Soaps… What Does 99.9% Really Mean?

by Yang Lu

Currently, the World Health Association lists washing hands as a primary preventative against the spread of Covid-19. This puts greater importance onto the soaps we use every day. You may also have noticed that these soaps always have a little label advertising its effectiveness against 99.9% of germs. But what does 99.9% really mean? And do soaps truly help prevent you from catching Covid-19?

How does soap work?

A germ is any microscopic particle that can make people sick. Germs include bacteria and viruses, like Covid-19. Whenever we touch a surface, millions of germs stick onto our hands through the oil on our skin. To get rid of these sickness causing particles, we use soap. Soap is a long chain of carbon and hydrogen atoms that has two ends. One end of soap, called the hydrophilic end, attaches to a water molecule, and the other end, called the hydrophobic end, attaches to oil. When you use soap, it binds water to oil, which contains the germs, to all be washed together down the sink.

99.9%… With a Catch.

Soaps can kill 99.9% of germs. Under perfect conditions. And in a lab. These numbers come from tests that place bacteria on a clean surface, wipe down that surface with the soap, then measures the number of bacteria left over. However, this isn’t at all an accurate representation of real-life. Studies have shown that this number is closer to 92% with actual use.

A Useful Weapon Against Covid-19?

Authorities are currently trying to slow down the infection rate in which Covid-19 is spreading because there is no vaccine. Washing hands has been proven to be an effective solution, reducing the risk of contracting a respiratory illness by 54%.

Washing your hands with soap is an important ritual that prevents the spread of diseases such as Covid-19. Whenever you sneeze or simply touch your phone, just to be safe, give your hands a quick clean.

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