Why decontamination comes first
Decontamination is the process of removing soil and reducing the number of microorganisms on a reusable medical device so that it is safe to handle, inspect, and further process. It is the foundation of the entire sterile processing workflow. The golden rule of sterile processing is simple but absolute: "If it isn't clean, it can't be sterilized."
Organic soil such as blood, tissue, and body fluids protects microorganisms from the killing action of heat, chemicals, and other sterilants. Residual soil can also dry onto an instrument, harden, and become nearly impossible to remove — and bioburden (the population of viable microorganisms on an item) left behind can shield spores from the sterilization process entirely.
The one-way workflow
Sterile processing departments (SPD) are designed around a strict "dirty-to-clean," one-directional flow. Contaminated items always move from the soiled/decontamination area toward the clean preparation area and never travel backward. This prevents cross-contamination of clean and sterile items.
🔑 Key concept: Spaulding Classification
E.H. Spaulding classified devices by infection risk to determine the level of reprocessing required:
- Critical items — enter sterile tissue or the vascular system (e.g., surgical instruments, implants). Must be sterilized.
- Semi-critical items — contact mucous membranes or non-intact skin (e.g., flexible endoscopes, respiratory equipment). Require high-level disinfection at minimum.
- Non-critical items — contact only intact skin (e.g., blood pressure cuffs, bed rails). Require low- to intermediate-level disinfection.
Point-of-use treatment & transport
Decontamination effectively begins at the point of use — in the operating room or procedure area — where staff keep instruments moist and remove gross soil. Keeping soil from drying makes cleaning in the SPD far more effective.
- Remove visible gross soil with a sponge or wipe and keep instruments moist (use a pre-treatment spray, gel, or a moistened towel — not saline, which causes pitting and corrosion).
- Open hinged instruments, disassemble multi-part devices, and flush lumens as appropriate.
- Contain and transport in a closed, leak-proof, puncture-resistant container labeled with a biohazard symbol.
- Transport promptly to the decontamination area following the facility's time limits.
Manual and mechanical cleaning
Manual cleaning
Performed for delicate, complex, or lumened instruments that cannot tolerate automated processing. Always clean under the surface of the water to prevent aerosolizing contaminants, using soft brushes sized to the lumen and an enzymatic or neutral-pH detergent diluted per the manufacturer's instructions for use (IFU).
Mechanical cleaning
- Ultrasonic cleaner — uses cavitation (microscopic bubbles that implode) to remove fine soil from hard-to-reach areas. Used after gross soil is removed.
- Washer-disinfector — automates wash, rinse, and thermal disinfection; improves consistency and reduces staff exposure.
- Cart washer — cleans case carts and large equipment.
Personal protective equipment (PPE)
The decontamination area is a wet, contaminated environment. Technicians must wear full PPE to protect against splashes and sharps:
- Fluid-resistant gown or jumpsuit
- General-purpose utility gloves (not exam gloves)
- Face protection — mask plus full face shield or goggles
- Fluid-resistant shoe covers and a hair covering
🔑 Remember
The decontamination area is kept under negative air pressure relative to surrounding areas, with around 10 air exchanges per hour and a temperature of roughly 60–65°F (16–18°C), to contain contaminants.
Ready to test yourself?
Reinforce Decontamination with quizzes and flashcards.