Autoclave Operation

Proc. #

Autoclave Operation

Author: Peggy Coulter / Document Number: / Fac20-02
Effective (or Post) Date: / 17 February 2009
Document Origin / Company: / JHH
SMILE Approved by: / Peggy Coulter
SMILE Comments: This document is provided as an example only. It must be revised to accurately reflect your lab’s specific processes and/or specific protocol requirements. Users are directed to counter check facts when considering their use in other applications. If you have any questions contact SMILE.
Procedure: Autoclave (Steam Sterilizer) Operation

Initial Review and Approval Date: 10/30/2003

Assistant Administrator
Technical Supervisor
Technical Supervisor
Prepared By / Peggy Coulter / 9/16/2003
Director
Director
Director
Adopted: / Retired:
Reviewed: / Replaces: New / Date: 9/16/2003
Procedure Locations
General Operating Procedures
Authorized to Approve: Medical Director
Authorized to Review:

PERSONAL PROTECTIVE EQUIPMENT

Performance of this procedure will expose testing personnel to biohazardous material and possible chemical hazards.
All specimens must be handled as potentially infectious material as outlined in the (your lab) Safety Manual.
The reagent(s) and/or chemical(s), which are used in this assay, may be hazardous to your health if handled incorrectly. A brief listing of precautions for each chemical hazard is included in the reagent section of this procedure.
More extensive information concerning the safe handling of the reagents and/or chemicals used in this assay, as well as other important safety information, may be obtained by consulting the Material Safety Data Sheet (MSDS) and HAZ-COM Manual, and (your lab) safety manual. Before performing any part of this assay, the technologist must take any and all precautions and adhere to all prescribed policies.
This procedure may expose you to:
[X] Bloodborne pathogens
[X] Airborne pathogens
[X] Hazardous reagents
To perform this procedure, you must use:
[X] Gloves
[ ] Face shield, or safety glasses with mask
[X] Laboratory coat
[ ] Gown
[ ] Biological safety cabinet
[ ] Fume hood
[ ] Ventilator
[ ] Disinfectant following procedure:
[ ] Diluted bleach (1:10v/v solution made fresh daily)
[ ] Amphyl
[ ] Caltech Dispatch with Bleach
[ ] Miscellaneous, after Hospital Infection Control Department approval
Reference for spill/decontamination:
[ ] MSDS
[X] Chemical hygiene plan


PRINCIPLE:

Heat kills microorganisms by denaturing their enzymes and structural proteins. Time to death is dependent on heat resistance of the organism and conditions of sterilization. Thermal death occurs more quickly in saturated steam than in dry heat because the temperature at which denaturation of proteins occurs is inversely proportional to the amount of moisture present. Pressure in the chamber facilitates control of the temperature at which boiling water turns to steam; the higher the pressure, the higher the temperature must be before the water becomes vaporized. The higher the temperature, the shorter the sterilization cycle needed to achieve acceptable killing levels.

An autoclave is an instrument for decontamination of heat-stable materials by physical means. The sealed chamber allows conditions of heat, pressure, and atmosphere to be created and held for optimal time of exposure needed to achieve sterilization of biological agents.

Autoclaves are used in the Microbiology laboratory to sterilize clean, wrapped instruments and containers, to sterilize media, and to render microbiologically contaminated materials biologically safe (sterile) before they are discarded. This does not affect radioactivity or chemical toxicity of autoclaved materials.

A.  Steps in operation

1.  Air in chamber is replaced by steam running through valves with gaskets. Air must be replaced by steam throughout the entire autoclave load for effective sterilization to occur. Air is denser and cooler than steam, so it flows down the drain during the steam intake cycle.

2.  Pressure is increased, and temperature rises.

3.  Sterilization starts when preset temperature and pressure are reached.

4.  Cooling cycle follows release of steam.

B.  Cycles

1.  Many instruments have automated cycle selection to standardized sterilization conditions.

2. Cycles are based on the nature of the material being autoclaved.

a. Liquid

Slow exhaust prevents boiling over of hot liquids as the chamber pressure drops.

b. Dry, unwrapped

Fast exhaust and no drying time

c. Dry, wrapped

Fast exhaust and extended period of dry heat to remove moisture from wrappings or from inside empty tubes or glass containers

d. Melting agar in tubes or flasks

Short, 3-min heating cycle for melting agar and relatively slow exhaust

SPECIMEN:

A. Contaminated Materials- Follow S.O.P. for Disposal of Waste

1. Autoclave Buckets with Microbiological waste in red bags

2. Sharps containers – Red

3. Sharps containers – metal trays

B. Media to be sterilized- Follow S.O.P. for Media

1. Flasks of prepared media

2. Tubed media

EQUIPMENT AND MATERIALS:

Equipment:

1.  Autoclaves in room B1-112

-used for media preparation and equipment sterilization only.

2.  Autoclaves in room B1-118

-used for decontamination only.

Materials:

Temperature Chart

QUALITY CONTROL:

Steris Verify Steam Test Pack is used to monitor sterilization weekly following the Autoclave Quality Control S.O.P.

