Spaulding classifications and low-level or high-level disinfection472
| Spaulding classification | Risk of contact | Disinfection | Agents used | Organisms inactivated |
| Non-critical | Only with intact skin | Low-level disinfection (LLD) | Quaternary ammonium compounds, alcohol, phenol | Vegetative bacteria, enveloped viruses, some non-enveloped viruses, fungi |
| Semicritical | With mucous membranes or non-intact skin | High-level disinfection (HLD) | Hydrogen peroxide, peracetic acid, glutaraldehyde, hibidil, hypochlorite | All microorganisms |
| Critical | With sterile tissues | Sterilization | Glutaraldehyde, hydrogen peroxide, peracetic acid, ethylene oxide gas | All viable microorganisms, bacterial spores |