What are fugitive emissions?

Fugitive emissions refer to pollutants that escape from processes or activities without passing through a direct, controlled pathway such as a smokestack or ventilation system. This means that these emissions can come from a variety of sources, including leaks from pipelines, valves, tanks, and any other equipment where gases or volatile substances can unintentionally escape into the atmosphere.

This concept is particularly important in understanding air quality because fugitive emissions can contribute significantly to overall pollution levels, yet they are often more challenging to measure and regulate compared to emissions that have specific, controllable outlets. The other options listed do not correctly encapsulate this definition, focusing instead on aspects that do not accurately characterize what fugitive emissions are. For instance, human-made pollutants that are easily identifiable by their source typically fall under more conventional emissions rather than fugitive emissions.