2. Objectives:Objectives:
As a result of successfully completing this
chapter, students will be able to:
Discuss basic requirements important for any
type of low temperature sterilization system
Explain specific requirements for the three low
temperature sterilization methods: ethylene
oxide, hydrogen peroxide (gas plasma), and
ozone
Review (compare) important parameters of the
three low temperature sterilization methods
commonly used by health care facilities
6. Ethylene Oxide ProcessEthylene Oxide Process
ParametersParameters
Time
Temperature
Concentration of
EtO
Relative Humidity
7. TerminologyTerminology
Residual- The amount of EtO that remains inside of materials
after they have been sterilized
Aeration- A process in which a device is actively subjected to
moving air. For example, items that have been sterilized with
EtO
Sterility Assurance Level (SAL)- The probability of a viable
microorganism being present on a product after sterilization
Permissible Exposure Limits (PELs)- Limits developed by
OSHA to indicate the maximum concentration of a contaminant
to which an employee may be exposed over the duration
assigned to that contaminant
Time Weighted Average (TWA)- The employee’s average
airborne exposure in any 8-hour work shift of a 40 hour work
week
Parts Per Million (PPM)- Parts Per Million (PPM) is the term
used to measure the volume of gas in a vapor
9. Employee SafetyEmployee Safety
Employees should receive instruction on:
◦ Hazards of EtO
◦ Procedures to reduce employee exposure
◦ Principles of EtO monitoring and interpretation of results
◦ Use of protective equipment
◦ OSHA Standards
◦ MSDS Sheets
◦ EtO Emergency Plans
◦ Processing procedures
◦ Storage and handling of EtO gas containers
10. EtO SafetyEtO Safety
EtO is a Toxic Gas
EtO Sterilizers should be located in a well-
ventilated area with a room air exchange rate of
10 air exchanges per hour
Additional information about EtO safety is
included in Chapter 21, Safety, pages 405 – 408
of the text
11. Personnel MonitoringPersonnel Monitoring
Personal devices worn with
1 foot of the employee’s
breathing zone
◦ Provide delayed results
Area monitors
continuously monitor
airborne EtO
◦ Provide real-time information
12. Education Should also include:Education Should also include:
Specific training
from the
manufacturers of
the gas
containers and
the sterilizer
13. Aeration of EtO SterilizedAeration of EtO Sterilized
ItemsItems
Minimum recommendations for aeration:
◦ 8 hours at 1400
F (600
C)
◦ 12 hours at 1220
F (500
C)
*Some items require significantly longer
aeration. Consult device manufacturer’s
recommendations for specific guidelines
14. Loading the EtO SterilizerLoading the EtO Sterilizer
Do not overload
When possible use metal carts
or baskets
Do not let items come in
contact with chamber walls
Place peel pouches on edge
Do not stack items on top of
one another
15. Unloading the EtO SterilizerUnloading the EtO Sterilizer
If possible aerate before
handling
When transferring loads to
the aerator, pull, don’t push
the load
Follow your specific
facility's safety protocols
Once a load has been
placed in the aerator, new
groups of sterilized items
should not be added
16. EtO Sterilizer PerformanceEtO Sterilizer Performance
MonitorsMonitors
Physical Monitors (Charts, Printout Tapes
and Graphs
Chemical Indicators
Biological Indicators (Bacillus atrophaeus)
17. Hydrogen Peroxide (Gas Plasma)Hydrogen Peroxide (Gas Plasma)
Popular because of its short cycle
times
Uses H2O2 vapor and low
temperature gas plasma doe rapid
inactivation of microorganisms
Is widely compatible with different
materials
Is not compatible with powders
and strong absorbers like paper
and linen made of cellulose
There are some restrictions
regarding the sterilization of
lumens (diameter and length).
Consult device manufacturer
recommendations for specific
parameters
18. Staff Safety Education:Staff Safety Education:
Hazards of H2O2
MSDS Sheets
OSHA PEL
Process for changing vapor plates
Storage, handling and disposal of
cassettes
20. OzoneOzone
Newest low temperature
process
No purchase of sterilant
needed. The system
generates the O3 needed
Process parameters:
◦ Time
◦ Temperature
◦ O3 Concentration
◦ Relative Humidity
21. Overview of LowOverview of Low
Temperature ProcessesTemperature Processes
A comparison
chart of the low
temperature
sterilization
methods covered
in this unit is
located on page
341 of the text.