CHAPTER XI. 



PRACTICAL STERILIZATION, ANTISEPSIS AND 

 DISINFECTION. 



LABORATORY STERILIZATION. 

 Physical Agents. 



Heat. 



Live Steam. 



Fractional Sterilization. 



Boiling Water. 

 Chemical Solutions. 



Salts of Heavy Metals. 



Oxidizing Solutions. 



Phenols, Cresols. 



Tincture of lodin. 



Boric Acid. 



Formaldehyde. 



Essential Oils. 



Testing and Standardizing 

 Disinfectants. 



Liquid 



Gaseous Disinfectants. 

 Formaldehyde. 

 Paraform. 

 Sulphur. 

 Chlorine Gas. 

 Ozone. 

 PRACTICAL DISINFECTION. 



Sputum. 



Vomitus. 



Feces and Urine. 



Fomites. 



Bath Water. 



Skin and Hand. 



Instruments. 



Clinical Thermometers Dental Instru- 

 ments. 



THE terms sterilization, disinfection, antisepsis and deodorization 

 are frequently used indiscriminately, but it is important to distinguish 

 between them. Sterilization and disinfection imply the destruction 

 of microorganisms, the latter being restricted largely to hygienic 

 procedure, as the disinfection of excreta, etc. A restriction of bac- 

 terial growth not necessarily involving the death of microorganisms 

 is properly termed antisepsis. Deodorants, as the term signifies, are 

 those substances which destroy or mask odors; deodorants may or 

 may not destroy bacteria. 



LABORATORY STERILIZATION. 



The many kinds of apparatus and media used in the study of bac- 

 teria must be freed from adventitious organisms before they are 

 applicable to bacteriological investigation. Physical and chemical 

 agents are commonly made use of for this purpose. 



Physical Agents. 1. Heat. (a) Incineration. Incineration ,is a 

 most efficient method of sterilizing articles of little value. The free 

 flame is commonly used for sterilizing platinum needles and platinum 

 loops. If the latter are charged with pathogenic bacteria, and par- 

 ticularly bacteria which contain fats, as the tubercle bacillus, it is 



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