GKE Australia Batch Monitoring SystemCodesquad2020-05-21T12:28:26+00:00
gke Steri-Record® Process Challenge Devices
to monitor steam sterilization processes
Fig. 1: Different sensitive process challenge devices, round section
In the sterilizer standards EN 285 and EN 13060 type tests are described, e.g. BD-Test or Helix Test according to EN 867-5. They are only testing the standard requirements of the sterilizers with-out any relation to the load.
They are quite often used as so-called batch monitoring systems and sold as various test sys-tems on the market to monitor the load. However, these tests have no relation to the load. There-fore, it cannot be automatically concluded that difficult loads can be sterilized successfully. A monitoring system for the load must not be adopt-ed to the sterilizer but must represent the load.
This adoption can be achieved in two ways:
Process Monitoring System (PMS):
The sterility of the load is assured if the sterili-zation process has been validated with a worst-case load. The continuous monitoring of the load shall be carried out with a test system which monitors the maximum performance of the sterilizer. Modern sterilizers provide much better performance than the required type test-ed mentioned above. For this purpose gke offers a variety of different PCDs (process challenge devices) with increasing sensitivities to monitor the process at highest level. These test devices are called process monitoring systems (PMS).
Batch Monitoring System (BMS):
If the characteristics of the load to be sterilized are known, a PCD can be designed and vali-dated to be more difficult to sterilize than the defined load using the method according to DIN 58921 (medical device simulator). gke has already tested several typical loads with the method according to DIN 58921 and offers special PCDs for Tattoo, Dental and Ophthal-mic loads. For these test systems separate data sheets with detailed information are avail-able.
The gke Steri-Record® Compact-PCD® consists of an external plastic casing with an internal stain-less steel tube and capsule holding the indicator.
The four colour-coded PCDs are available with two constructions:
round version with stainless steel bracket. This PCD can be put vertically on a loading rack or placed horizontally on the bracket.
oval version (green and orange): This PCD can be placed horizontally on the flat side of the PCD, suitable for small sterilizers (2.5 cm height).
All PCDs are re-usable and can be used for a considerable number of sterilization cycles.
Fig. 2: PCDs, round and oval construction
The gke PCDs are type 2 indicator systems according to EN ISO 11140-1, consisting of a „specific test load“ (Process Challenge Device = PCD) and „indicator“ (indicator strip). They have been validated from a laboratory accredited ac-cording to the standard EN ISO 17025 (test re-ports on request).
gke offers a variety of PCDs with different lev-els of difficulty. Using a test with the highest level which will still pass in a validated process the sterilizer is always tested at its limits. Failures that are not detected with standard methods will now be visible and the maximum possible safety to test sterilization processes can be guaranteed. If a process has been validated with a defined load and a suitable test system, this method secures the sterilization at the most difficult locations. This is not possible by only recording the physical data with documentation, e.g. with a printer.
The identification of a suitable PMS to monitor sterilization has to be verified during process vali-dation depending on the load.
The gke representatives support in the selection of the test system depending on the load.
1. PMS Compact-PCD®, colour: green
This PMS Compact-PCD®, colour: green, represents a challenging test concerning air re-moval and steam penetration that can be used for routine monitoring of simple hollow devices, tubes, porous loads and solid instruments. How-ever, this PMS is less demanding regarding air removal and steam penetration than the hollow load test described in EN 867-5.
2. PMS Compact-PCD®, colour: orange
The PMS Compact-PCD®, colour: orange, simu-lates the hollow load test according to EN 867-5. This type test is included in the standard for large sterilizers (EN 285) as well as in the standard for small class B sterilizers (EN 13060).
The standard EN 867-5 describes a test cycle with 9 injections of steam to 950 mbar. In this test cycle the hollow load test will be successfully penetrated, if a vacuum of 450 mbar will be reached in between each steam pulse.
