Air Quality Monitoring & Standards Flashcards
6 cards from real CES practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Air Quality Monitoring & Standards flashcards as text
What are the six criteria pollutants regulated under the National Ambient Air Quality Standards (NAAQS)?
Answer: Carbon monoxide, lead, nitrogen dioxide, ozone, particulate matter, and sulfur dioxide
The Clean Air Act requires EPA to set NAAQS for six criteria pollutants: CO, Pb, NO2, O3, PM (PM2.5 and PM10), and SO2. These are widespread pollutants considered harmful to public health and the environment.
What is the difference between primary and secondary NAAQS?
Answer: Primary standards protect public health; secondary standards protect public welfare including crops, vegetation, and buildings
Primary NAAQS are set to protect public health with an adequate margin of safety, including sensitive populations. Secondary NAAQS protect public welfare, including effects on vegetation, animals, buildings, and visibility.
What is PM2.5 and why is it a significant health concern?
Answer: Particulate matter with diameter less than 2.5 micrometers that can penetrate deep into the lungs and enter the bloodstream
PM2.5 (fine particulate matter) particles are small enough to bypass the body's natural defenses, penetrate deep into lung tissue, and even enter the bloodstream, contributing to respiratory and cardiovascular disease.
What is a nonattainment area under the Clean Air Act?
Answer: A geographic area that does not meet one or more NAAQS for a criteria pollutant
EPA designates nonattainment areas when monitoring data shows that ambient air quality fails to meet NAAQS for one or more criteria pollutants. These areas must develop plans to achieve compliance.
What is ground-level ozone and how is it formed?
Answer: A secondary pollutant formed when nitrogen oxides and volatile organic compounds react in sunlight
Ground-level ozone is not emitted directly but forms through photochemical reactions between NOx and VOCs in the presence of sunlight. It is the primary component of smog and a serious respiratory irritant.
What is the Air Quality Index (AQI) used for?
Answer: To communicate daily air quality conditions and associated health risks to the public
The AQI converts measured pollutant concentrations into a standardized scale (0-500) with color-coded categories, helping the public understand current air quality and take appropriate health precautions.