Hand washing: it’s a big deal!

At least that’s what the plethora of multi-step posters want you to believe. And they’re right. We all know that hand washing is one of the most effective ways of preventing illness, but when it comes to the cute stickers proclaiming that “hand washing is only half the battle” we arrive at the classic conundrum. Which one is actually greener, conventional paper towels or hand dryers?

Image by jacqueline macou from Pixabay

It may be tempting to grab a few paper towels

In washrooms across our SFU campus, you’ll without a doubt find paper towel dispensers and Dyson Airblade dryers but does choosing one over the other even matter that much? Surprisingly, yes! Although it may be tempting to grab a few paper towels and save maybe ten seconds of awkwardly passing your hands through a disruptively noisy ultra-rapid hand dryer, the carbon emissions from hand dryers are largely only electricity based, whereas paper towels have a lot more impacts through the production chain.

In a study using Ontario’s energy grid, which is largely composed of nuclear and hydroelectricity, paper towels released 162% more carbon dioxide than your regular hand dryer (Joseph, Baah, Jahanfar, & Dubey, 2015, 5. Interpretation). In Metro Vancouver, where 95% of our electricity comes from hydroelectricity (Clean Energy BC, 2018), and on campus, where most hand dryers are ultra-rapid and more efficient, you can expect a much larger reduction in carbon emissions by leaving the paper in its place.

Do paper towels have any redeeming qualities at all?

Yes, slightly, in terms of hygiene. Although both paper towels and hand dryers produce microscopic water droplets that can facilitate the spread of droplets, paper towels did, in fact, localize the spread of droplets a bit better than air dryers (Margas, Maguire, Berland, Welander, & Holah, 2013, Discussion).

So, which should you use? It appears that most hurried students on campus are opting for a few paper towels, especially during peak times between classes. But if you can spare the extra bit of patience and bear a little noise, the ultra-rapid hand dryers look like your best bet in terms of environmental impact. Should SFU completely eliminate paper towels? I think we should try! Tossing the towels in high-traffic washrooms would help decrease carbon emissions! And it would probably save the school money they can put towards getting more therapy dogs.

Whichever hand-drying way you choose, at least you’re drying them! Drying your hands can reduce bacteria from moist hands to other surfaces by 99% (Patrick, D. R., Findon, G., & Miller, T. E., 1997, Abstract). But God forbid if you stumble upon an ancient conventional warm-air dryer.

References

Clean Energy BC. (2018). Large Hydro. Retrieved from https://www.cleanenergybc.org/about/clean-energy-sectors/large-hydro

Joseph, Baah, Jahanfar, & Dubey. (2015). A comparative life cycle assessment of conventional hand dryer and

roll paper towel as hand drying methods. Science of the Total Environment, 515-516, 109-117.

Margas, Maguire, Berland, Welander, & Holah. (2013). Assessment of the environmental microbiological cross

contamination following hand drying with paper hand towels or an air blade dryer. Journal of Applied Microbiology, 115(2), 572-82.

Patrick, D. R., Findon, G., & Miller, T. E. (1997). Residual moisture determines the level of

touch-contact-associated bacterial transfer following hand washing. Epidemiology and infection, 119(3), 319-25.