The Bowie Dick Test Pack is a unique combination of advanced Browne Intelligent Ink Technology and the original Bowie Dick concept. A successful test confirms that steam penetration into a test pack is rapid and even and, by implication, that air and other non-condensable gases have been effectively removed. The chemical indicator sheet at the centre of the pack shows a defined colour change from yellow to dark blue/purple when exposed to a specific combination of time, temperature and steam.

The Browne 121 ˚C TST Bowie Dick Test Pack has a maximum plateau of 8.3 minutes. This enables the sensitivity of a 121 ˚C Bowie Dick Test to be comparable to that of a 134 ˚C Bowie Dick Test.