Which option is NOT considered a type of high-level disinfection (HLD)?

High-level disinfection (HLD) refers to processes that eliminate all microorganisms, except large numbers of bacterial spores. Among the options listed, autoclaving is not classified as high-level disinfection but rather as a form of sterilization. Sterilization is a process that completely destroys all forms of microbial life, including spores, and is typically performed using pressurized steam in an autoclave.

Boiling, moist heat, and chemical disinfection are all methods that can achieve high-level disinfection. Boiling is effective for eliminating many pathogens and is often used in resource-limited settings. Moist heat, often in the form of steam, can also effectively kill microorganisms at lower temperatures compared to sterilization. Chemical disinfection employs various chemical agents, such as glutaraldehyde or ortho-phthalaldehyde, that can achieve high-level disinfection depending on the concentration and duration of exposure.

By recognizing that the goal of high-level disinfection is to reduce the number of viable pathogens to a level considered safe for handling, it becomes clear that autoclaving exceeds this level of assurance by achieving total sterility. Hence, autoclaving correctly falls outside the definition of high-level disinfection.