DISINFECTION & STERLIZATION

Disinfection
Disinfection is the elimination of pathogens, except spores, from inanimate objects
Disinfectants are chemical solutions used to clean inanimate objects
(physical processes, e.g., UV radiation, may also be employed to effect disinfection)
Germicides are chemicals that can be applied to both animate (living) and inanimate objects for the purpose of eliminating pathogens
Antiseptics are formulated for application to living tissue
The Ideal Disinfectant
Resistant to inactviation
Broadly active (killing pathogens)
Not poisonous (or otherwise harmful)
Penetrating (to pathogens)
Not damaging to non-living materials
Stable
Easy to work with
Otherwise not unpleasant
Sterilization
Sterilization is the total elimination of all microorganisms including spores
Typically the last things to die are the highly heat- and chemical-resistant bacterial endospores
Instruments used for invasive procedures must be sterilized prior to use
Moist heat or steam, radiation, chemicals (e.g., glutaraldehyde), and ethylene oxide (a gas) are employed for sterilization
Sterilization by autoclaving, which uses moist heat, is used in most hospital and microbiology laboratory settings
Sterilization Times
171o C, 60 minutes, dry heat
160o C, 120 minutes, dry heat
149o C, 150 minutes, dry heat
141o C, 180 minutes, dry heat
121o C, 12 hours, dry heat
121o C, 15 minutes, moist heat (but don’t start the clock until entire item is up to temp—e.g., large volumes fluid)