Morality in the air : an inquiry into citizen metrologies of air pollution

Air pollution is regarded by a wide range of actors as one of the leading causes of mortality in France. While environmental historians have demonstrated that air pollution has been subject to regulation by public authorities at least since the eighteenth century, the issue gradually took shape throughout the second half of the twentieth century through a process of metrologization — that is, the progressive establishment of measurement as the only legitimate means of apprehending the reality of air pollution. This metrologization lies numerous tensions concerning the quality of measuring instruments, the appropriate ways of measuring air and the possibilities for action afforded by measurement. This dissertation examines how metrologization materializes across different publics (activist, experts, startups) and within differentiated practices, in which air measurement is entangled with experiences, normative horizons, notions of justice, processes of politicization and dispositifs. Focusing on the uses of air pollution microsensors, the dissertation traces how these various actors construct the reality of air pollution through measurement. Our central argument is that the forms of accountability made possible by measurement help explain the divergent interpretations of the reality of air pollution. Indeed, while all these actors agree on the deadly character of these pollutants, thus frequently confront one another in trials of strength, each seeking to assert their own version of the reality of air pollution.