Bowie-Dick test pack

For porous loads, two other monitoring techniques are in use to give assurance of sterility where there is a risk of air entrainment, superheating, etc. These are the Bowie-Dick test pack and the Lantor Cube. It should be emphasized that these are used in rather special applications and would be of little significance to fluid loads or nonporous solid loads. 

The Bowie-Dick Test Pack The Bowie-Dick standard test pack consists of a series of folded stacked towels. Strips of heat-sensitive tape are placed from comer to comer to form a Saint Andrew s cross pattern at various depths within the pack. The towels are fairly tightly wrapped, sealed with tape and placed in the autoclave along with a routine load. 

The Lantor Cube The Lanior cube was developed as a reusable and more reliable ahemativc to the Bowie-Dick towel pack. It consists of a 15 cm cube of laminated polypropylene supplied in two halves. A sheet of paper carrying strips of heat-sensitive indicator tape is placed between the two sections of the cube and clamped in place. Interpretation is the same as for the Bowie-Dick test pack. 

In prevacuum autoclaves, problems are created by the removal of air and the air-insulation systems. A specific test called the Bowie Dick test (12), was developed to evaluate the abflity of prevacuum sterilizers to provide rapid and even steam penetration which includes the abflity to eliminate air from the chambers, and prevent air from lealdng back during the prevacuum phase. The test utilizes a pack of specific constmction (or its proven equivalent) placed in the empty chamber and exposed to specific test conditions (9,12). The pack contains a chemical indicator sheet. A correctly fimctioning sterilizer produces a uniform color change. A nonuniform color change indicates poor steam penetration and the possible presence of air which requires the attention of a qualified mechanic. The daily testing of all porous load sterilizers is recommended (1,9,10). 

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