Final answer:
Alcohol-based hand sanitizers are suitable when soap and water are unavailable and hands are not visibly dirty, with sanitizers containing 60% to 80% ethanol or isopropyl alcohol being most effective. Care should be taken due to their volatile and flammable nature.
Step-by-step explanation:
Alcohol-based hand sanitizers are suitable under certain circumstances where traditional handwashing with soap and water is not available. They work effectively by denaturing proteins and disrupting microbial cell membranes. However, alcohols are not effective in the presence of visible dirt, as they cannot penetrate the grime. Therefore, sanitizers should be used on hands that are not visibly dirty or greasy.
The Centers for Disease Control and Prevention (CDC) recommends using a hand sanitizer with at least 60% ethanol or isopropanol alcohol concentration. The efficacy of these sanitizers is maximized when the hands are covered completely with the sanitizer and allowed to air dry without wiping. Since ethanol is volatile and flammable, care should be taken when using sanitizers with this active ingredient.
It's also crucial to consider skin care when using alcohol-based sanitizers frequently, as they can cause skin dehydration. Many sanitizers contain moisturizing agents like ethylene or glycerin to help keep the skin soft. Overall, alcohol-based sanitizers are a quick and effective method to reduce microbes on the skin, specifically when soap and water are not readily accessible.