- Certified Medical Device Reprocessing Technician Low-Temperature Sterilization Questions and Answers Flashcards

What is vaporized hydrogen peroxide (VHP) sterilization and how does it differ from hydrogen peroxide gas plasma?

Answer: VHP sterilization uses hydrogen peroxide in vapour form without the plasma phase, operating at lower concentrations and temperatures with different cycle parameters

VHP sterilization (such as the V-PRO system) generates hydrogen peroxide vapour that sterilizes devices without the plasma phase used in STERRAD systems. It operates at different parameters and may have different material compatibility profiles.

What is the role of humidity in ethylene oxide sterilization?

Answer: Adequate humidity (typically 40-80% RH) is essential because moisture hydrates bacterial spores, making them more susceptible to ETO penetration and killing

Bacterial spores in a desiccated (dried) state are more resistant to ETO. Humidity during the preconditioning and exposure phases rehydrates spores, allowing ETO gas to penetrate and alkylate the DNA and proteins, achieving microbial kill.

What packaging materials are acceptable for hydrogen peroxide gas plasma sterilization?

Answer: Non-cellulose packaging such as polypropylene (Tyvek) pouches and non-woven polypropylene wraps specifically validated for the sterilizer

Because cellulose absorbs hydrogen peroxide and interferes with the sterilization process, only non-cellulose packaging materials validated by the sterilizer manufacturer can be used. This typically means Tyvek or polypropylene-based materials.

How often must biological indicators be used for low-temperature sterilization methods?

Answer: With every sterilization load, as recommended by CSA Z314.3 for ETO and hydrogen peroxide sterilization systems

CSA Z314.3 recommends biological indicators be used with every load for low-temperature sterilization methods because these methods have more variables that can affect efficacy compared to well-established steam sterilization.

What is the ozone sterilization method and what are its advantages?

Answer: A low-temperature sterilization method using ozone gas (O3) that decomposes to oxygen, leaving no toxic residues on processed devices

Ozone sterilization (such as the TSO3 system, developed in Canada) uses ozone gas at low temperatures. Its main advantage is that ozone naturally decomposes to oxygen, eliminating the need for aeration and leaving no toxic residues on devices.

What should a CMDRT professional verify before loading devices into a low-temperature sterilizer?

Answer: That each device is compatible with the specific sterilization method, is thoroughly cleaned and dry, is in correct packaging, and all lumens meet the sterilizer's specifications

Verifying device compatibility, cleanliness, dryness, proper packaging, and lumen specifications before loading prevents sterilization failures, device damage, and patient safety incidents.