Final answer:
Criteria pollutants are the types of standards that directly limit pollution. Under the Clean Air Act, the EPA has established national air quality standards for six common air pollutants.
Step-by-step explanation:
The types of standards that directly limit pollution are known as criteria pollutants. Criteria pollutants are the types of standards that directly limit pollution. Under the Clean Air Act, the EPA has established national air quality standards for six common air pollutants.
Under the Clean Air Act, the Environmental Protection Agency (EPA) has established national air quality standards for six common air pollutants, which are carbon monoxide, ground-level ozone, nitrogen dioxide, sulfur dioxide, lead, and particulate matter.
These pollutants are called "criteria" air pollutants because they are regulated based on human health-based and environmentally-based criteria.