Medical Device Reprocessing Association of Ontario (MDRAO) Practice Exam

What is the primary function of irradiation sterilization?

1. To remove all moisture from instruments

2. To create mutations in DNA of microorganisms

3. To heat objects to high temperatures

4. To separate harmful chemicals from devices

The correct answer is: To create mutations in DNA of microorganisms

Irradiation sterilization primarily functions by creating mutations in the DNA of microorganisms, which leads to their inactivation or death. This process utilizes high-energy radiation, such as gamma rays, electron beams, or X-rays, to disrupt the molecular structure of the DNA within the organisms. By causing damage to the DNA, the radiation effectively prevents the microorganisms from reproducing and carrying out their vital functions, ensuring that the instruments are rendered sterile. This method is particularly valuable in medical contexts because of its effectiveness at penetrating materials and its ability to sterilize a wide range of devices without requiring high temperatures or moisture, making it suitable for heat-sensitive items. The other choices involve processes that do not accurately reflect the purpose of irradiation sterilization; for instance, while removing moisture might be an aspect of other sterilization processes, it is not the main function of irradiation. Similarly, heating objects to high temperatures pertains more to steam sterilization or dry heat methods, and separating harmful chemicals does not align with the bactericidal properties of irradiation.