Bowie-Dick test
Also called: B-D test, air-removal test
Bowie-Dick test — A daily Class 2 test that checks air removal and steam penetration in a pre-vacuum steam sterilizer, run in an empty chamber before the first load.
The test is named after J. H. Bowie and J. Dick, who described it in 1963. A test pack carrying an indicator sheet is placed alone in the chamber and run on a dedicated cycle, usually 134 °C for 3.5 minutes. A uniform colour change across the sheet shows steam reached the centre of the pack; a paler patch in the middle shows trapped air, a leak or non-condensable gases.
Ready-made packs are made to ISO 11140-4 as an alternative to the standard towel pack in ISO 11140-3 and EN 285. A failed test means the sterilizer should not be used for loads until the cause is found, the fault corrected and the test passed.
Related termsChemical indicatorSteam sterilizationClass B sterilizerISO 11140-1