PROCEDURE – STEPWISE:

A.  Before Operating The Equipment:

1.  Be sure that chamber drain strainer is clean and in place and that the chamber interior is clean.

2.  Open the upper access door. (See Appendix A) Turn STEAM and WATER valves to ON.

3.  Open the door to the secondary control panel, and position the POWER and CONTROL switches to ON. The primary control panel lights up.

4.  Position GRAVITY/ISO switch to desired function. GRAVITY for Gravity or Liquids cycle; ISO for Laboratory/Isothermal cycle. (Refer to Appendix B for setting choices.)

B.  AUTOMATIC OPERATION FOR ALL CYCLES:

1.  Open the upper access door and turn HI-LO valve to HI for the 270˚ F(132˚ C) sterilizing cycle, or to LO for the 250˚ F(121˚ C) sterilizing cycle.

2.  Open the door on the secondary control panel.

a.  Be sure POWER and CONTROL switches are ON. Primary control panel should be lit.

b.  Dial the correct exposure period on STERILIZE TIME thumbwheel switches.

c.  Dial the desired drying period on DRY TIME thumbwheel switches.

  1. For wrapped goods- 15 minutes recommended
  2. For unwrapped goods- drying time not required, however a minimum of 02 minutes will eliminate excess steam vapors prior to opening chamber door.
  3. For liquids- controller automatically disregards any DRY time setting and blanks out that portion of the display.

3.  Install a new paper chart on the Indicator-Recorder-Controller at the beginning of each day.

4.  Set the yellow pointer on the indicator-recorder-controller to 270˚ F (132˚ C) or to 250˚ F (121˚ C).

5.  Open chamber door and load sterilizer.

Turn handwheel counterclockwise. If the door does not at first unlock, turn door wheel slightly clockwise, press the center black button, then again turn door wheel counterclockwise and open.

6.  Close and lock the door. Panel light DOOR UNLOCKED must go off. Once chamber is pressurized, a pressure-actuated lock will prevent door from being opened. Turn handwheel to the right as far as it will go using normal hand pressure.

7.  Continue with appropriate cycle instructions.

C.  GRAVITY CYCLE:

1.  Touch GRAVITY cycle selector. Light comes on to full brightness. Status light CONDITION comes on.

2.  After condition phase is completed, STERILIZE light comes on and stays on for the Sterilize phase. STERILIZE TIME readout begins to count down when sterilizing temperature is reached.

3.  When sterilize timer times out, EXHAUST light comes on. Chamber exhausts to atmospheric pressure. If a drying period was selected, DRY TIME readout begins to count down.

4.  When exhaust phase is completed, panel light COMPLETE comes on and buzzer sounds. Open chamber door, load may be removed from the sterilizer, wearing heat resistant gloves.

D.  LIQUID CYCLE:

1.  Touch LIQUIDS cycle selector. . Light comes on to full brightness. Status light CONDITION comes on; also WARNING HOT LIQUIDS light comes on.

2.  After condition phase is completed, STERILIZE light comes on and stays on for the Sterilize phase. STERILIZE TIME readout begins to count down when sterilizing temperature is reached.

3.  When sterilize timer times out, EXHAUST light comes on and chamber exhausts slowly.

4.  When exhaust phase is completed, panel light COMPLETE comes on and buzzer sounds. Open chamber door, load may be removed from the sterilizer.

5.  Crack the door open about ½ “ and leave it cracked for at least 10 minutes.

6.  Unlocking the door will stop buzzer and cause DOOR UNLOCKED light to come on. WARNING HOT LIQUIDS light will remain on, but will begin to flash for 10 minutes. At the end of 10 minutes, buzzer will again sound and WARNING HOT LIQUIDS light will stay on, but will stop flashing.

7.  Open chamber door, load may now be removed from sterilizer, using heat resistant gloves. Press RESET button on secondary control panel to reset control and turn warning light off.

E.  LABORATORY/ISOTHERMAL CYCLE:

1.  Touch ISOTHERMAL cycle selector. Light comes on to full brightness. Status light CONDITION comes on.

2.  After condition phase is completed, STERILIZE light comes on and stays on for the Sterilize phase. STERILIZE TIME readout begins to count down when sterilizing temperature is reached.

3.  When sterilize timer times out, EXHAUST light comes on and chamber exhausts slowly.

4.  When exhaust phase is completed, panel light COMPLETE comes on and buzzer sounds. Open chamber door, load may be removed from the sterilizer, using heat resistant gloves.

Procedures for Abnormal Results:

a.  Use the troubleshooting chart (Appendix B), to identify the problem and probable cause.

b.  If you are unable to correct the problem with the use of the chart, or if a problem occurs not described on the chart, notify a Supervisor or Lead Technologist who may call for service.

REFERENCES:

1.  ASM Clinical Microbiology Procedures, Washington, DC, 1992, pg12.3.1

2.  AMSCO Laboratory/Isothermal Sterilizer Equipment Manual, 1980.

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