This article examines Puebla’s drastic 1885 Fire Code, which prohibited the use of fossil fuels and other flammables in the city center. Poblano lawmakers embraced Porfirian trends in scientific planning, and their attempts to manage the city according to calculated risks of fire reflected broader concerns with hygiene and the correction of social ills. While engineers and architects defended the law for its ability to prevent chaos, merchants criticized the regulations for hindering commerce. By using the rhetoric of order and progress, opposition groups convinced officials to overturn the law and use municipal funds to establish a professional firefighting brigade. This transition to government-controlled public services was the product of popular mobilization and represented an important step in making Puebla a modern city.