The MMM Group Bowie-Dick Helix test conforms to the DIN EN ISO 11140-4 standard and objectively checks your sterilization process for air removal and steam penetration. At full steam penetration the indicator changes color from blue to pink. An incomplete color change signals an insufficient exposure of the indicator to steam, which indicates a defective process. MMM indicators contain no heavy metals or toxic substances. Once the color of the indicator has changed, no further change in color will occur. This provides absolute, documented certainty.