We’ve all been told to scrub our hands with hot, soapy water for at least 20 seconds. Need a timer? Hum the "Happy Birthday" song from beginning to end twice.

But why is that?

Science tells us so.

The science behind soap is straight forward, so let's break it down. Soap is made up of molecules that have two sides. One side is drawn to water (called "hydrophilic") and one side absolutely hates water (called "hydrophobic").

When mixing soap and water, the molecules get to work by attacking different sections of whatever is being cleaned; the hydrophobic side runs away from the water and attacks oils and other non-H2O compounds such as fats, while the hydrophilic side clings to the water and helps to rinse away the oils and other unfavorable items. This is why soap and water combined do such a good job at cleaning your dishes.

Eventually after enough time, the soap molecules attach and surround the inner workings of the virus (known as the micelle), and then water is able to wash what is left of the virus away.

Now to the final question: why does this take at least 20 seconds to work?

Simply put, your hand has a lot of cracks and crevices. Viruses thrive on being able to inhabit tiny spaces, which your hands have a lot of.  Washing for 20 seconds gives the soap and water molecules enough time to get into all of the places that you didn’t even know your hand had. Evidence suggests that washing hands for about 15-30 seconds removes more germs from hands than washing for shorter periods.

So how does this relate to UVC disinfection?

The Tru-D technology is also backed by science. Rather than guess or estimate the amount of UVC needed to disinfect a room, Tru-D’s sensors calculate the precise dose needed for thorough room disinfection.

Consider all the variables in a room – the size, shape, contents and the color of the walls that affect reflectivity of the UVC energy. The science behind the Tru-D technology tells us that a measured, calculated dose of UVC energy ensures the cleanest health care environment possible. Much like the science tells us that washing our hands for 15-20 seconds with soapy water ensures that our hands are as clean as possible.

Click here to read more about the Tru-D device’s measured dosing capabilities.