3. HDH-PMS Compact-PCD®, colour: red
The HDH-PMS Compact-PCD®, colour: red, (High Demand Hollow) is used for routine moni-toring of complex instruments or long tubes, whereas the hollow load test according to EN 867-5 is not anymore sufficient.
To successfully penetrate the gke-HDH-PMS in the same test cycle a vacuum of at least 210 mbar is necessary.
The VHDH-PMS Compact-PCD®, colour: brown, (Very High Demand Hollow) makes increasing demands on the air removal performance. The test cycle according to EN 867-5 with 9 injections of steam requires vacuum cycles of at least 160 mbar to successfully penetrate the VHDH-PMS.
These data are only valid under laboratory condi-tions using a reproducible process in a test steri-lizer according to EN ISO 18472. All other varia-bles that affect the air removal and steam pene-tration are strictly defined in such a program and must remain unchanged in all test cycles.
Under real sterilization conditions the differences in performance between type test according toEN 867-5 and the gke HDH-PMS or gke VHDH-PMS may change considerably because day-to-day programs differ from the above mentioned test cycle. Usually less but deeper vacuum cycles are used.
Two indicator strips can be selected according to the program used and are available with different stated values:
1. 134°C, 3 min or 121°C, 15 min
2. 134°C, 18 min (prion cycle)
If all four bars of the chemical indicator turn from yellow (standard cycle) /pink (prion cycle) to black it is an indication of sufficient steam penetration inside the PCD.
Fig. 4: Colour change of a standard indicator strip. If using an indicator strip for prion programs the initial colour is pink
Sufficient temperature, time and steam penetration
Insufficient air removal and steam penetration
Temperature achieved, but no air removal and no steam penetration
Insufficient temperature, no air removal and no steam penetration
This result ensures air removal and steam penetration into the whole load under the condition that the PCD is representing the load configuration.
Indicator strips for standard and prion sterilization cycles are available.
Test of a sterilizer, if the specification requirements are according to the standard, lower or higher.
Monitoring of sterility inside of complex hollow instruments, tubes and porous goods not provided by recording pressure, temperature and steam quality in the chamber and/or using ex-posed indicator strips.
Cost effective due to multiple use. Only one indicator strips is required for each sterilization process instead of one in each pack.
Ease interpretation of the results due to precise colour change.
Reproducibility of the results for a long period of time.
All information relevant to the process is supplied on completion of the process so that the authorized person can release the batch with-out opening the packs.
Environmentally friendly, no unnecessary waste.
The graduated colour change of the indicator bars informs about the kind and magnitude of air removal and steam penetration inside the sterilizer and non-condensable gases in steam.
The indicator colour chemistry is a non reversible chemical reaction and remains colourfast over time if they are not stored with other chemicals.
gke self-adhesive labels simplify recording with the gke Steri-Record® documentation system.
All gke chemical indicators are protected from bleeding by a polymer binder and surface coating can be disposed with normal garbage.
Selection between four different versions of PMS Compact-PCD® depending on the air removal program used and the load to be sterilized.
The screw cap consists of a highly thermal resistant material and stainless steel sandwich construction that protects hands from high temperatures. The chemical indicator may be easily removed and evaluated on completion of each cycle.
The Compact-PCD® can be used for a considerable number of cycles. All important parts are made of stainless steel or thermal resistant polymers.
Each start-up kit contains of a Compact-PCD and 100 integrating indicator strips for standard steam sterilization processes. All test devices are also available separately. The indicator strips are available as refill packs for standard and prion steam sterilization processes and also contain a sealing kit for the screw cap.
1. Start-up kit and process challenge devices / Process monitoring systems (PMS)
Indicator strips for all gke PMS in standard steam sterilization
134° C, 18 min
Indicator strips for all gke PMS in steam
To all article numbers a 3-digit alpha code is added. The additional letter code refers to the language and/or customized and plug version. It is only added on the outside label, the inside of the pack is identical to the article numbers on the above tables.