Dear Sir,

Sub: Failure of Bowie & Dick Test

Appreciate if you could provide some tips as to why the Bowie & Dick Test is failing. When the following parameters necessary to pass are met.

Action before the test:
Checked all the one way valves, the steam traps, piston valve seats, vacuum pump, door seals, solenoid valves, etc.

1. Prevacuum pulse is ok. Draws a vacuum of less than 100 mbar.(No. of pulses 4)
2. Sterilization temperature reaches 134 Degrees C
3. Holding time 3.5 Mins.
4. Over pulse during pretreatment is between 1002 mbar to 1012mbar
5. Leaktest is ok not noticed any leak, for a period of 15 mins.

ETS (3M) test was performed along with Bowie & Dick (Browene), it was noticed that ETS passed and the Bowie & Dick (Browene) test failed showing a very little yellowish micro dots, in the center of the sheet.
Appreciate your expert advice on this matter.

Best regards,
Joe,
Kuwait

Hi

We also on the Isle of Wight had the very same problem. Ours turned out to be contamination in the Steam.

When we did our first Bowie in the morning it also failed with the same, but 9 times out of 10 the second attempt would pass, but checking with our TP he investigated the steam and thats what it turned out to be.

Now everything is fine.

Hope that will help.
Simon
Isle of Wight

Hi.
Simon is right. The quality of the steam, or beeing more accurate the quality of the water is most important and definitly affect the B & D test. You must refer to the recomendation provided by the manufacturer.
miki

Dear sir/madam,

I am experiancing similiar problems to Joe. I have had the steam quality tested and we are compliant with HTM2010, non condensables are fine, dryness, etc are all ok yet i keep getting failed bowie dick test`s on one sterilizer.

As with Joe, the leak rate test is conducted and all is fine?

The steriser is on of two steriliser serviced by the same steam supply? Any help and comments would be useful.

We are planning to check the vac pump and line!

Thanks
Lee Simpson

Hi Joe,

In order to overcome your problem you must try different types of Bowie Dick other than the one you are using and contact the company who sold you the sterilizer. It's very unlikely to have a Bowie Dick failure and an ETS pass result while the other way around is more probable. you can also contact your local 3M representative.

Natali