Prompts at the Pump: Tips for Behaviorally-Informed Signage

May 28, 2020

Fluctuating gas prices, time spent stuck in traffic, and/or climate concerns can all deter people from driving. However, with so much of our infrastructure geared towards cars, people may need additional motivation to change their driving habits.

Advocates in the U.S., Canada, and Sweden have been working to change consumer behavior around petroleum with a seemingly simple intervention: stickers. Specifically, stickers on gas pumps about the climate impacts of petroleum.

As a result of the advocates’ efforts, Cambridge, Massachusetts, passed an ordinance in late January that all gas station fuel pumps must bear a label that alerts consumers to the climate and health risks of their fuel. Back in 2018, the Swedish Parliament unanimously passed similar legislation to require climate labels at all pumps across the country.

Proponents of these labels have high aspirations for their effects. They “hope that by highlighting the dangers of these fuels at the moment people buy them, the labels will gradually help shift social norms and create demand for more ambitious, far-reaching government action to address climate change.” We thought we’d give this novel gas station strategy a closer look and offer some observations and insights.

In the behavioral science world, we’d call these stickers ‘prompts.’ Prompts are a signal from a given environment at a particular behavioral decision-point that are linked to a motive. The walk/stop signals at crosswalks are a prompt that relies on injunctive norms — norms about what we should and should not do — and the motivation to not get hit by a car to achieve their intended effect. The gas station stickers are therefore a signal in an environment (the gas station) at a particular decision point (buying gas). How they link to motivations will be our focus here.

What’s in a sign?

Why does behaviorally-informed signage matter in the first place? In order to effectively promote a desired behavior, signs need to be designed with that behavior in mind. Though signs can be purely informational, they can also serve as prompts; as mentioned earlier, they can harness social norms or appeal to certain values in order to spur action. The effectiveness of a sign can hinge on how well it uses behavioral strategies. Here is an example to illustrate:

Hotels have a vested interest in guests reusing their towels. Doing so saves the hotel money, with the added benefit of reducing water and energy consumption, which is good for the environment. Of course, guests are generally not invested in saving hotels money, but many are interested in environmental protection. Right?

Bed with rolled towels on it

Researchers at the University of Luxembourg wanted to test what messaging would prompt the highest proportion of guests to reuse their towels. They tried three different messaging strategies. The first focused on environmental protection. The second focused on the behavior of other guests at the hotel with a sign that said that 75% of guests at the hotel usually re-used their towels. The third focused on the behavior of other guests but with a more limited scope, sharing that 75% of guests in that room usually re-used their towels.

The researchers found that appealing to descriptive norms — what other people in the hotel were doing — was more powerful than appealing to environmental values, and that the message highlighting people in the same room was most effective. These findings were consistent with those from an earlier study on the same topic. It turned out that whatever people thought was normal in their environment was more important for their behavior than whether or not they cared about the environment.

Even within a given behavioral strategy, such as norm signaling, how we use that strategy matters for crafting effective signage. Let’s now look at a few key principles of using prompts and their relative effectiveness as applied to the gasoline stickers.

1. Know your audience.

Sweden’s climate labels present facts about the carbon impact of various fuels. Providing information can be a good strategy with a citizen-base that is both familiar with climate change and motivated to act. However, what about citizens not readily able to or invested in translating carbon emissions to climate effects? There is a risk that stickers that are merely educational will have no or a negligible effect, as has been shown for calorie labeling at point of sale. Instead, we might choose to explore our audience’s core values and interests.

A corollary to knowing your audience is choosing the right messenger. For example, if stickers come from the government, depending on a person’s relationship with the government, they could see such stickers as paternalistic and/or overly meddling. The federal or local government might be a trusted messenger in Sweden or Cambridge, but that principle won’t necessarily translate everywhere.

2. Consider your timing.

Though the gas labels have been compared to cigarette labels, the decision conditions at point of purchase are different. As one might expect, you aren’t going to decide not to buy gas if your tank is almost empty just because you see one of these labels. Though the salience and the location of the sticker is the same — reaching the person at their point of decision — the choice environment is not. Because of the limited attention window at the pump, and the difficulty of taking real action in the moment, advocates for stickers need to be quite strategic about what they actually want people to do and whether there will be sufficient motivation to do it.

3. Provide an accessible and explicit call to action.

One of the advocates states that “[the sticker campaign is] more focused on creating a social environment that favors reform and hastening solutions from the government.” Prompts may presume that their viewer understands the details for how to carry out the behavior they are prompting. However, the pathway from seeing the impact of fuel choice to political advocacy is a complex and even abstract one. It relies on the consumer making the connection between product impact and policy, knowing where to plug into advocacy efforts, and being motivated to do so after being away from the pump. Without a more accessible and explicit pathway to action, people may be left simply feeling guilty or disengaged when reminded of their impact.

Here are some ideas for what stickers could share to capture that moment at the pump: contact information for a carpooling program; information about electric and hybrid vehicles vs. gasoline vehicles; or a ‘Did you know?’ message about tax breaks or other policy incentives for oil companies, so people start to make the connection to advocacy. Cities like Cambridge that have electric vehicle charging stations and reliable public transportation could use the opportunity to make explicit mention of those alternatives.

Advocates and legislators making use of prompts are on the leading edge of climate action, and we applaud their efforts. As with many behavior change challenges, there isn’t one right answer here, and success will depend on trial and error. What we can count on is that how and which information is delivered is, in many ways, more important than the information itself.

Of course, climate advocates are dealing with much more than crafting the perfect message. As the efforts of these advocates have shown, it’s hard to get accurate labeling when industry has a vested interest in maintaining the status quo and downplaying the risks of petroleum. Precisely because it is so difficult to achieve even small climate wins, it is doubly important to make sure that they are as effective as possible.

Kate Heller is a past Fellow with Rare’s Center for Behavior & the Environment,