ARRT Patient Care Practice Exam

What is considered the most effective method of sterilization?

1. Dry heat

2. Moist heat

3. Pasteurization

4. Freezing

The correct answer is: Pasteurization

The most effective method of sterilization is moist heat, specifically through the use of steam under pressure, such as in an autoclave. This method is known to effectively kill all forms of microbial life, including spores that are resistant to other forms of sterilization. The reason moist heat is effective lies in its ability to penetrate materials and transfer heat more efficiently than dry heat. The high temperatures achieved in an autoclave make it capable of achieving sterilization in a much shorter time than dry heat methods. Though pasteurization is an effective process for reducing the number of viable pathogens in food and beverages, it does not achieve complete sterilization. Instead, it aims to eliminate specific harmful microorganisms while preserving the overall quality of the product. Therefore, while pasteurization is important for food safety, it is not considered a method for achieving true sterilization. Dry heat is effective for certain materials and can be used for sterilization, but it generally requires longer exposure times and higher temperatures to achieve the same level of microbial kill as moist heat. Freezing does not sterilize items; instead, it tends to inhibit microbial growth. Microrganisms can survive freezing temperatures and may become active again once thawed. Thus, moist heat stands out as the