HIGH TEMPERATURE-GRAVITY AIR DISPLACEMENT STERILIZERS

OVERVIEW
  • Type of  steam sterilization
  • Slowest of the steam sterilizer
  • Required for certain items such as liquids
  • Most use high temperature method
  • Low cost, faster cycles,simple technology and leaves no chemical residue or by-products 
CYCLE PHASES
  1. Conditioning
    • Hot air to the top of  the machine
    • Cool air is forced to the bottom and out the drain
  2. Exposure
    • Prepares the machine for the next stage
    • Pressure and steam temperature to maximum of 250F
    • Time is based upon the time-temperature relationship
  3.  Exhaust
    • Removal of the steam through the discharge line
 
   4. Drying Phase
  • ·         Starts at the end of the exhaust phase
  • ·       Heated,  filtered fresh air and heat from the chamber walls re-vaporize and remove any liquid      and remove any liquid from the chamber
Loading Procedure
  • ·         Avoid overloading
  • ·         Avoid too tight packaging
  • ·         Use an absorbent shelf cover to line the sterilizer cart’s shelf
  • ·         Solid containers must be positioned
  • ·         Small items should be loosely placed in wire baskets
  • ·         Allow visible space between packs
  • ·         When combining loads, place hard goods on the bottom
  • ·         Packages must not touch chamber walls
  • ·         Basin sets should stand on edge
  • ·         Position textile packs so the layers within them are perpendicular to the shelf
  • ·         When possible, sterilize textiles and hard goods in separate loads
  • ·         Other than lumen, the items in the package must be completely dry
  • ·         Surgical instruments trays with perforated bottoms should sit flat on the shelf to maintain even instrument distribution, and to facilitate proper drainage
**CAUTION: NO SPUNBOND-POLYOLEFIN COMBINATIONS FOR PACKAGING**

Routine Monitoring
  • ·         External chemical indicator tape
  • ·         Internal chemical indicator strip
  • ·         BI
  • ·         The leak test
Trouble Shooting 
  •       If steam escapes from the safety valve or under the lid, the autoclave is not working correctly and it is merely steaming items at low pressure ( HLD, not sterilization)
  •   If steam escapes from the safety valve instead of the pressure valve, the pressure valve must be cleaned and inspected 
  •       If steam escapes form under the lid, the gasket (rubber ring) must be cleaned and dried or replaced.