Assistant Laboratory Animal Technician (ALAT) Practice Exam

What type of sterilization method uses superheated steam and pressure?

1. Dry heat sterilization

2. Liquid chemical sterilization

3. Autoclaving

4. Radiation sterilization

The correct answer is: Autoclaving

Autoclaving is a sterilization method that utilizes superheated steam under pressure to effectively kill microorganisms, including bacteria, viruses, and spores. The process typically operates at a temperature of around 121-134 degrees Celsius and requires both heat and moisture to achieve high levels of sterilization. The pressure helps to elevate the boiling point of water, allowing for steam to reach and maintain the necessary temperatures for effective sterilization. This method is widely used in laboratories and medical settings because it ensures thorough sterilization of instruments and materials, including those that are heat-sensitive, when used appropriately. In contrast, dry heat sterilization employs hot air to sterilize materials without moisture, which can be effective but generally requires longer exposure times and higher temperatures. Liquid chemical sterilization utilizes chemical agents for sterilization but may not provide the same level of assurance as autoclaving in all instances. Radiation sterilization involves using ionizing radiation, such as gamma rays, to eliminate microorganisms but does not rely on steam or pressure, making it a different process altogether.