Section 4 Sterilization Process
Safety in Sterilization for H202 Sterilizers
Damaged containers may release sterilant, items in an aborted cycle may contain trace amount , which can cause a chemical burn to unprotected hands and skin. Disposals should be handled with gloves
Loading Hydrogen peroxide gas plasma
If the available amount of h202 is reduced because it reacts or is absorbed before reaching all surfaces a sterilization failure can accrue of over loaded
Ethylene oxide internal indicators recommendations
Internal used in the inside package each package to measure whether the sterilant has penetrated the package
What is a process challenge device
Is designed to challenge a sterilization cycle and commericially prepared. May contain a CI or a CI and BI
Hydrogen peroxide gas plasma physical monitoring recommendations
Operate on a fixed automatic cycle controlled by microprocessors. All critical parameters are monitored during the operation of the cycle
hydrogen peroxide (H2O2) gas and vaporized biological indicator recommendation
Performed at least daily but preferably with each load using Geobacillus stearothermophilus
How to make your own PCD for table top steam sterilizers
Pick a tray of Instruments or package that represents the most difficult item to be sterilized. Use this every time. Place a BI & CI in the most challenging area in the pack.
Table Top Sterilizers operation
Poet at the bottom are heated electricity until turned to steam, steam rises , cool air is forced out thru the drain , a thermostatic valve closes for steam to build up pressure until temp is reached , timer gets activated, at the end the relief valve opens, steam leaves. Steam goes thru the water reservoir back to water. Pressure goes to 0 the door opens
Multiple Cycle Testing
Some dynamic air removal and IUSS can use either dynamic air removal or gravity mode. These you have to do a BI & PCD at least weekly preferably daily in both modes
Gravity Air Displacement Sterilizers operation
Steam enters the chamber and because air is denser then steam it forces the air to the bottom and out the drain. They have physical monitoring like temp charts and print outs
Action Level / AL-Exposure Limits- (0.5 ppm / 8 hours);
These levels are established to ensure adequate protection of employees at exposures below the OSHA limits, but to minimize the compliance burdens for employers whose employees have exposures below the 8 hour permissible exposure limit (PEL) The AL for formaldehyde is 0.5 ppm.
Testing Dynamic Air Removal Sterilizers Bowie Dick Test
Use Bowie dick test which is a class II CI tests effectiveness of the steam sterilizer to remove air from the chamber. Performed each day sterilizer is in use. Only have carriage to hold test and the test itself in the sterilizer and placed over the chamber drain and run per MIFU. If color change is not uniform it's a fail
Loading of vaporized hydrogen peroxide sterilizer
Use only approved devices Follow weight limit Use only approved package types Follow MIFU for lumen size, length and quantity
Hydrogen peroxide gas plasma & vaporized external indicator recommendations
Used on Every package to demonstrate exposure to hydrogen peroxide gas plasma
Ethylene oxide external & internal indicators recommendations
Used on every package outside to demonstrate each package has been processed.
Testing Dynamic Air Removal Sterilizers Leak Test
Used to ensure there are no leaks with in the chamber tests the sterilizer ability to hold a vacuum by testing all the sealed areas and piping to ensure air is not allowed into the chamber during the vacuum phase. Done weekly
Biological monitoring in Immediate use steam sterilizer ( IUSS)
Weekly, preferred each day in use and with every load.
EO workspace
Well ventilation air exchange rate 10 per hr , negative pressure rooms with ventilation system, exhaust lines and floor drains. Cartridges stored in ventilated flammable liquid storage cabinet that is exhausted outside away from flammables
When to use a Process Challenge device
With every implant needs PCD they have a BI and class V CI , steam sterilizers and gravity using single use ones, immediate use sterilizers only use BI no PCD, no commercially prepared ones for tabletop steam sterilizers, EO in every load, H202 only made for some models run at least daily preferred each load
Load control (LOT) number
label information on sterilization packages, trays, or containers that identifies the sterilizer, cycle run, and date of sterilization
Safety in Sterilization for EO Sterilizers
osha established in 1984 1ppm in air PEL and a .05 ppm action level Includes negative pressure airflow to prevent exposure if malfunction and auto lockdown until aeration cycle is complete Performed in separate area, must have ventilation system should be checked regularly, and have an audible alarm. EO Canisters stored in approved containment locker. Use local regs for allowed amount of canisters Report exposures to Sp manager , employee health nurse and service and emergency department Must comply with federal, state and local air regulations for safety, discharge, air monitoring, records
Unloading sterilizers
1. Open the sterilizer door according o protocol. 2. Load should be free from ANY VISIBLE LIQUID 3. Anything wet is considered contaminated. 4. Don't touch anything that has just come out 5. Don't handle until cool (usually 30-60 minutes) to room temp. can using temp devices Place load in low traffic , no air conditioning or cold air vents Handle as little as possible
Short Term Exposure Limit (STEL)
15 - minute Time Weighted Average (TWA) exposure that should no be exceeded during a typical work day.
