Video tool

Type of tool: Pop-up

Phase: Deployment


How to collaboratively measure exposure in a neighborhood

People involved:





Utrecht University

The Challenge

Imagine you want to know the best places to measure exposures in a neighbourhood.  For this activity you will need to use portable devices or sensors that can fit into a backpack. The equipment will depend on the exposure you wish to characterize.

How is exposure data collected through sensory walks?

The Tool

During a workshop with citizens you discuss areas in which citizens are often exposed to the exposure of interest/ areas in which they expect the exposure to be. Together, citizens and researchers, they develop one or multiple sensory walking routes. Once these sensory walks have been developed participants and researchers can collect data on the environmental exposure throughout the route. This is done by walking the predetermined route until you are in the presence of this exposure. Once the exposure has been identified for example through smell, sight or hearing, participants are requested to stop walking and try to “catch the exposure” as best they can for 2 minutes. After two minutes the participant continues with their walk until they identify the exposure of interest again. Depending on the environmental exposure we aim to monitor, citizens will use different methods and equipment to collect data. Sensory walks can also be used to calibrate the equipment or train citizens in in-situ data collection, in order to ensure good data quality. Below we describe a case of collecting data on woodsmoke through the use of sensory backpacks that contained an Aethalometer (MA200), a SidePak (AM520), a DiscMini and a GPS logger (Q1000XT or GT-750).

Discover the tool in action!

Read the case study and understand how this tool has been used in a real citizen science project.

Sensory walks to smell woodsmoke

Cities-Health Utrecht pilot


A sensory walk was conducted in the Cities-Health Utrecht pilot to collect information about woodsmoke in IJburg, Amsterdam. Citizens have an in-depth knowledge of areas where one could often smell woodsmoke in their neighbourhoods. Their expertise helped determine the ideal route for exposure data collection. When sensory walks are done by citizens with a researcher present, researchers can learn a lot with regards to how citizens collect data and correct any collection errors to ensure data quality. Citizens in turn were also able to ask researchers questions and share insights with one another throughout the sensory walks.


To gather exposure data at points where the exposure is present for example the smell of woodsmoke in an air pollution sensory walk, or noise in a noise pollution sensory walk.
To ensure data quality for both citizens and researchers.
To ensure the equipment is correctly calibrated.
To troubleshoot any data collection issues.
To allow citizens to ask questions and share insights (with both researchers and other citizens).
Foster a civic research community

Design the route with citizens. Citizens affected by an environmental problem often have deep knowledge of the affected area. It is therefore crucial to include their situated knowledge when designing the route of the sensory walk. To this end, we had a design workshop with citizens where we asked them to indicate all the areas on a map where woodsmoke was frequently present.
Test the route through a trial walk. It might be a good idea to do a trial before conducting the sensory walk with the entire group of participants. This will allow you to detect any issues, such as the total length, effectiveness of equipment calibration purposes, etc. You can do this trial with a couple of participants or do this on your own. In our case, this walk was conducted by two researchers to make sure there was a central starting point which was easy to find and where our research equipment could be calibrated, make sure the walk did not take longer than 2 hours and that woodsmoke was present throughout the predetermined routes.
Sensory walk with citizens. Together with all of the interested citizens we conducted the sensory walk. Throughout this walk researchers were able to troubleshoot any data collection issues (such as not standing still when trying to measure the exposure or not writing down the time when a “measuring stop” took place) and train all of the citizens at the same time. Sharing of data between researchers and citizens occurred in the presence of all interested parties.