Bigger signs are more effective at prompting people to turn off washroom lights

Simple, well-designed signs can be effective at prompting people to turn off washroom lights. Bigger signs are more effective than smaller signs.

Using seventeen washrooms across five buildings on a university campus, the authors tested the effectiveness of two different sized signs at prompting users to turn the lights off when they were not in use. The authors tested two different sizes of the sign over 43 days via a process of:

1. Measuring the baseline – i.e. recording ‘lights off’ behaviour before placement of a sign in the washrooms
2. Applying the intervention – i.e. measuring ‘lights off’ behaviour once the signs were placed in the washrooms
3. Removal of the intervention – i.e. recording ‘lights off’ behaviour when the signs were subsequently removed
4. Re-introduction of the intervention – i.e. measuring ‘lights off’ behaviour once the signs were re-installed.

The authors found that the presence of a sign did make a difference – a small sign was six times as effective than no sign at prompting ‘lights off’ behaviour, and that large signs were almost twice as effective as small signs.

From this, our take home points for conservation researchers and practitioners are:

• Well placed, well designed signs can be effective at prompting desirable behaviour
• This will be more effective where behaviours are more convenient to undertake, and
• Bigger signs can be more effective when they help increase the salience of the message.

It should also be noted that the authors put much thought into the design of their sign – please read this paper before you make your own signs.

Sussman R., & Gifford R., (2011). Please turn off the lights: The effectiveness of visual prompts. Applied Ergonomics 43(3), 596-603