Some new steam-sterilizers have preset the holdingtime in the Bowie & Dick-program to 15 - 30 seconds. By running the chemical testpack, you still get a satisfactory result. The manufacturer declares that this has something to do with the long periods of high temperature prior to the sterilization phase, but they will not document that.
Is this acceptable from an EN 285 (EN 867) point of view?

Best regards,

Lars Nygaard
Dept. of Infection Control,
The National Hospital
Norway

Lars

Regardless of the test pack utilised for the daily test. The same protocol, principlies and standards applies to its use. The test is performed daily after a warm up cycle, before the autoclave is used for the production of a sterile product. The basic principal is that with satisfactory air removal, steam penetration will occur throughout the test pack and the test will indicate a pass and the reverse inadequate air removal will prevent steam penetration and indicate a fail.

Different manufacturers put a spin on their interpretation of results for the commercialisation and sale of the products.

The manufacturers pre-setting of Bowie & Dick cycle hold times is a practice employed to support HTM2010 section 13:43 that states Holding time for Bowie & Dick (class B indicators) should be between 3.3 mins and 3.5 mins and should not exceed the max time as the indicator may change were failure cannot be indicated.

Again Lars, to emphasise as stated in EN 867 pt 4, either using reusable or one shot tests the testing protocol should reflect the standard and the manufacturers tend to follow standards. If in doubt abouth holding times thermometric performance qualification is good practice in clarification and compliance of the choosen Bowie & Dick test packs and the pre-progammed cycles choosen to process them.