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Tips to Assure Effective Sterilization by Autoclave

Failure to effectively sterilize an autoclave load can be due to either a mechanical problem with the equipment or operator error. Report mechanical problems to FM. Operator errors are generally due to insufficient steam circulation and penetration due to:

Note: Do Not autoclave plastic unless it is rated as autoclavable. Do not exceed the temperature that the material is rated for. Melted plastic releases fumes, ruins autoclave surfaces and can clog chamber drains.

Trouble Shooting Problems

Problem Cause Corrections
Clogged Drain Agar boiled over or other debris. Clean chamber drain strainer, if still clogged call FM.
Wet Wrappers -Overloaded baskets or racks -Load loosely
-Clogged chamber drain strainer not allowing water to drain -Remove strainer; free openings of lints, sediment, etc.
-Clogged chamber drain line. -Clean chamber drain line; mix 2 tbsp. trisodium phosphate with one quart of hot water, pour into chamber drain line. Then flush drain with one quart of hot tap water. If still clogged call FM.
-Excessively large or dense packs. -Reduce pack to 12" x 12" x 20" or less; and 12 pounds or less.
-Placing warm sterilized packs on cold surfaces -Allow packs to cool on rack or in autoclave
-Sterilized goods removed from sterilizer too soon following completion of cycle. -Allow goods to remain in autoclave additional 15 minutes with door slightly open.
Improper loading -Place packs on edge; arrange packs to present the least possible resistance to passage of steam and air through layers of load
-Combining items in a pack -Wrap separately.
Corroded Instruments -Poor cleaning: residual soil -Improve cleaning. Do not allow soil to dry on instruments
-Moisture. -Check sterilizer for drying efficiency. Store in a dry area
-Exposure to harsh chemicals: acids, iodine, sodium chloride, detergents, etc -Do not expose instruments to these chemicals. If exposure occurs, rinse thoroughly after contact
-Inferior instruments -Use only top-quality instruments
-Metallic deposition resulting from galvanic reaction with sterilizer components -Keep sterilizer chamber and trays clean. Use detergent recommended by manufacturer
Caps "Blow off" of Liquid Containers -Exhausting sterilizer too rapidly. -Use slow exhaust cycle.
-Maladjusted slow exhaust valve -Notify FM
Loss of More than 5% Fluid Volume during Sterilization -Exhausting sterilizer too rapidly. -Use slow exhaust cycle
-Maladjusted slow exhaust valve. -Notify FM
Cracked or Broken glass Containers -Cracked before sterilization; poor inspection following cleaning. -Inspect thoroughly after cleaning; discard chipped or cracked flasks
-Containers not heat-resistant or with screw-caps -Use only borosilicate (Type I) containers and automatic sealing and venting closures
Solutions Boiling when Door is Opened -Door opened too quickly -Do not open door until temperature gauge is below 212°F and pressure gauge is at "0". Do not touch or move a load of boiling solutions
 -Maladjusted slow exhaust valve -Notify FM
Indicator Shows Sterilization Not Complete -Load may be too large, too dense, or improperly loaded in chamber -Size of packs should not exceed 12" x 12" x 20"; weight should not exceed 12 pounds. Packs should rest on edge; all packs arranged to present the least possible resistance to passage of steam and air through layers of load.
-Time not sufficient for load -Increase time
-Sterilizer may be malfunctioning -Notify FM
Steam Leakage -Worn gasket -Call FM
-Door closed improperly. -Close properly (if problem continues, notify FM)-Close properly (if problem continues, notify FM).
Chamber Door Won't Open -Vacuum in chamber -Follow manufacturer's instructions
-Door-lock clutch is jammed -Follow manufacturer's instructions
-Gasket sticking to door frame -Notify FM

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