Methane is a secondary air pollutant, formed through chemical reactions in the atmosphere involving other pollutants.

Motor vehicles, particularly diesel engines, are the main contributors to NOx emissions due to the high combustion temperatures.

Electrostatic precipitators use an electric field to charge and collect PM particles, effectively removing them from the exhaust gases.

The primary goal of the Paris Agreement is to limit global warming by reducing greenhouse gas emissions, which also contributes to air pollution reduction.

Solar PV systems do not produce any emissions during electricity generation, making them a clean and sustainable alternative for reducing air pollution in urban areas.

Catalytic converters use a catalyst to convert harmful pollutants like NOx into less harmful substances, such as nitrogen and oxygen.

Ozone is a secondary air pollutant formed through chemical reactions involving nitrogen oxides and volatile organic compounds (VOCs) in the presence of sunlight.

Emission control refers to the techniques and technologies used to reduce the release of harmful pollutants from vehicles into the environment.

Biomass energy involves burning organic materials, which can release pollutants into the air, unlike other renewable sources like hydropower, wind, and geothermal.

The Clean Air Act is a comprehensive law aimed at controlling air pollution and improving air quality in the United States.

Carbon dioxide is a greenhouse gas but is not typically considered a major air pollutant emitted by industrial processes.

The photovoltaic effect is the process by which certain materials generate an electrical current when exposed to light, enabling the conversion of sunlight into electricity.

Sulfur dioxide is a major contributor to acid rain, as it reacts with water vapor in the atmosphere to form sulfuric acid.

An air quality index (AQI) provides a standardized measure to communicate the severity of air pollution and its potential health impacts to the public.

While increasing the height of smokestacks can disperse pollutants over a wider area, it does not directly reduce the amount of pollution emitted.