Washing your hands with cooler water can be better for the environment

Have you ever been told that it’s better to wash your hands with hot water? According to a recent study conducted by researchers at Vanderbilt University, using clean running water at a cooler temperature can be just as effective — and it can be better for the environment, too.
 
While it’s true that heat kills bacteria, the temperature needed to kill germs on your hands could burn you. That means that there may be no real benefit to washing your hands with hot water. In fact, using a really high temperature can irritate your skin, which can make bacteria stay on your hands.
 
So why do folks use hot water if it’s not killing germs? One reason is that many hand soaps tend to work better with warmer water. Another reason may be that they’ve always done it that way and just don’t know any better!

 

So how does using cooler water help the environment, you may ask? The fact is that heating water takes energy. Creating energy — such as through burning fossil fuels like such as coal, natural gas and oil — can lead to the release of gases that trap heat in the atmosphere, known as greenhouse gases. Increasing levels of greenhouse gases raise global temperatures leading to climate change.

 

So does that mean you should only use really, really cold water to wash your hands? That might not be a good idea either. It takes awhile to wash your hands properly, and that’s hard to do when the water is freezing cold. Your best bet is to pick a temperature somewhere in the middle that feels comfortable to you.

 

The key thing is to make sure that you’re washing your hands properly. This means that you are scrubbing, rinsing and drying your hands several times a day, particularly before eating and after using the bathroom. Here are some tips, courtesy of the Centers for Disease Control and Prevention:

• Wet your hands with running water. Remember to immediately turn off the tap to make sure you’re not wasting water.
• Apply soap and rub your hands together. Make sure to clean the back of your hands, under your nails and between your fingers, and continue rubbing your hands for at least 20 seconds.
• Rinse your hands well under clean, running water.
• Dry your hands using a clean towel or air dry them.

For more tips, check out our Get Ready hand-washing page, which features fact sheets in both English and Spanish.