What is the primary requirement for hand sanitizer to be effective?

The primary requirement for hand sanitizer to be effective is that it must be alcohol-based. The active ingredients in alcohol-based hand sanitizers, such as ethanol or isopropyl alcohol, are proven to be effective at killing a broad spectrum of pathogens, including bacteria and viruses. The Centers for Disease Control and Prevention (CDC) recommend using hand sanitizers that contain at least 60% alcohol for optimal efficacy.

Other formulations, such as foam or gel-based, can be effective as long as they contain the required concentration of alcohol. While some hand sanitizers may claim to be antibacterial, not all germs are bacteria, so relying solely on antibacterial properties does not ensure broad-spectrum pathogen effectiveness. Thus, the key factor lies in the alcohol content rather than the specific formulation type or additional antibacterial claims.