Gaseous sterilization
Start with the big picture
Gaseous sterilants act mainly through alkylation or oxidation, damaging proteins and nucleic acids. Ethylene oxide is prominent for heat- and moisture-sensitive devices such as plastics, electronics, endoscopes, and catheters, but requires aeration to remove residues and careful attention to its hazards. Formaldehyde gas is used for fumigation and biosafety cabinets, while hydrogen-peroxide plasma offers a low-temperature process with water and oxygen as by-products. Plasma is unsuitable for some materials and device forms, including cellulose, liquids, and long lumens. Ozone can sterilize compatible metals and plastics. Across these methods, diffusion limits mean powders, oils, and sealed liquid ampoules are not suitable. Indicators and method-specific conditions help support process monitoring.
What you'll learn
- Identify the principal gaseous sterilants and their mechanisms of microbial inactivation.
- Describe common applications of ethylene oxide and formaldehyde gas.
- Compare material compatibility and limitations of plasma and ozone sterilization.
- Recognize why some items cannot be sterilized by gaseous methods.
- Distinguish the biological indicators associated with ethylene oxide and plasma.
Continue your study
Work through the complete notes and reinforce the topic with the study tools available in the full lesson.
