ENVENG 3200 Final Practice Questions and Answers | Environmental
Engineering Final Exam Review
What are the differences in management of air quality as compared to water quality? - correct
answer ✔✔[Lecture 18, Slide 2]
*1. Air as a resource:*
- air is "free" and "widely available"
- unlike water, it is not treated as resource
*2. Constraints on air movement:*
- air movement is unconstrained and it can cross boundaries as a function of wind, storms, etc.
*3. Treatment of air pollutants:*
- air must be treated at the source, it can not be realistically treated prior to use
Understand air movement at different scales. - correct answer ✔✔*1. GLOBAL:*
*• Sunlight:*
- induces heating that leads to expansion and rising air (lack of sunlight causes the reverse)
*• Rotation:*
- results in air movement, will deflect at the surface
*• Latitude:*
- changes the angle of sunlight and the length of exposure, modify locations of cells
*2. REGIONAL (100s miles):*
• Affected by global air movement
,• Depends on the motion of air parcels with different temperatures and moisture contents
*• Low pressure:*
- characterized by heated surface air rising, CCW air movement, surface wind travels inward,
upward movement
*Local*
- depends on natural or anthropogenic differences in geography
Describe what is air stability and how it affects plume movement from stack during unstable,
stable and neutral conditions? How can air stability affect pollution concentration at specific
distance from source at ground level? - correct answer ✔✔*Air stability:*
- determines dispersion
- low stability leads to high dispersion
- stability is dependent on wind speed
*Stable:*
- vertical movement of an air parcel is discouraged
- air pollutants will not disperse which will cause concentration to increase near the source
*Neutral:*
- vertical movement of an air parcel is not encouraged
*Unstable:*
- vertical movement is encouraged upward/downward air pollutants disperse quickly
- concentration will be lower than is the air was stable
What is inversion? - correct answer ✔✔- When temperature increases with altitude.
, - This happens due to topography, surface cooling at night and interacting weather fronts.
- Happens in large cities and it will trap air
- Prevents pollutants from mixing with clean air above
What are the National Ambient Air Quality Standards (NAAQS) 6 criteria pollutants and how
they affect the human health? - correct answer ✔✔1. *Particulate matter:* lung/heart irritant;
depends on size of particles
2. *Carbon monoxide:* can be adsorbed into bloodstream, affect O2 uptake
3. *Nitrogen dioxide:* lung irritant
4. *Sulfure dioxide:* lung irritant and main source for acid rain
5. *Ozone:* very reactive, strong irritant
6. *Lead:* developmental toxin
What are different sources of air pollution? - correct answer ✔✔*1. Point sources:*
- emitted from a stack
*2. Area sources:*
- not associated with stack, too small to be treated as point source
*3. Mobile sources:*
- highway and off-highway sources
Engineering Final Exam Review
What are the differences in management of air quality as compared to water quality? - correct
answer ✔✔[Lecture 18, Slide 2]
*1. Air as a resource:*
- air is "free" and "widely available"
- unlike water, it is not treated as resource
*2. Constraints on air movement:*
- air movement is unconstrained and it can cross boundaries as a function of wind, storms, etc.
*3. Treatment of air pollutants:*
- air must be treated at the source, it can not be realistically treated prior to use
Understand air movement at different scales. - correct answer ✔✔*1. GLOBAL:*
*• Sunlight:*
- induces heating that leads to expansion and rising air (lack of sunlight causes the reverse)
*• Rotation:*
- results in air movement, will deflect at the surface
*• Latitude:*
- changes the angle of sunlight and the length of exposure, modify locations of cells
*2. REGIONAL (100s miles):*
• Affected by global air movement
,• Depends on the motion of air parcels with different temperatures and moisture contents
*• Low pressure:*
- characterized by heated surface air rising, CCW air movement, surface wind travels inward,
upward movement
*Local*
- depends on natural or anthropogenic differences in geography
Describe what is air stability and how it affects plume movement from stack during unstable,
stable and neutral conditions? How can air stability affect pollution concentration at specific
distance from source at ground level? - correct answer ✔✔*Air stability:*
- determines dispersion
- low stability leads to high dispersion
- stability is dependent on wind speed
*Stable:*
- vertical movement of an air parcel is discouraged
- air pollutants will not disperse which will cause concentration to increase near the source
*Neutral:*
- vertical movement of an air parcel is not encouraged
*Unstable:*
- vertical movement is encouraged upward/downward air pollutants disperse quickly
- concentration will be lower than is the air was stable
What is inversion? - correct answer ✔✔- When temperature increases with altitude.
, - This happens due to topography, surface cooling at night and interacting weather fronts.
- Happens in large cities and it will trap air
- Prevents pollutants from mixing with clean air above
What are the National Ambient Air Quality Standards (NAAQS) 6 criteria pollutants and how
they affect the human health? - correct answer ✔✔1. *Particulate matter:* lung/heart irritant;
depends on size of particles
2. *Carbon monoxide:* can be adsorbed into bloodstream, affect O2 uptake
3. *Nitrogen dioxide:* lung irritant
4. *Sulfure dioxide:* lung irritant and main source for acid rain
5. *Ozone:* very reactive, strong irritant
6. *Lead:* developmental toxin
What are different sources of air pollution? - correct answer ✔✔*1. Point sources:*
- emitted from a stack
*2. Area sources:*
- not associated with stack, too small to be treated as point source
*3. Mobile sources:*
- highway and off-highway sources
