High-level disinfection (HLD)

Sterile processing definition

High-level disinfection is a process that kills all vegetative microorganisms, mycobacteria, fungi and viruses, but not necessarily large numbers of bacterial spores. It is the minimum processing required for semicritical items such as many flexible endoscopes. HLD uses chemicals like glutaraldehyde, ortho-phthalaldehyde or peracetic acid, at the correct concentration, temperature and contact time.