DEAR SIR,

BOWIE DICK TEST IS THE PREFERRED METHOD TO CHECK THE PERFORMANCE OF PRE VACUUM STERILIZER BUT RECENTLY I CAME ACROSS A HOSPITAL WHICH USES AUTOCLAVE TAPE IN "X" FORMAT AND THAN IT IS PACKED FOLLOWING AAMI PACK STANDARD.

I WOULD LIKE TO KNOW WHETHER THIS "X" METHOD IS AN ACCEPTABLE METHOD OR IT IS USED TO SAVE COST BY COMPROMISING THE VALIDATION PROTOCOL.

BEST REGARDS
MADHAV PAREKH
PHARMACONCEPT

Dear Madhav Pareka,
I am not certain what you are referring when you say they use autoclave tape in an 'X' format.
To make the test sheet for the Bowie-Dick test, begin with a piece of paper at least 8" x 11". Place a strip of autoclave tape from one corner to the other, going diagonally across the paper. A second strip of tape is placed connecting the other two corners. The third piece of autoclave tape is placed crossing the center of the sheet, from left to right. The last piece crosses the center, and goes from the top to the bottom of the paper. Therefore, it looks something like an "X" with a "t" on top of it. This test sheet is placed in the center of a pack. The AAMI pack standard: made with freshly laundered, folded 100% cotton surgical towels, and the test pack should be 10 to 11" high, 12" wide, and 9"deep.
Reading the test can be subjective. Evenness of color change, and not the intensity of the color change is what you look for. Any variation in color indicates a failure. But, how different can a shade of gray be, before you name it different? Different people distinguish different levels of gray. This is a place where the quality of the ink in the autoclave tape could make a difference.
I hope I have answered your question fully. If I have misunderstood the 'X' format, please give a more detailed explanation of this.
Regards, Pete Bobb