Earlier this year, the U.S. Environmental Protection Agency started a program to reduce hotel water consumption called the H2Otel Challenge. In addition to installing new equipment, such as water-efficient toilets, faucets, and shower heads, hotels are encouraged to give guests the option of reusing their towels and sheets with those little signs that have become ubiquitous across the United States. You know, the ones that look like this:
What the EPA doesn't mention (at least in its factsheets available online) is that the wording used in designing these signs matters—a lot. Signs that draw on our concern for the environment, as the above one does, are good motivators. But new and old evidence alike suggests that signs drawing on our sense of social norms, telling us just how many other people in our same position reused a towel or a linen, are better ones.
The instant-classic study on the subject appeared in a 2008 issue of the Journal of Consumer Research. Knowing the basic power of social norms, behavioral scientists Noah Goldstein, Robert Cialdini, and Vladas Griskevicius created two versions of the towel re-use signs for guests. One gave the standard industry message playing on environmental concerns. It said this:
"HELP SAVE THE ENVIRONMENT. You can show your respect for nature and help save the environment by reusing your towels during your stay."
The other focused on social norms:
"JOIN YOUR FELLOW GUESTS IN HELPING TO SAVE THE ENVIRONMENT. Almost 75% of guests who are asked to participate in our new resource savings program do help by using their towels more than once. You can join your fellow guests in this program to help save the environment by reusing your towels during your stay."
Over the next 80 days, with the help of staff at a national hotel chain, the researchers collected data on whether or not guests reused at least one of their towels. They found that guests with the social norm sign reused their towels at a significantly higher rate than those with the standard sign (chart, below). In a second experiment over 53 days, the researchers found that signs referring to guests in that specific room number—as opposed to just other hotel guests in general—served as even stronger motivators for towel reuse.
So reminding people to save the environment by reusing their towels was effective, but it wasn't as effective as telling them that other guests in the hotel reused their towels, and neither approach was as effective as telling them that other guests in that exact room reused their towels. The point is that not all forms of persuasion are created equal. For a number of possible reasons—peer pressure, perhaps, or even the minor kinship that forms among hotel patrons—guests reused towels when they knew that other guests in their position did the same.
New evidence suggests Americans aren't the only ones susceptible to the slight change in wording. Earlier this year, a research group out of the University of Luxembourg replicated the study over a six-week period at alpine resorts in Central Europe. Once again, guests whose signs mentioned a specific room used fewer towels than guests whose signs mentioned the hotel at large, who in turn used fewer towels than guests whose signs used the standard approach of environmental awareness.
But it's too soon to call the finding universal. In yet another study, also published this year, researchers at the University of Bielefeld failed to replicate the study in guests at German hotels—with the standard message being most effective in this setting. Noah Goldstein, who was part of the original 2008 study, says the standard reuse signs in Germany included an extra line that might have served as a subtle social norm in its own right: "Every day we clean a great number of towels, many of them are unused." Additionally, the 75% compliance figure might have seemed low to Germans, and might have produced unexpected effects as a result.
"So it's possible that the descriptive norm worked in the opposite direction," Goldstein, a UCLA professor and coauthor of The Small Big: Small Changes That Spark Big Influence, tells Co.Design. "Something akin to, 'Wow, I didn't realize so few of my peers are reusing their towels, so maybe I don't need to, either.'"
As far as American hotels are concerned, Goldstein says he knows of "a few" that have adopted social norm messaging since the initial research emerged. At least two—the Westward Look in Tucson and the Wit in Chicago (sign below)—have gone the ultimate step and mentioned the behavior of guests who stayed in the same room. The EPA could no doubt spread awareness of this highly cost-effective water-conservation strategy by informing hotels of the research in its H2Otel Challenge material.
And if the agency has any trouble persuading hotels to use social norm signs, it could always try mentioning how many others in the same position already do.