Four-hour, green cap, Rapid Readout Biological Indicator for EO Sterilization . Biological indicators and test packs that monitor the effectiveness of the EO sterilisation process and provide results within four hours.

• After sterilisation, the vial is 'crushed' to join the growth media with the processed spore strip
• The BI is incubated for 4 hours for a fluorescent readout
• Test packs present a challenge to the sterilization process as do the AAMI recommended packs
• Every load monitoring and quarantining can eliminate recalls

The self-contained BI for all EO cycles consists of a Bacillus atrophaeus spore strip; sealed glass ampule with growth medium and bromothymol blue pH indicator dye system; green colour-coded cap with holes for sterilant penetration and a spunbonded olefin (polyethylene) filter as a bacterial barrier, and a chemical indicator on the label that changes to green when processed.