Ever walk into a public bathroom where the lights were turned off? This experience might have caught you off guard, but do you think that it had any influence on whether or not you turned off the lights yourself when you left the bathroom?
My colleagues Patrick Dwyer, Alexander Rothman, and I recently had an article published in the Journal of Environmental Psychology (the article can be accessed for free until January 17, 2015, at the following link) exploring this very dynamic in public bathrooms. Specifically, across two experimental studies conducted using actual public bathrooms, we explored who is more or less likely to turns off the lights in public bathrooms.
In the first study, we simply randomized whether lights were on or off before people used a public bathroom, without their knowledge as to their involvement in an experiment. We did this for both women’s and men’s bathrooms, and multiple user bathrooms (such as the picture below, where more than one person could enter the bathroom at a given time) and single user bathrooms (where only one person uses the bathroom, and the person has the ability to lock the door).
In this first study we found a huge difference in whether or not people turned off the lights after using the bathroom according to whether the lights were on or off when they first entered. For those individuals who entered the bathroom when the lights were on, only 12% of people turned off the lights. However, for those individuals who entered the bathroom when the lights were off, 32% of people turned off the lights. This means that walking into the bathroom when the lights are off makes it almost three times more likely that you will turn off the lights when leaving the bathroom!
We also found that, collapsing across experimental conditions, women were much more likely to turn off the lights when exiting the bathroom compared to men (31% of women’s bathroom users versus 10% of men’s bathroom users), and people in the single user bathrooms were much more likely to turn off the lights when exiting compared to people in the multiple user bathrooms (43% in single user versus 9% in multiple user).
What about the differences between women’s and men’s bathroom users? Well, prior research does suggest that, on average, women are more likely to engage in behaviors that are positive for the environment. What about the difference between single and multiple user bathrooms? Probably part of what is happening there is that people might be unsure whether someone else is going to soon walk into the multiple user bathroom, and they may even be uncertain whether someone else is also using that multiple user bathroom at that time. Although we were careful to exclude data from any instances where someone else walked into the bathroom when a primary person was already using it, people in the study were unaware that they were in the study, and thus might have wanted to avoid turning the lights off on someone who was also using the bathroom (that sure would be awkward!).
The single versus multiple user results also pointed toward another option: people might feel more responsible for the light status when they are using a single user bathroom, since nobody else could have possibly been using the lights at the same time. One model of prosocial behavior, called the Norm Activation Model, posits that social norms are particularly likely to lead to positive behavior when people also feel responsible for the relevant issue or behavior. So the social norm that people turn off the lights in a given bathroom, combined with the feeling of personal responsibility that you have to be the one to turn off the lights, might be a particularly potent combination that can lead to greater amounts of energy conservation in public bathrooms. We set out to test this possibility in a follow-up experiment.
What we found was that there was not a significant difference between the condition where the lights were on (the same “lights on” condition in the first study) and the new condition where the confederate turned the lights off then on (39% in the off condition and 29% in the new “off then on” condition*). However, the “lights off” condition from the first study, where people simply entered the bathroom when the lights were off, led to a whopping 74% of people turning off the lights in this study.
What is the takeaway message from all of this?
This research provides evidence (and extends previous research on the topic) that it is this combination of social norms and personal responsibility that is most effective at eliciting energy conservation in public spaces, including public bathrooms. It is interesting to note that we did not find significant differences between women and men in the second study, although the trend was in the same direction as the first study (49% of women turned off the lights in the second study, as compared to 35% of men).
However, the social sciences are complex, and additional questions always remain. What exactly is it about turning on the lights yourself when you enter the bathroom that leads to such drastic increases in the chances that you will turn off the lights when you leave? Is it just feelings of personal responsibility, or does it also increase memory or knowledge for where the light switch is located? Can we leverage the use of common message prompts to turn off the lights in public bathrooms to do a better job of eliciting perceptions of social norms and feelings of personal responsibility? And how does the fact that many public bathrooms are switching to automatic, timed lights going to affect energy conservation in public bathrooms?
What do you think?
* Although there is obviously a 10% difference between these two conditions, our confidence in stating that the two experimental conditions are likely different on some outcome, which here would be percentage of people turning off the lights when exiting the bathroom, is partially reliant on how large our sample of people in the study is. Think of it like sampling error in political polling – the more people we have in a political poll, the more confident we can be that Candidate A is truly favored over Candidate B.
So, given the sample size, we cannot be reasonably confident that these two conditions led to real differences in how frequently people turn off the lights when exiting the bathroom.