It's a bus shelter ad for the Science World museum in Vancouver, British Columbia, and it looks simple enough. It's a poster featuring a white background and a large yellow circle, with Science World’s familiar blue logo and the words: “Press here and we’ll explain.”

Things get a lot more interesting when the button is pressed.

One first hears the familiar “achoo” sound of a sneeze, then comes a spritz of water to the face.

Then a voice says: “Did you know that a sneeze can travel 12 feet and hover for three hours? It’s true. And gross. But hey, you’ve learned something! Science World – We can explain.”

The thinking behind the campaign was to present funny or outrageous facts and do so in a unique way, says Rob Sweetman, associate creative director and art director at Vancouver’s Rethink Communications, which executed the ad.

The aim: to get people going to the museum to learn more interesting things.

The process that led to the ad began with the interesting facts behind sneezes. From there, the crew at Rethink then brainstormed to come up with a clever way to convey them.

Creating the sound of the sneeze was easy, as was delivering the voice.

The spray of the sneeze? The idea for it came from the sprayer devices seen at fairs or carnivals, which emit mists of water on hot summer days to help cool the crowds. Sweetman says the water in the sprayer is replaced every several days.

The ad will go back up in the spring. It first went up in the fall but was taken down in the fall as the weather turned cold. Quips Sweetman: “We didn’t want anyone freezing their faces.”