5.1 Sterile Storage Area Requirements
Key Takeaways
- Sterile storage must be a controlled-access area with limited entry to authorized personnel only
- Temperature should not exceed 75°F (24°C); ideal range is 68-73°F (20-23°C)
- Humidity should be maintained between 30-60% (some standards allow up to 70% max)
- Minimum 4 air exchanges per hour with positive air pressure relative to surrounding areas
- Items must be stored at least 8-10 inches off the floor, 18 inches below ceiling sprinklers, and 2 inches from outside walls
- Shelving must be smooth, non-porous, and easily cleanable — no corrugated cardboard for storage
- Sterile storage should be located adjacent to the sterilization area for efficient workflow
- Temperature and humidity must be monitored and documented at least daily
Sterile Storage Area Requirements
The sterile storage area is where processed items wait until they are needed. Maintaining proper environmental conditions is essential to preserving the sterile barrier integrity of packaged items.
Environmental Requirements
| Parameter | Requirement | Rationale |
|---|---|---|
| Temperature | Maximum 75°F (24°C); ideal 68-73°F (20-23°C) | Elevated temperatures accelerate material degradation and promote microbial growth |
| Humidity | 30-60% (max 70% per ASHRAE) | High humidity promotes microbial growth; low humidity causes static and material brittleness |
| Air exchanges | Minimum 4 per hour | Removes airborne contaminants; maintains air quality |
| Air pressure | Positive relative to surrounding areas | Prevents contaminated air from entering storage area |
| Lighting | Adequate for inspection and retrieval | Should not generate excessive heat |
Monitoring:
- Temperature and humidity must be recorded at least daily (many facilities use continuous electronic monitoring)
- Out-of-range readings require immediate investigation and corrective action
- Records should be maintained per facility policy (often minimum 3 years)
Storage Placement Rules
| Rule | Specification | Reason |
|---|---|---|
| Height from floor | At least 8-10 inches | Prevents contamination from floor cleaning, mopping, and flooding |
| Distance from ceiling | At least 18 inches below sprinkler heads | Fire code compliance; prevents water damage from sprinkler activation |
| Distance from walls | At least 2 inches from outside walls | Prevents moisture transfer from exterior walls (condensation) |
| Shelving type | Smooth, non-porous, cleanable (wire or solid) | Porous surfaces (cardboard, wood) harbor organisms |
| No floor storage | Items must NEVER be stored directly on the floor | Even in closed containers, floor-level storage is prohibited |
Access Control
Sterile storage is a restricted area:
- Only authorized personnel should enter
- Traffic through the area should be minimized
- Doors should remain closed (self-closing doors recommended)
- Environmental conditions are disrupted by frequent door opening and unnecessary traffic
- No eating, drinking, or personal items in the storage area
- Clean hands and appropriate attire required for entering and handling sterile items
Shelving and Organization
Best Practices:
- Label all shelves clearly with content descriptions
- Organize by department, procedure type, or alphabetically — whatever system works best for your facility
- Place most frequently used items at accessible heights (waist to shoulder level)
- Use closed cabinets when possible to provide additional barrier protection
- Keep storage area clean and free of clutter — schedule regular cleaning
- No corrugated cardboard in the sterile storage area (harbors insects and cannot be properly disinfected)
Event-Related vs. Time-Related Sterility
Event-Related Sterility (Current Best Practice)
The concept that an item remains sterile until an event occurs that compromises the sterile barrier:
Events that compromise sterility include:
- Packaging torn, wet, or punctured
- Package dropped on the floor
- Seal broken or opened
- Exposed to moisture (water, condensation)
- Contaminated by handling with soiled gloves
- Environmental conditions exceeded (temp/humidity)
Under event-related sterility, a package with an intact barrier remains sterile indefinitely, as long as it has been stored properly and no compromising event has occurred.
Time-Related Sterility (Older Practice)
Assigns an expiration date after which the item is considered no longer sterile, regardless of packaging condition:
- Based on packaging material, storage conditions, and handling
- Still required by some facilities or regulatory bodies
- Typical expiration periods historically: 30 days (dust covers), 6-12 months (sealed packaging)
Current Recommendation:
AAMI, AORN, and most current standards support event-related sterility — the package is sterile until an event compromises it, not until a calendar date passes. However, facilities must follow their own policy, and some regulators still require time-related dates.
Handling Sterile Items
- Handle packages carefully — rough handling can compromise the sterile barrier
- Never stack heavy items on top of lighter sterile packages
- Check packages for integrity before distribution — any compromise = reprocess
- Use clean, dry hands or clean gloves when handling sterile packages
- Transport sterile items in covered carts or clean containers
Sterile items must be stored at least how far from the floor?
Under event-related sterility, a properly packaged sterile item:
The maximum temperature in a sterile storage area should not exceed: