1. Sterilization Types & Control
Presented By –(Group 2) Dr Narendra Nath Jena, Dr Sam Raj G,
Dr Gowri Achuvath, Ms. HM Jasmine, Ms Shweta Dixit
Reviewed By-
Dr Vijay Agarwal, Dr Lallu Joseph, Dr Narayan Pendse, Dr CM Bhagat

2. Contents What is sterilization Types Steam ETO
Hydrogen Peroxide Gas Plasma
Other Methods
Monitoring the Sterilization Process
Administrative Controls
Chemical Indicator Monitoring
Biological Indicator Monitoring
Mechanical Indicators

3. What is Sterilization
Sterilization is defined as a process where all microbes are removed from a defined object, inclusive of bacterial endospores. Sterilization is needed on an everyday basis in order to promote health and eliminate the risk of contamination.

4. Types of Sterilization

5. High Temp Steam Sterilization
Steam: Dry saturated steam and entrained water (dryness fraction ≥97%)
Pressure: 15 psi serves as a means to obtain the high temperatures.
Steam-sterilizing temperatures are 121°C (250°F) and 132°C (270°F).
Time: Recognized minimum exposure periods for sterilization of wrapped healthcare supplies are 30 minutes at 121°C (250°F) & 15 psi in a gravity displacement sterilizer or 4 minutes at 132°C (270°C) & 30 psi in a prevacuum sterilizer

6. High Temp Steam Sterilization
Types Of Steam Sterilizer
Gravity,
Prevacuum,
Steam-flush Pressure-pulse or Flash
Used For:-

7. Low-Temperature Sterilization Technologies <60°C
EtO/EO – This method uses Ethylene Oxide gas to sterilize items that cannot withstand the high temperatures or humidity created using other methods.
The four essential parameters (operational ranges) are: gas concentration (450 to mg/l); temperature (37 to 63°C); relative humidity (40 to 80%)(water molecules carry ETO to reactive sites); and exposure time (1 to 6 hours).

8. Low-Temperature Sterilization Technologies <60°C
The basic ETO sterilization cycle consists of five stages (i.e., preconditioning and humidification, gas introduction, exposure, evacuation, and air washes)
ETO gas mixtures:
ETO-carbon dioxide (CO2) mixture consists of 8.5% ETO and 91.5% CO2.
ETO-hydrochlorofluorocarbons (HCFC)
100% ETO

9. 4

11. Hydrogen Peroxide Gas Plasma
Chamber is evacuated and hydrogen peroxide solution is injected from a cassette and is vaporized in the sterilization chamber to a concentration of 6 mg/l. The hydrogen peroxide vapor diffuses through the chamber (50 minutes), exposes all surfaces of the load to the sterilant, and initiates the inactivation of microorganisms. An electrical field created by a radio frequency is applied to the chamber to create a gas plasma. Microbicidal free radicals (e.g., hydroxyl and hydroperoxyl) are generated in the plasma.
Range of 37-44°c and has a cycle time of 75 minutes.

12. Other Sterilization Methods
Ionizing Radiation.
Dry-Heat Sterilizers. the static-air type and the forced-air type.
Liquid Chemicals.
Microwave.
Glass Bead “Sterilizer”.
Vaporized Hydrogen Peroxide (VHP).
Ozone.
Formaldehyde Steam. Low-temperature
Gaseous chlorine dioxide.

13. Monitoring the Sterilization Process
QAP Should include:
Administrative Controls
Chemical Indicator Monitoring
Biological Indicator Monitoring
Mechanical Indicators
Continuing Education

14. Objectives of Monitoring the Sterilization Process
Assure high probability of absence of microbes on processed items
Detect failures as soon as possible
Remove medical devices involved in failures before patient use
Improve patient outcomes
Control costs

15. Methods of Monitoring Mechanical Indicators Chemical Indicators
Equipment control
Chemical Indicators
Exposure/Process control
Pack control
Biological Indicators
Load control

16. Sterilization Process Monitors
MECHANICAL
STERILITY
ASSURANCE
COMBINED
RESULTS
CHEMICAL
BIOLOGICAL

17. Mechanical Indicators show:
what is happening in the chamber
whether conditions are being met
cycle, time, temperature and pressure
Limitations:
monitor one location in sterilizer
do not monitor each pack or tray
do not indicate sterility

18. Chemical Indicators (CI)
monitor one or more of requirements -time, temp, and sterilant
can be external and Internal
give instant results
indicate proper conditions for sterilization were present
External: distinguish between processed & unprocessed
Internal: Validates Steriliant penetration

19. Chemical Indicators

20. Biological Indicators
Confirm the ability of the sterilization process to kill microbial spores
Biological Indicators
large number of spores
Integrate all the parameters of the sterilization process
Most critical test of the sterilization process

21. Biological Indicators
Steam Sterilizer Test pack – includes BI containing Geobacillus stearothermophilus
Placement - near drain in fully loaded sterilizer
EO Test pack – includes BI containing Bacillus Subtilis
Placement - centre of normally loaded sterilizer

22. Bowie Dick Type Tests
Detects entrapped air in Vacuum- assisted sterilizers, not for Gravity
Measures steam penetration
Run daily
Test packs – can be in-house or commercially prepared

23. Bowie Dick Test Run a warm-up cycle first
Place test pack in an empty sterilizer over the drain
132C (270F) for minutes
Uniform colour change
Retain in records

24. Bowie Dick Test
Unprocessed
Processed

25. Sterilization Process Routine Monitoring
Chemical Indicator
Bowie Dick Type Test
External
Internal
CSA Recommends
Daily
Each package, tray, container

26. Sterilization Process Routine Monitoring
Biological Indicator
Steam
Flash
Ethylene Oxide
CSA Recommends
Daily; every load with an implantable device
Daily; every load with an implantable device
Every Load

27. Sterilization Process Monitors
Record Keeping
Document all materials that have been processed and the results of the sterilization process monitoring