In U.S. pollution regulations, what term is used to describe the air around us?

The term "ambient" is used in U.S. pollution regulations to describe the air around us. This term refers to the surrounding environment, particularly the quality and composition of air in a specific area, without any influence from sources such as industrial emissions or vehicle exhaust. It is critical in assessing air quality because regulations and standards are typically set based on the ambient air quality, which reflects the overall pollution levels that people are exposed to in their daily lives.

Using "ambient" helps in the formulation of policies and regulations aimed at protecting public health and the environment by establishing benchmarks for acceptable air quality levels. It emphasizes the importance of maintaining clean air in communities and guiding efforts to monitor and reduce air pollution. In contrast, terms like "clear," "adjacent," and "idealized" do not accurately reflect the regulatory focus on real-world air conditions and do not carry the same significance in the context of environmental health and safety standards.