The Science Behind Hand Sanitizers: How They Work and When to Use Themby John Picco
The Science of Hand Sanitizers
Hand sanitizers are designed to kill or deactivate harmful microorganisms on our hands, including bacteria and viruses. Their effectiveness is attributed to their active ingredients, which typically fall into two categories: alcohol-based and non-alcohol-based sanitizers.
Alcohol-Based Hand Sanitizers
Alcohol-based hand sanitizers are the most common and widely recommended type. They typically contain ethanol (ethyl alcohol), isopropanol (isopropyl alcohol), or a combination of both. These alcohols work by denaturing proteins and disrupting the lipid (fatty) membranes of microorganisms.
When you apply an alcohol-based sanitizer to your hands and rub them together, the alcohol molecules penetrate the cell walls of bacteria and envelop viruses, effectively killing them. This mechanism of action makes alcohol-based sanitizers highly effective against a broad spectrum of pathogens.
Non-Alcohol-Based Hand Sanitizers
Non-alcohol-based sanitizers, often using active ingredients like benzalkonium chloride or triclosan, work differently. They typically take longer to act and may not be as effective against certain viruses as alcohol-based sanitizers. However, they can still provide some level of protection when soap and water are not readily available.
When and How to Use Hand Sanitizers
Frequency: Use hand sanitizers when soap and water are not accessible, but do not replace regular handwashing with sanitizer. Frequent handwashing is essential, especially before eating, after using the restroom, and after touching surfaces in public places.
Proper Application: Apply a sufficient amount of sanitizer (at least a quarter-sized dollop) to cover both hands entirely.
Rub Thoroughly: Rub your hands together vigorously, making sure to cover all surfaces, including the backs of your hands, between your fingers, and under your nails. Continue rubbing until the sanitizer is dry, which typically takes about 20 seconds.
Avoid Towel Drying: Do not wipe or rinse your hands after applying sanitizer; let them air dry naturally.
Children: Supervise young children when using hand sanitizer to ensure they apply it correctly and avoid ingesting it.
Safety Precautions: Keep hand sanitizers out of reach of young children, as ingestion can be harmful. Also, avoid using hand sanitizers if your hands are visibly dirty, as they may not be as effective in such cases.
Hand sanitizers play a crucial role in maintaining hand hygiene, especially in situations where handwashing facilities are not readily available. Understanding the science behind their effectiveness and following proper usage guidelines is vital for protecting yourself and others from harmful microorganisms. Remember, while hand sanitizers are a valuable tool, they should complement, not replace, regular handwashing with soap and water for thorough hand hygiene.