Sterilization procedures should be monitored using biological, mechanical, and
chemical indicators. Biological indicators, or spore tests, are the most accepted
means of monitoring sterilization because they assess the sterilization process
directly by killing known highly resistant microorganisms (e.g., Geobacillus or
Bacillus species). However, because spore tests are only done weekly and the
results are usually not obtained immediately, mechanical and chemical
monitoring should also be done.
Mechanical and chemical indicators do not guarantee sterilization; however,
they help detect procedural errors (e.g., overloaded sterilizer, incorrect
packaging) and equipment malfunctions. Mechanical and chemical monitoring
should be done for every sterilizer load.
Mechanical monitoring involves checking the sterilizer gauges, computer
displays, or printouts, and documenting in your sterilization records that
pressure, temperature, and exposure time have reached the levels
recommended by the sterilizer manufacturer. Since these parameters can be
observed during the sterilization cycle, this might be the rst indication of a
problem.
Chemical monitoring uses sensitive chemicals that change color when exposed
to high temperatures or combinations of time and temperature. Examples
include chemical indicator tapes, strips, or tabs and special markings on
packaging materials. Chemical indicator results are obtained immediately
following the sterilization cycle and therefore can provide more timely
information about the sterilization cycle than a spore test.
A chemical indicator should be used inside every package to verify that the
sterilizing agent has penetrated the package and reached the instruments
inside. If the internal chemical indicator is not visible from the outside of the
package, an external indicator should also be used. Chemical indicators help to
dierentiate between processed and unprocessed items, eliminating the
possibility of using instruments that have not been sterilized.
Do not use instrument packages if mechanical or chemical indicators indicate
inadequate processing. Chemical indicators should be inspected immediately
when removing packages from the sterilizer; if the appropriate color change did
not occur, do not use the instruments.
No comment