For monitoring Steam sterilization processes between 121 ºC and 135 ºC, ensuring an adequate control of the effectiveness of sterilization processes (temperature, time, quality of steam).
Purple ink was developed to turn to green when a theorical spores population reaches its kill time, indicating that integration condition has been reached. This condition is calibrated with the kill time of a 106 Geobacillus stearothermophilus spore population, calculated in a BIER (Biological Indicator Evaluator Resistometer).