Final answer:
Emission-control systems aim to reduce environmental pollution by setting limits on emissions and mandating certain technologies, like catalytic converters in vehicles, to clean exhaust gases.
Step-by-step explanation:
The primary purpose of emission-control systems is to reduce pollution from various sources such as automobile tailpipes and industrial smokestacks. This is achieved by setting specific limits on the amount of pollutants that can be emitted into the environment and by requiring the use of specific anti-pollution technologies.
For instance, vehicles are required to have catalytic converters to reduce the emissions of harmful gases such as nitrogen oxides (NOx), carbon monoxide (CO), and volatile organic compounds (VOCs) into the atmosphere, which contribute to air pollution and photochemical smog. Similarly, industrial facilities may be required to use scrubbers or filters to control their emission of pollutants. These measures are part of command-and-control regulation which mandates that companies internalize the social costs of pollution, accounting for them in their production decisions.