How soap and water works

Washing with soap and running water does two things at once: it disrupts the bonds that allow microbes and oils to cling to skin, and the mechanical action of scrubbing and rinsing physically removes dirt, debris and germs. Soap molecules bind to oils and trapped microbes; when you rinse, those particles wash away. Because of this physical removal, soap and water is especially effective when hands are visibly dirty, greasy, or contaminated.

Correct technique for best results

1. Wet hands with clean running water.
2. Apply soap and lather thoroughly — backs, between fingers, under nails.
3. Scrub for at least 20 seconds (sing “Happy Birthday” twice as a timer).
4. Rinse well and dry with a clean towel or air dry.

How hand sanitizer works

Alcohol-based hand sanitizers (the ones you commonly see) work by inactivating many bacteria and viruses on contact. They are convenient, portable, and fast — making them a valuable tool for situations where sinks are not available. The key is alcohol concentration: a sanitizer should contain at least 60% alcohol to be reliably effective.

Limitations to remember

• Sanitizers do not physically remove dirt, grease, or chemicals.
• If hands are visibly soiled or greasy, sanitizer may not work well.
• Proper use matters: apply enough product to cover all surfaces and rub until dry.

When to use each — practical guidance

Think of soap and water as the gold standard and hand sanitizer as a strong backup. Use the method that fits the situation:

• Use soap and water when: your hands are visibly dirty or greasy (after cooking, gardening, handling raw food), after using the toilet, or after exposure to hazardous materials or bodily fluids.
• Use hand sanitizer when: you’re on the go and don’t have access to a sink, your hands are not visibly soiled, and you need a quick, effective reduction of germs.

Evidence and real-world notes

Research consistently shows both methods reduce infections, but soap-and-water tends to remove more types of contaminants because it physically washes them away. For certain hardy pathogens and for situations involving heavy soil or grease, handwashing is superior. For routine, quick hygiene in public or while traveling, alcohol-based sanitizer (≥60% alcohol) provides practical protection.

Practical tips for better hand hygiene

• Carry a 60%+ alcohol hand sanitizer for when you can’t reach a sink.
• When using sanitizer, apply enough to cover all hand surfaces and rub until dry — don’t wipe it off prematurely.
• Moisturise regularly: frequent washing or sanitizer use can dry skin, which may lead to cracks and higher infection risk.
• Teach children proper technique — lathering time and full coverage matter.
• Keep fingernails short and clean; microbes hide under nails.

Common myths — quick clarifications

• Myth: “Sanitizer is always better.” Fact: Not true — sanitizer is convenient, but soap & water is better when hands are visibly dirty.
• Myth: “Any sanitizer works.” Fact: No — sanitizers under ~60% alcohol are much less reliable.
• Myth: “If I sanitize, I never need to wash.” Fact: Sanitizer is a backup; washing is still required for many situations.

Conclusion

Hand hygiene is simple but powerful. Prioritise soap and water whenever you can, especially when hands are dirty or after high-risk tasks. Carry a quality alcohol-based sanitizer for times when washing isn’t possible. Using the right method, at the right time, with correct technique will keep your hands cleaner and reduce the spread of infections.