The Bowie-Dick-Test must be performed at least daily upon starting work as a function test for large steam sterilizers acc. to DIN EN 285. It is used to prove successful deaeration and steam penetration. A cloth package of 7,0kg and Bowie-Dick-test sheets acc. to DIN EN 867, part 3 must be used to perform this test.

Bowie-and-Dick-Simulation Systems are available in order to ease and minimize the effort for the cloth package. We recommend to use them if it has been verified that the alternative test systems are equivalent to the Bowie-Dick-Test. EN 867-4 and EN 867-5 describe such alternative systems. Please note that the Bowie-Dick-Test only provides reliable results if the holding time of 3.5 minutes at 134°C is maintained. Some older sterilizer modeals may not be equipped with a respective test program. In such cases we recommend upgrade of the sterilizer with a suitable test program.
 

Due to the classification of the sterilisation processes of small steam sterilizers acc. to EN 13060 in type classes B, N and S standardization for performance examination of these sterilizers is currently developed. To test sterilizers with fractionated vacuum process, Bowie-Dick-simulations test packages can be used if they comply to the requirements of EN 867-5.
 

The Bowie-Dick-Test performed upon start of operation is not a guarantee of proper sterilization. When used with a central steam supply unit, the throughput of steam during the day can lead to generation of mixed gasses which were not present during the startup test. When using integrated steam generators, the amount of inert gas can exceed the maximum concentration according to DIN EN 285 appendix B in the course of the day due to the quality changes in the demineralized water. We therefore recommend use a cycle control system when running sterilization cycles.
 

Until the new European Standard takes effect, bacteriological tests of small steam sterilizers are to be performed according to DIN 58946 part 8. The quantity of needed bio-indicators and their distribution depends on the size of the sterilization container resp. the sizes of the sieve tray and can be taken from DIN 58946 part 8.
 

Bacteriological tests of Large Steam Sterilizers are to be performed acc. to Standards DIN 58946 / EN 285. The required quantity and distribution of bio-indicators can be taken from the Standards DIN 58946 part 6, table 2 / EN 285 chapter 17.1.2.5. To perform the bacteriological tests, please contact our Customer Service.

Bio-Indicator for bacteriological test 1 pc., incl. evaluation Art.-No. 009292   Bio-Indicator-Set (for 1 StU Sterilizers) for bacteriological test 5 pcs., incl. evaluation, without illustration Art.-No. 008935

For the bacteriological test of formaldehyde sterilizers up to 150 dm³ useable space, 10 test devices (helix)*, each with one bio-indicator must be used according to DIN EN 14180 and prEN 15424. 9 of the 10 test devices are wrapped like the sterilization material. They have to be distributed in the load within the sterilization chamber in such a way that it is difficult for the steam formaldehyde mixture to reach them. The tenth helix remains wrapped or unwrapped outside of the sterilization chamber for positive control. After the end of sterilization all helix devices inclusive indicators (i. e. the indicators may not be removed from the helix) are sent directly to a hygiene institute for evaluation. The result of the evaluation is sent via post or by fax.

If possible the testing of the sterilization process should be performed immediately after receipt of the indicators. Storing the bio-indicators for formaldehyde sterilization in a refrigerator is only possible for a limited time.

*According to DIN 58946-16 non-metallic test devices are recommended for the microbiological test.

Bio-Indicator test set for cycle control consisting of 10 x WEBECO-helix with inserted bio-indocator strip each (WEBECO-helix on loan) Art.-No. 008559

In addition to the legally mandadory tests we recommend consequent monitoring of each cycle. Cycle control systems should be used for such monitoring. These can show deviations from the nominal condition directly after each sterilization cycle. Examination at longer time intervals performed with bio-indicators are not recommended. Without additional tests, cycles performed in the meantime could be erroneously approved as sterile. It is then possible that the operator is unable to prove that possible infection was not caused by the treated sterile material (burdon of proof).