Hydrogen peroxide gas plasma operation
28-38 mins 75 cycle times Phases: Vacuum- heated while the vacuum removes air from chamber and items until pressure is reduced to below atmospheric pressure Injection- enters h202 Diffusion - put h2o2 into small crevices and lumens devices Plasma - vacuum decreases pressure, radio frequency energy is radiated from electrode screen, then crests H202 gas plasma and repeated twice Vent - air enters HEPA filters returning the chamber to atmospheric pressure. Byproducts are air and vapor , aeration is not required instruments can be used immediately after cooled
Vaporized Hydrogen peroxide operation
55 mins or 28 mins used to process heat sensitive devices. VHP is injected not a vaporized chamber to be heated and changed to vapor and put into the chamber under neg pressure. Uses to inject by a cup or an ample in a cassette Conditioning - chamber is evacuated to remove air and moisture then recharged with dry filtered air Leak test- vacuum is held to ensure a leak tight chamber Sterilization -injects VHP with a series of pulses each followed by a hold period Aeration- VHP is exhausted through a catalytic converter to change it to water and oxygen, no venting needed
Steam sterilizer cycles
Conditioning- Steam enters upper chamber, air is displaced, thru drain as steam enters pressure risers and so does the temp Exposure- once temp is reached timer starts Exhaust-chamber is opened steam leaves thru discharge line, void is created , filtered air comes in, returns to room pressure Dry-end of dry cycle signal sounds door opens
Loading Steam Sterilizers
Don't overload, position instruments to allow steam circulation, air to exit and steam to enter and drying, visible space, place hard goods like rigid containers on the bottom, packs don't touch walls, basins on edge, Peel pouch on edge Placed wrapped items at a 90 angle perpendicular to the shelf Try to sterilize wrapped( textiles) and ridged containers( hard goods) in separate loads if not place textiles on top and hard in bottom Of shelf liner is used it can't be absorbent Instrument trays are perforated bottoms Rigid containers sit flat
Cleaning sterilizers
Drain strainer to be removed and cleaned daily or more if needed under running water, door gasket inspected and wiped clean daily with damp non lint cloth , carriages, carts, loading baskets, cleaned routinely with mild solution, follow MIFU for cleaning and lubrication, Follow MIFU for chamber cleaning and draining Chamber needs to be cooled Inside the chamber should be cleaned per MIFU and rinsed using detergent and non lint towel Inspect records daily Don't use abrasives or steel wool
What is an external indicator
It's the first performance test the user sees when removing a package from the sterilizer. They provide instant results and visual evidence the package was exposed to the sterilant.
Load log sheet documentation
Loaf control ( lot) number , so sterilizer identification, cycle number, date and time sterilized, specific items sterilized including quantity and department and item description, exposure time and temp . Sterilizer operator ID, results of biological ( if applicable)
When to use a self made PCD in table top sterilizer
Major repair do three consecutive tests cycles and results read before put into use
Ethylene oxide physical monitor recommendations
Monitor pressure gauges , temp control/ measurement devices, timing records and humidity sensors
Hydrogen peroxide vaporized physical monitoring recommendations
Monitoring all critical parameters during the operation of the cycle
Tabletop Steam Sterilizer Testing
No commercial PCD made but you can create your own.
Loading EO sterilizers
No overloading, no contact with walls , pouches placed on edge, no stacking of instruments, only up in full loads that share common aeration times, if not full load much better documented kept for 5 yrs , recent two yrs onsite
IUSS documentation should include
Pt. Id , date and time , sterilizer id, cycle temp and time, items, required, reason, CI results, BI results of appropriate.
Ethylene oxide biological indicator recommendations
Required for each cycle using Bacillus atrophaeus follow MIFU for placement and incubation
Biological indicator testing recommendations
Run weekly but preferably every day that the sterilizer is in use and with every implant device. Some will choose to do with every load
Steam Flush Pressure Pulse Sterilizers operation
SFPP uses a repeat sequence of steam flush and pressure to remove air from chamber and processed material rapidly. Air removal occurred above Atmospheric pressure no vacuum is needed
Hydrogen peroxide gas plasma & vaporized internal indicator recommendations
Should be used to demonstrate exposure exposure to hydrogen peroxide and placed at a challenging location in the pack
Dynamic Air Removal Sterilizers operation
Similar construction to gravity air except there is a vacuum pump or water ejector that removes air more efficiently during preconditioning phase prior to reaching temp. This speeds up the cycle and reduce air pockets. 132-135 270 to 275. They use different methods of air removal like the steam flush pressure pulse sterilizers. It removes air from the chamber and load before chamber is pressurized with steam to reach temp
BI, PCD and Bowie Dicks test should so be preformed when
Sterilizers gets repairs, construction, malfunction, and routine per MIFUS
Examples of external indicators
Tape, load cards, labels, external color change on peel pouches
Prevacuum Steam Sterilizers operation
The dynamic air removal cycle depends on one or more pressure and vacuum sequences at the 1st of the cycle to remove air during preconditioning phase. Needs checked daily by Bowie dick test. Leak test also preformed to check vacuum tightening of chamber 132-135 270 to 275
Ethylene oxide Sterilizers operation
The gas is provided in single dose cartridges placed inside the chamber of it leaks the ventilation will pull room air into the system Five stages preconditioned, humidification, gas intro, exposure, evacuation, air wash. Take 2 1/2 to 3/12 excluding aeration time. Once done it's goes through aeration to remove all EO before unlocked
