Scentrees

Interactive installation to train people’s senses to detect changes in air quality

— Project Overview

Can we train our senses to detect changes in air quality?

Maybe we can only smell what we’ve smelled before? Can we design a series of reference smells that help people tease out the various smells that might be associated with changing air qualities? How can you experience ranges of air quality through scents?

AQI, a quantitative measure of air quality, is yet another data point to add to the heap of climate data we are meant to track in our minds. In this project, we explore ways to engage the human sense of smell in the process of better understanding AQI and changes in the environment.

— Problem

What is AQI 61?

According to AirNow.gov, AQI “tells you how clean or polluted your air is, and what associated health effects might be a concern for you.” While mostly background data rounding out a table of current conditions in a weather app, the consequences of shifting AQI become apparent when “sensitive groups” are politely encouraged to “limit prolonged exposure” or when the stench of rotten eggs creeps through the city.

The AQI’s ability to impart any practical knowledge of how and why these changes occur is as fleeting as the indicator itself. Indeed, we’re not quite sure what AQI 61 is, but sometimes it smells like eggs. Here begins our inquiry: Is it possible to tune our sense of smell to practice a sensuous way of knowing—creating an embodied and intuitive way of accessing data about the quality of the air we breathe?

— Research

How can we deliver?

How can we create scents representing air pollutants?

The human nose becomes numb to scent in as little as two breaths. This phenomenon, nose blindness, is helpful in identifying sharp changes in smell that might signify environmental danger, but helpless in our recruitment of the nose as a persistent environmental sensor. Borrowing from the practices of sommeliers and perfumers, we recreated the scents associated with the five major air pollutants for which AQI accounts: groundlevel ozone, particle pollution (PM10 and PM2.5), carbon monoxide, sulfur dioxide, and nitrogen dioxide.

Scentrees

The experience of our research tool begins with the diffusion of these scents disguised amongst the leaves on the branch of a tree. Circulating air (or a fan) carries the noticeable scents toward idle noses. A closer inspection of the tree reveals their origin along with information about what kind of air is associated with this scent. Participants can take the perfume card with them for further inspection or as a sample “reference smell”. After identifying the scent, participants can match it to a postcard which contains more information about the source of the smell.

Unlike the quick whiff of some unidentifiable odor in everyday life, here the smell, its associated AQI, and its place or mechanism of origin persist. Nose blindness is no match for the high availability and portability of AQI’s “reference smells.” After engaging with the diffuser, participants are asked to reflect on their thoughts and feelings. All materials can also be collected and taken home by participants.