Hand Hygiene, Environmental Cleaning, and Disinfection and Sterilization
Hand hygiene, cleaning, disinfection, and sterilization questions test whether you can match the method to the organism, the item, and the risk level. Expect the WHO 5 Moments, alcohol versus soap and water, Spaulding classification, contact time, and sterilization monitoring.
Core rules
- WHO 5 Moments: before touching a patient; before a clean/aseptic procedure; after body fluid exposure risk; after touching a patient; after touching patient surroundings.
- Alcohol-based hand rub is preferred for routine decontamination when hands are not visibly soiled. Use soap and water for visible soil, after restroom use, and for C. difficile or norovirus because alcohol does not reliably kill spores or non-enveloped viruses.
- Hand hygiene technique: cover all surfaces, rub until dry; soap and water for at least 20 seconds. Keep natural nails short; avoid artificial nails and nail polish in direct care.
- Environmental cleaning: clean visible soil first, then disinfect. High-touch surfaces include bed rails, call buttons, doorknobs, keyboards, and IV pumps. Use an EPA-registered disinfectant with the correct contact time; do not wipe dry immediately.
- Spaulding classification: critical items enter sterile tissue or vasculature-sterilize; semi-critical items contact mucous membranes or nonintact skin-high-level disinfection; noncritical items contact intact skin-low-level disinfection.
- Sterilization methods: steam autoclave, ethylene oxide, hydrogen peroxide gas plasma, and others. Monitor with mechanical, chemical, and biological indicators; biological indicators are the most reliable.
- Endoscope reprocessing requires precleaning, leak testing, manual cleaning, high-level disinfection, rinsing, drying, and storage.
Worked example
A flexible endoscope is used on a patient. It is semi-critical because it contacts mucous membranes. The correct process is manual cleaning, high-level disinfection with an EPA-registered product, thorough rinsing with sterile or filtered water, and drying before storage. A biological indicator is not routinely used for high-level disinfection; it is used for sterilization. If the disinfectant contact time is shortened, the process is invalid.
Traps
Do not use alcohol for C. difficile. Do not skip manual cleaning before disinfection-organic soil inactivates disinfectants. Do not confuse high-level disinfection with sterilization. Do not treat contact time as optional.