Steam Flashcards
Why do we use steam
it carries a massive amount of energy
it is a non toxic component in the sterilization process
for certain applications it can be recondensed and used again
the main ingredient is water which is readily available
there is no waste product except water
the volume of steam is greater than water which creates a huge amount of pressure within small confined spaces and this high pressure helps with the permeability of steam
What is essential for the production of steam
purified water
Why must we use purified water
as it has organs, minerals and bacterial presence removed
What are the 3 types of sterilizers available
type N
type B
type S
What is type N
more common
most basic process of the sterilizers also referred to as the gravity displacement sterilizer
What is type B
this has the most robust processing cycle of all the equipment
also referred to as a vacuum capable or porous load sterilizer
What is type S
this machine is generally a specialized piece of equipment, used for a specific purpose e.g sterilizing dental hand pieces
How does type N work
this machine heats water in the chamber as it turns to steam passively forces the air from the chamber
this process isn’t entirely efficient and can leave pockets of air within the chamber
this is not favorable for high quality sterilization process and means that we cannot process wrapped instruments or channeled or lumped instruments ether
How does air differ from steam
it cannot be heated or maintain temperature the same way heat can
it is always a lower temp than the steam surrounding it
if it is contact with air it is not contacting steam and this means anything that the air is in contact with may not achieve its sterilization temp for the minimum required time
What instruments should be processed in a type N sterilizer
as the cycle isn’t entirely efficient it is recommended that we only process rigid steel instruments with no pockets, channels or lumens
What instruments should not be processed in a type N sterilizer
wrapped instrumentation
What temp must the type N sterilizer reach
134-137 degrees for minimum stage hold time of 3 mins
after this it has been sterilized and it may not be sterile at the point of use
What is a type B sterilizer
the first step on this machine to remove all the air from the chamber using a vacuum pump and after that it fills the chamber with steam that it has generated for the process
because the air has been removed first, a vacuum has been created and this allows the steam to rush into the chamber meaning that it effectively contacts all surfaces of what it is being processed
it even has the capability to penetrate the wrappings of instrumentations and sterilize them through wrappings
What instruments can be processed in a type B sterilizer
wrapped, channeled and lumened instruments
we can also process porous items such as cotton wool swabs
How does the type B sterilizer work
it starts by removing all the air from the chamber creating a negative pressure
as the steam rushes in, it expands into the chamber and is forced to contact all surfaces due to the vacuum effect, penetrating wrappings as well
it must achieve the same temp fo 134-137 degrees celsius and hold this for the same stage time of 3 minutes
it then has a drying stage at the end to remove any remaining moisture
