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CRCST 7 min readJuly 14, 2026

Sterile Storage & Inventory Management (FIFO Explained)

How sterile storage and inventory management work — FIFO rotation, event-related sterility, and what the CRCST exam tests in this often-overlooked domain.

Houcine Boutam

Houcine Boutam

15+ Years in Sterile Processing · BS Healthcare Science

The Most Overlooked CRCST Domain

Sterile Storage, Transport & Inventory Management makes up only 9% of the CRCST exam — smaller than decontamination, prep & pack, or sterilization — which means many candidates under-study it. That's a mistake: this domain has clear-cut, memorizable facts that are easy points if you know them, and easy losses if you don't.

Event-Related Sterility (ERS)

Most modern sterile processing departments use event-related sterility rather than time-based expiration dates. Under ERS, a sterile item remains sterile indefinitely, as long as the packaging integrity is maintained — sterility is lost due to an event (a breach), not the passage of time.

Events That Compromise Sterility

  • Torn, punctured, or wet packaging
  • Seal failure or loss of package integrity
  • Exposure to moisture or contamination
  • Being dropped or crushed
  • Storage in an uncontrolled environment (excess humidity, dust, pests)

The "If in Doubt, Throw It Out" Rule

If a technician cannot confirm that a package's integrity is fully intact, it must be treated as non-sterile and reprocessed — regardless of how long ago it was sterilized.

Sterile Storage Requirements

Proper sterile storage environments must maintain:

FactorRequirement
TemperatureTypically 68–73°F (per AAMI recommendations; facility policy may vary)
Relative humidityGenerally below 70%
ShelvingSolid-bottom or wire shelving, at least 8–10 inches off the floor, 18 inches from the ceiling, and 2 inches from outside walls
TrafficLow-traffic, restricted-access area
Air qualityPositive pressure airflow relative to adjacent areas

FIFO: First In, First Out

FIFO (First In, First Out) is the standard inventory rotation method in sterile processing. Newly sterilized or newly received items are placed behind existing stock, so older items are used first.

  • Prevents items from sitting unused indefinitely
  • Reduces unnecessary reprocessing due to packaging degradation over long storage periods
  • Applies to both sterile processed trays and disposable supply inventory

Inventory Management Systems

Most departments use an instrument tracking system (barcode or RFID-based) to manage inventory. These systems typically track:

  • Instrument and tray location
  • Sterilization date and cycle/load number
  • Which technician processed the item
  • Loaner tray and consignment inventory
  • Par levels for supply reordering

Transport of Sterile Items

Sterile items must be transported in a way that protects package integrity:

  • Use enclosed carts with solid or mesh coverings
  • Avoid overloading carts or stacking heavy items on top of trays
  • Protect from moisture during transport (e.g., outdoor transport between buildings)
  • Keep sterile and contaminated transport carts completely separate — never use the same cart for both without proper decontamination between uses

Common CRCST Exam Questions on Storage & Inventory

Q: What determines whether a sterile item is still considered sterile — time or event?

A: Event. Under event-related sterility, an item remains sterile indefinitely unless an event compromises the packaging.

Q: What inventory rotation method should be used for sterile supplies?

A: FIFO (First In, First Out) — older stock is used before newer stock.

Q: How far off the floor should sterile storage shelving be?

A: At least 8–10 inches, per AAMI guidelines.

Q: What should a technician do if they are unsure whether a package's sterility has been compromised?

A: Treat it as non-sterile and reprocess it — "if in doubt, throw it out."

Frequently Asked Questions

Q: Is event-related sterility used everywhere, or do some facilities still use expiration dates?

A: Most facilities have shifted to event-related sterility per AAMI guidance, but some still apply shelf-life dating for certain packaging types or by facility policy — always follow your department's specific protocol.

Q: Why is this domain worth studying if it's only 9% of the exam?

A: It's one of the most fact-based, memorizable domains — a small, focused study session can lock in nearly all the available points.

Reinforce this domain with our free CRCST practice questions, mapped to all 7 sections of the official HSPA exam content outline.

Official Resources

Topics covered:

sterile storage sterile processingFIFO inventory sterile processingevent-related sterilityCRCST inventory managementsterile storage shelf lifefree CRCST practice questionsfree CRCST practice test

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