Sterilization,disinfection and antisepsis ,session 1
PRACTICAL SESSION: 1
COURSE: PRINCIPLES OF DISEASE I
LEVEL 4 MEDICINE
Dr. DOHA SIJA
Dr. EIMAN ELNAKEEB
Dr. HESHAM AZIZ
Dr. MOHAMED RAOUF
Dr. RIM MOHAMED
To discuss the difference between
sterilization , disinfection and antiseptics
and the methods to use each of these .
The effective decontamination of spillage,
surfaces and equipment after use.
►Advice on adequacy of sterilization and
disinfection procedure used in surgical and
Microorganisms are the agents of
Hence it becomes necessary to remove
them from materials and areas.
Is the Complete destruction and killing of all
microbes, including endospores.
Can be achieved by mechanical means, heat ,
chemicals or radiation.
The common types of sterilization : heat
Heat methods of sterilization
Kills microorganisms by denaturing their
enzymes and other proteins. Heat
resistance varies widely among microbes.
fast, reliable, inexpensive
or Wire, the tip of
spatulas are held
in a bunsen flame
till they are red
B)Hot Air Oven
Place objects in an
oven (from 50oC to
300oC) . Require
between 90 and
120 minutes at
►To sterilize Forceps, Scissors, Scalpels, Swabs.
►Pharmaceuticals products like Liquid paraffin, dusting
powder, fats and grease.
►At temperature below 100°C:
Pasteurization: there are two methods of
pasteurization, the holder method (heated
at 63°C for 30 minutes) and flash method
(heated at 72°C for 15 seconds) followed by
quickly cooling to 13°C.
►At a temperature 100°C:
Boiling: (100°C) for 10-30 minutes kills most
vegetative bacteria and viruses immediately.
Some bacterial spores are resistant to
Boiling and survive
2. Moist Heat
At a temperature above
Autoclave: Chamber which
is filled with hot steam under
pressure. Preferred method
of sterilization, unless
material is damaged by heat,
moisture, or high pressure.
Temperature of steam
reaches 120oC at twice
All organisms and
endospores are killed
within 15 minutes.
►ETHYLENE OXIDE GAS
ITEMS THAT ARE SENSITIVE HEAT/ MOISTURE.
STERILIZATION IS ACHIEVED THROUGH LOW -
►HYDROGEN PEROXIDE PLASMA VAPOR
SAFE AND NON-TOXIC
►Is the process of eliminates most or all
microorganisms, with the exception of
Endospores (Reducing the number of
pathogenic microorganisms to the point
where they no longer cause infection)
►Disinfectant: An agent applied to
Kills all microbes
Some Viruses and
Exposure less than
Disinfection of hands :
** Alcohol-based rubs.
is the process of destroying or
inhibiting the growth of microorganisms on
the living tissue.
►Chemicals used to kill microorganisms on
the surface of skin and mucous membranes.
►A substance applied on a living tissue.
An agent that kills bacteria. Most do not kill
An agent that inhibits the growth of
bacteria, but does not necessarily kill them.
An agent that kills certain
►Bactericide: An agent that kills
bacteria. Most do not kill endospores.
►Viricide: An agent that inactivates
►Fungicide: An agent that kills fungi.
►Sporicide: An agent that kills bacterial
endospores of fungal spores.
►Degerming: Removal of most
microbes in a limited area. Example:
Alcohol swab on skin.
►Sanitization: Use of chemical agent
on food-handling equipment to meet
public health standards and minimize
chances of disease transmission. e.g.:
Hot soap & water