Wednesday, November 5, 2008

I've been wrong this whole time

For years I told people I know not to use hand dryers in public washrooms because Joe Bob's uncles brothers sister-in-laws pastors scientist brother told him about a study in the Journal of Urban Legends that hand dryers actually increase bacterial counts on skin after hand washing. Today, while vigorously washing my hands after doing a onesie, I contemplated two questions on this issue:
1. What method of drying hands is more hygienic: hand dryer or paper towel?
2. What method of drying hands is more environmentally friendly: hand dryer or paper towel?

Surely no one has pondered such obscure questions before. Wrong again.

First wrong: hygiene question. A study out of the Mayo Clinic compared 4 hand drying methods and how they affected bacterial cell counts on participants hands after washing with soap. Paper towel, forced hot air, something called spontaneous room air evaporation (cool; can you still breathe?), and some other method that I can't remember all produced similar results. Verdict: Urban legend sucks. Verdict #2: Touching paper towel dispensers makes me icky, so I will continue to bodycheck the hand dryer to turn it on, thereby preventing transfer of icky bugs to my hands.

Second wrong: Many people ask obscure questions such as these. Not only did a respected organization like the Mayo Clinic conduct a randomized trial like the one above, but many have studied my second question: the environmental impact of each drying method. Turns out the hand dryer wins....hands down. Ouch. Dicey pun. The life cycle carbon impact of hand dryers is much lower. Over its life it emits something like 1.5 tonnes of carbon dioxide through the production of energy necessary to power it. The paper towels on the other hand release 4.5 tonnes of carbon dioxide due to the loss of trees (effective carbon sinks) and the production methods used to create them.

So I will now vehemently promote the use of hand dryers. But you must use bodychecking. It works great and really creeps out your fellow bathroom inhabitants.

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