These general assessments remind us of the context within which Cairgo Bike activity was developed. The core business of the project to mobilise behaviour change, centres around the communication element of the project and the programmed participation in testing and training activities:
- raising awareness, encouraging people to understand how their mobility choices influence their exposure to pollutants;
- explaining the opportunities offered by the project, and;
- targeting and mobilising citizens (families) and professionals to convert to cargo bikes.
It was consciously decided therefore to examine health risks for cargo bike and vehicle users, within the context of a conversion trajectory, so focussing on the target group (training and testing) candidates as a potential source of data gathering. A specific measurement campaign was then designed to engage volunteers to measure their exposure to black carbon in both modes of transport – their accustomed mobility option (own vehicle) and the cargo bike. Particulates (PM 10 and PM2.5) are the result of incomplete combustion of fossil fuels (black carbon PM2.5 particles have a diameter of less than 2.5 micrometers which represent a real infiltration threat). In urban areas they constitute an effective marker in terms of pollutant levels emitted by road transport, while recent studies show that because of the fineness of the particles they also represent one of the most toxic components of such emissions. The option adopted is therefore to measure exposure to this segment by means of sensors combined with log book recordings, where emission exposure is monitored in relation to the experience and activity pattern of individual users.
The information gathered can then ultimately feed an online tool app at the end of the project, that provides optimal, least polluted, route options for their cargo bike trips. Results directly measured by users ensure a broad data set as well as generating strong ownership of the initiative.
Brussels Environment delivers individual reports to involved participants, using this to help participants interpret the results of their measurements by identifying sources of pollution, factors influencing the presence of pollutants and stimulating reflection on how they can make a concrete contribution to improving air quality. Exposure results will be used to better inform participants and the wider public about air pollution, so using nudging to convince them of the self-interest advantages of using a cargo bike. At the end of the measurement campaign a comprehensive report analysing and interpreting the results will be published – highlighting the differences in exposure to pollutants between modes of transport (cargo bike – combustion engine vehicle). Based on the results obtained recommendations will be made to further optimise and reduce the exposure of cargo bike users.
 This builds on expertise acquired by Brussels Environment through their involvement in the Exp’AIR project since 2013. In contrast to the CurieuzenAir citizen science initiative, the option was firmly taken in Cairgo Bike to examine exposure levels impacting on transport users, at street level, in traffic and specifically focussing on the health risk posed by the black carbon component.