Sterifast Self-Contained Biological Indicator EO
Self-Contained Biological Indicators (SCBI) for monitoring Ethylene Oxide (EO) sterilization processes, with a 24-hour incubation readout. Each unit consists of a thermoplastic vial and cap, a crushable media ampule containing modified Trypticase Soy Broth (TSB) with a pH indicator, and an inoculated carrier disc of Bacillus subtilis var. nigra (ATCC 9372) at a population level of 10⁵. The modified TSB medium transitions from its initial blue-green color to yellow and/or develops turbidity in the presence of bacterial growth, providing a reliable biological confirmation of EO sterilization efficacy.
Key Features
- Self-contained format: no separate culture media handling required
- Population level of 10⁵ Bacillus subtilis var. nigra (ATCC 9372) spores per disc
- Integrated chemical indicator (CI) strip on the vial label, transitioning from purple to pink upon EO exposure
- Color-change readout: blue-green (negative) to yellow and/or turbidity (positive)
- 24-hour incubation at 37°C for result readout
- Designed for use in the most challenging-to-sterilize position within the load
- Not for refrigeration; contains live cultures requiring careful handling
Technical Data
| Specification | Value |
| Sterilization Process | Ethylene Oxide (EO) |
| Microorganism | Bacillus subtilis var. nigra (ATCC 9372) |
| Population | 1.0 to 5.0 × 10⁵ per disc |
| Incubation Temperature | 37°C |
| Incubation Time | Minimum 24 hours |
| Dimensions | 10 mm x 45.5 mm |
| Packaging | 100 units/box |
| Chemical Indicator | Integrated CI strip; purple to pink color change upon EO exposure |
| EO Resistance (D-value) | < 1 minute at 50°C, 2.5 mg/L EO |
| Post-Market Criteria | Population: 50% to 300% of certified population |
| Storage Temperature | 20°C to 25°C average (excursions 15°C to 30°C permitted) |
| Storage Humidity | 20% to 70% relative humidity |
| Storage Conditions | Do not freeze; do not refrigerate; keep away from sunlight; keep dry |
| Disposal | Autoclave for ≥30 minutes at 121°C, or per other validated disposal cycle |
Applications
- Routine biological monitoring of EO sterilization cycles in industrial and healthcare settings
- Process validation and efficacy verification for EO sterilizers
- Recommended for inclusion with every sterilization load to ensure maximum control of sterilized goods