Cycle control sets can be used for checking each individual cycle. They are representative for the entire load of the sterilizer. The sets are intended for use in sterilizers with fractionated vacuum process. They consist of a test device (helix) with chemo-indicator strips. We offer cycle control sets for steam and formaldehyde sterilization.

For Small Steam Sterilizers (type B = fractionated vacuum process): A test device with a chemo-indicator strip is sterilized together with the sterilization material. The test device simulates loads of classification, "hollow devices A", acc. to EN 13060.

For cycle control of Large Steam Sterilizers the test device (helix) with a chemo-indicator strip can also be used and sterilized together with the sterilization material.

For Formaldehyde Sterilizers A test device acc. to DIN EN 14180 and prEN 15424 is defined. It is sterilized together with the sterilization material.
 

Cycle Control Set Steam Sterilization

Chemo-Indicator Test set for cycle control, deaeration and steam penetration test, consisting of 1 x WEBECO-helix, 100 chemo-indicator strips and instruction color change of indicator from yellow to black Art.-No. 008934

Cycle Control Set Formaldehyde Sterilization

Chemo-Indicators Test set for cycle control, consisting of 1 x WEBECO-helix, 200 chemo-indicator strips and instruction color change of indicator from blue to green Art.-No. 008560

To perform the test a chemo-indicator is inserted into the test device. Subsequently the system is subjected to a sterilization process. After the end of the sterilization the test device is opened and the color change of the indicator is examined. The sterilization process is to be regarded ok if the indicator shows the color change which was specified by the manufacturer. The indicator is glued into a cycle control sheet for documentation
example as PDF-file, (free Acrobat-Reader needed for viewing)

Compared to single indicators which must be placed in the center of each package or container, there are following advantages when using cycle control sets:

• the result for the complete load can be seen immediately
• individual examination of each wrapping unit can be omitted
• significantly improved cost-effectiveness compared to individual control
• reduced documentation work

Indication: The test device is adjusted to certain indicators. When using other then the specified indicators we cannot guarantee a proper test result. Protect indicators from exposure to light.
 

Use of control indicators examines whether the process to which the products were subjected has been properly performed.

Control indicators (e.g. ATI Steam Clox) are used especially for such small sterilizers that are not designed to sterilize products with cavities (sterilizers without fractionated vacuum process). They should be placed at the location with the most difficult sterilization conditions. Generally this is in the middle of the individual package or container. Control indicators are available for 121°C and 134°C programs for steam sterilization. Based on the color change and the operation instruction for the indicators the quality of the sterilization process can be seen directly after opening the package and before using the sterile material.
 

Treatment indicators are used to determine if the material has been subjected to a sterilization process or not. A treatment indicator changes color after a sterilization process. A color change does not, however, authorize the statement that the treated material is sterile. It is not possible to make a reliable statement on the quality of the sterilization process based solely on treatment indicators.

Treatment indicators are available as adhesive tape, self-adhesive dots, labels etc.
 

Treatment Indicators Formaldehyde Sterilization

	Adhesive Dots to verify the treatment of individual wrapping units 250 pcs, indicator color change from blue to yellow Art.-No. 009289
	Treatment Indicator Strips to verify the treatment of the load 1100 pcs, indicator color change from yellow to light brown Art.-No. 009288

Labels with Treatment Indicators

Labels with steam treatment indicator, perforated, 1000 pcs. (Not illustrated) Art.-No. 029960   Labels with steam and formaldehyde treatment indicator, perforated, 1000 pcs. Art.-No. 027342

The cycle documentation records all phases, measures working steps and machine functions which refer to the sterile material of a cycle and which are directly related to the success of the sterilization process.

It is the goal of the cycle documentation to record and verify the correct sterilization of each of the sterile materials treated in this sterilizer. If the cycle documentation is patient-related the sterile materials used at the patient and the respectve cycle number must additionally be recorded in the patientīs file.

For computer-aided cycle documentation WEBECO offers the PC program " Chargen-Data" (for sterilizers from 1StU chamber volume).