cutaneum, the role of which is different for different skin types, the amount of indigenous microorganisms is maintained at an optimal level irrespective of the skin type. It is concluded that water SHPs should be performed no more than once every four days. If they are conducted oftener than that, the normal function of the human skin may become deteriorated: epidermis desquamation increases drastically, skin state changes, and the concentration of indigenous microorganisms on the skin surface decreases as compared to the individual norm.
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