| FAQ - Sterilization - 2014
We are making some changes to the storage cabinets in our sterilization area. As a growing practice we are steadily increasing the number of operative cassettes that we have. We can no longer store all of them in their current cabinets on the holding racks that they are on.
My question is: is there currently a specification for how far apart wrapped cassettes need to be once they are removed from the sterilizer. Not laid on top of one another.
The second question is can they be stored on top of one another? After a certain amount of drying/cooling?
The answer to these questions will help us in figuring out how to arrange our cabinets and storage of sterilized instruments.
Ask OSAP can provide you with some general information on this topic.
Cassettes are perforated metal or plastic/resin containers used to house dental instruments. 1
Contained on the website for the US Centers for Disease Control and Prevention (CDC) is the following information:
Can cassettes be used for sterilizing instruments?
The use of instrument cassettes facilitates instrument processing and can greatly enhance the organization of instruments. It also keeps all the instruments for a specific procedure together from the chairside procedure through cleaning, rinsing, drying, and sterilization. Following completion of dental treatment, instruments can be arranged in the cassette, transported to the instrument processing area, and placed in the ultrasonic cleaner as a unit. The cassette also can be rinsed and dried in this manner. In addition, a cassette system can reduce direct handling of potentially contaminated instruments before sterilization. Furthermore, instruments prearranged in the cassette will require less handling following sterilization.
Different types of cassettes are available. It is important to follow the manufacturer's recommendations for cleaning, wrapping, and sterilizing the cassettes. Perforated cassettes are preferable, since completely solid containers will not allow steam or chemical vapor to reach the contents and allow sterilization to occur. Cassettes can occupy more space than individual packages, so you should consider the size of the sterilizer and amount of storage space available before purchasing any cassette systems.
How should items be stored following sterilization?
Sterile items and disposable (single-use) items should be stored in an enclosed storage area (e.g., cabinet or drawer). Dental supplies and instruments should not be stored under sinks or in other locations where they might become wet. Sterilized items should remain wrapped until they are needed for use.
Unwrapped items are susceptible to contamination. Avoid storing items loose in drawers or cabinets because unwrapped items cannot be kept sterile. Items stored in this manner are subject to contamination from dust, aerosols generated during treatment, and the hands of personnel who must handle them. 2
The 2003 CDC guidelines for infection control in dentistry contains the following general information:
Critical and semicritical instruments that will be stored should be wrapped or placed in containers (e.g., cassettes or organizing trays) designed to maintain sterility during storage (2,247,255–257).
Packaging materials (e.g., wraps or container systems) allow penetration of the sterilization agent and maintain sterility of the processed item after sterilization. Materials for maintaining sterility of instruments during transport and storage include wrapped perforated instrument cassettes, peel pouches of plastic or paper, and sterilization wraps (i.e., woven and nonwoven). Packaging materials should be designed for the type of sterilization process being used (256–259). 3
Storage of Sterilized Items and Clean Dental Supplies
The storage area should contain enclosed storage for sterile items and disposable (single-use) items (173). Storage practices for wrapped sterilized instruments can be either date- or event-related. Packages containing sterile supplies should be inspected before use to verify barrier integrity and dryness. Although some health-care facilities continue to date every sterilized package and use shelf-life practices, other facilities have switched to event-related practices (243). This approach recognizes that the product should remain sterile indefinitely, unless an event causes it to become contaminated (e.g., torn or wet packaging) (284). Even for event-related packaging, minimally, the date of sterilization should be placed on the package, and if multiple sterilizers are used in the facility, the sterilizer used should be indicated on the outside of the packaging material to facilitate the retrieval of processed items in the event of a sterilization failure (247). If packaging is compromised, the instruments should be recleaned, packaged in new wrap, and sterilized again.
Clean supplies and instruments should be stored in closed or covered cabinets, if possible (285). Dental supplies
and instruments should not be stored under sinks or in other locations where they might become wet .3
Additionally, the US Air Force Dental Evaluation & Consultation Service states the following:
Storing Sterile Instruments (6/07)
Question: Can you review the recommendations for storing sterile instruments?
Answer: Instrument processing requires numerous steps, so care must be taken to avoid contamination of the instruments during storage. All sterile supplies and instruments need to be stored in a manner that preserves the integrity of the package. All packages must be examined carefully before use to ensure that the barrier wrap has not been compromised during storage.
+ Allow packages to dry in the sterilizer before handling to avoid contamination.
+ Store sterile items and dental supplies in clean, dry, and dust/lint-free areas with limited access—covered or closed cabinets are recommended.
+ Follow medical treatment facility (MTF) guidelines when storing clean and sterile materials. (In the absence of MTF guidance store clean and sterile materials at least 8 to 10 inches above the floor, 18 inches below the ceiling, and 2 inches from the outside walls.)
+ Keep like items together—sterile with sterile and clean with clean.
+ Implement stock rotation practices (e.g., “first in, first out”) with older items being used first.
- Do not store sterile supplies or patient-care items under the sink (or any location where they may become wet), on the floor, windowsills, or any area other than designated shelving or cabinets.
- Do not store sterile items with items not intended for clinical use such as office or cleaning supplies).
- Do not use shipping cartons to dispense sterile or clean patient treatment items in dental operatories, laboratories, instrument processing, and supply areas.
- Do not handle sterile packages unnecessarily to avoid contamination. 4
These recognized resources provide general information and guidelines regarding sterile instrument storage. Since there are different types of cassettes and requirements may vary, it is recommended that you contact the cassette manufacturer directly regarding more specific guidance and procedures for the storage of their product.
1) American Dental Association. Sterilization and Disinfection of Dental Instruments. https://www.ada.org/members/pdfs/instrument_sterilization.pdf Accessed on March 17, 2014.
2) US Centers for Disease Control and Prevention. Sterilization - Packaging and Storage - FAQs - Infection Control in Dental Settings - Oral Health. http://www.cdc.gov/oralhealth/infectioncontrol/faq/sterilization.htm Accessed on March 17, 2014.
3) Kohn WG, Collins AS, Cleveland JL, Harte JA, Eklund KJ, Malvitz DM, Centers for Disease Control and Prevention (CDC). Guidelines for infection control in dental health-care settings—2003. MMWR Recomm Rep 2003;52(RR-17):1-61. http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5217a1.htm Accessed on March 17, 2014.
4) US Air Force Dental Evaluation & Consultation Service. Sterilization - Packaging and Storage. http://www.afms.af.mil/shared/media/document/AFD-130321-062.pdf Accessed on March 17, 2014.