Air quality/air pollution: Refers to the state of the air around us, including the presence of pollutants which may be harmful to human health, the environment, or cause damage to materials.
Air Quality Index (AQI): A standardized numerical scale used to communicate the level of air pollution to the public. The AQI categorizes air quality from "good" to "hazardous" based on pollutant concentrations and their health effects.
Air Quality Management: Strategies and actions undertaken by governments, organizations, and individuals to improve and maintain air quality, including pollution control, emissions reduction, and public awareness campaigns.
Air Quality Management Plan: A comprehensive strategy developed by government authorities to address air quality issues within a specific region or jurisdiction. These plans typically include measures to reduce emissions and protect public health.
Air Quality Standards: Legal or regulatory limits established by government authorities to control and limit the concentration of specific air pollutants to protect human health and the environment.
Carbon Monoxide (CO): A colorless, odorless gas produced during the incomplete combustion of carbonaceous fuels, like gasoline and natural gas. CO can be hazardous to health as it reduces the blood's oxygen-carrying capacity.
Emission Sources: The origins of air pollutants, which can include industrial facilities, transportation (vehicles and aircraft), residential heating, agriculture, and natural sources like wildfires and volcanic eruptions.
Environmental Impacts: Effects of air pollution on the natural world, such as damage to ecosystems, water bodies, soil, and vegetation, as well as contributions to climate change.
Environmental Impact Assessment (EIA): A process that evaluates the environmental impacts of a proposed project or development, including the impact on air quality, to ensure that decisions are environmentally sustainable.
Fine Particulates (PM): Tiny, airborne particles or droplets of solids and liquids suspended in the air. PM is categorized by size, with PM 2.5 (particles smaller than 2.5 microns) and PM10 (particles smaller than 10 microns) being particularly significant for their health and environmental impacts.
Ground-Level Ozone (O3): Ozone found near the Earth's surface, resulting from complex chemical reactions between precursor pollutants in the presence of sunlight. Ground-level ozone can harm respiratory health and is a key component of smog.
Hazardous substances: Chemicals or materials that can pose a significant risk to health or the environment when released into the air, water, or soil.
Hazardous waste: Waste materials that are dangerous or potentially harmful to our health or the environment, often characterized by being corrosive, flammable, reactive, or toxic.
Mortality from PM2.5 Exposure: Estimated premature deaths attributed to PM2.5 exposure per million inhabitants.
Nitrogen Oxides (NOx) Emissions: Nationally-originating human-made emissions of NOx, expressed as NO2, excluding emissions from international transport (aviation and marine).
Noise pollution: Unwanted or disturbing sound that can interfere with normal activities for humans or wildlife, such as hearing, behavior, and sleep disruption.
Ozone layer: A layer in the Earth’s stratosphere containing a high concentration of ozone, which absorbs most of the sun’s ultraviolet radiation. It is crucial for protecting humans and other organisms from UV rays.
Particulate Matter (PM) Size Classes: PM is often categorized into different size classes, including PM1 (particles smaller than 1 micron), PM2.5 (particles smaller than 2.5 microns), and PM10 (particles smaller than 10 microns). These distinctions help assess the depth to which particles can penetrate the respiratory system.
Pollution control: Measures implemented to reduce, control, or eliminate the release of pollutants into the environment, especially those that contaminate the air, water, or soil.
Sulfur Dioxide (SO2): A colorless gas with a pungent odor, primarily produced from the combustion of fossil fuels containing sulfur, such as coal and oil. SO2 is a precursor of acid rain and can harm respiratory health.
Volatile Organic Compounds (VOCs): Organic chemicals that can easily evaporate into the air. VOCs are emitted from various sources, including vehicle exhaust and industrial processes, and contribute to the formation of ground-level ozone and smog.
Welfare Cost of Premature Mortality from PM2.5 Exposure: These costs are presented in millions of constant 2015 USD using PPP, and as a percentage of GDP equivalent. They represent the expenses related to premature deaths attributed to PM2.5 exposure, based on estimates of the "Value of a Statistical Life" (VSL). These estimates exclude impacts other than human health (e.g., effects on structures, agriculture, and ecosystems) and are compared with GDP for illustrative purposes.
