1. Chapter 19: Air Pollution and Noise
Living and Working in a Healthy Environment

2. Sources of the 5 major pollutants in the U
Sources of the 5 major pollutants in the U.S Note: Historically, the 6th Major Pollutant was lead.

3. Source and Composition of Particulates
meteoritic material
soot
sulfates, ash
Soot, sulfates, VOCs
soot
sea salt
Soot, organic
methane,
ammonia
Soot, NOx, VOCs
Minerals, clays

4. Primary standard: Necessary to protect the public health
Texas Air Quality
Let’s consider those compounds that the Federal Government regulates  National Ambient Air Quality Standards (NAAQS)
Secondary standard: Necessary to protect the public welfare and the environment
The Clean Air Act requires these standards to be set at levels that protect public health with an adequate margin of safety and without consideration of cost.
Primary standard: Necessary to protect the public health 4
The light gray standards have been recently added.

5. Lecture 32 Texas Air Quality

6. U.S. Federal Regulation of Air Pollution
Air pollution Control Act of 1955
Clean Air Act of 1963
Amendment to CAA - Motor Vehicle Air pollution Control Act of 1965
1970 Clean Air Amendments and formation of the EPA.
1975 catalytic converter developed.

7. Signs that regulation works!
U.S. pollution
trends since 1977

8. Types of SMOG
1.Industrial London Smog – combination of smoke and fog
At the end of the 1800’s, 40% less sunlight in London than surrounding towns
Health effects
Vitamin D deficiency, Rickets, Tubercolosis

9. 2. Photochemical Smog
Consists mainly of secondary pollutants: Ozone (O3), NO2, VOCs
Forms when sunlight induces chemical changes in gases and aerosols
Causes poor visibility, burning eyes, sore lungs, worsen conditions of the heart and lungs,
possible mortality.

10. Photochemical and Industrial Smog
“London Smog or Industrial Smog”
Gray-air in New York City
“LA Smog”:
Brown-air smog in Los Angeles
© Dean D. Fetterolf/ShutterStock, Inc.
© Chad Littlejohn/ShutterStock, Inc.

11. Ozone (O3) in the Troposphere
Photochemical Smog
Ozone (O3) in the Troposphere
Most problematic air pollutant in many areas of the U.S.
Ozone is not directly emitted into the atmosphere, but instead forms through a complex series of reactions.
It is largely because of this complexity that ozone is so difficult to control.
I usually apologize for the excessive chemistry here, but explain that it’s impossible to discuss tropospheric ozone without it.
Explain that hn simply indicates that a photon is absorbed by the molecule, which leads to decomposition (i.e., photolysis). The n is just frequency.

12. Ozone chemistry (gas-phase only) NO3 N2O5 hn O3 NO2 NO HNO3 HONO HO2
RO2
H2O hn
H2O2
VOC
This represents a simplistic overview of the gas phase reactions involved in ozone production. I highlight NOx and VOCs since these are the precursors that we can control.

13. The next two slides are meant to accompany a discussion of how emissions rates are measured. Measuring what comes out of a stack is pretty straightforward. Measuring the thousands of small leaks in a massive refinery such as those in Houston is more challenging. During TexAQS2000 aircraft measurements indicated that VOC emissions from many of the refineries in Houston far exceeded the reported values.

14. Measuring auto and truck emissions is usually accomplished by either putting the vehicle on a dynamometer and sampling the exhaust, or by sampling pollutant levels in tunnels. The Caldicott tunnel shown above (near San Francisco) has been used extensively for the latter type of study since it has two bores, one of which is used only by cars. This permits separation of the auto emissions from those from diesel trucks.

15. NOx and VOC sources in the Greater Houston Area
The take-home message from these figures is that NOx is emitted almost entirely as a result of combustion, whereas VOC emissions are often dominated by other sources such as trees. The refineries and chemical plants in Houston are important sources of a range of VOCs.

16. Isopleth lines of constant ozone concentration.
This is called an ozone isopleth diagram, and shows the ozone concentration that will result from different NOx / VOC mixtures. The plot on the previous slide essentially represents a vertical line here.
This is called an ozone isopleth diagram, and shows the ozone concentration that will result from different NOx / VOC mixtures. The plot on the previous slide essentially represents a vertical line here.

17. What is a unique hour.(just one hour at a time?)
What is AQMD ??
I think H-G-B is Houston Galveston Beaumont
Explain how sunlight drives photochemistry and causes high OZONE
This shows the number of exceedances in Houston over the past 9 years. Most high ozone days occur in the summer when there is plenty of sunlight to drive the photochemistry, warm temperatures accelerate some of the reactions, and temperature inversions often limit vertical mixing.
After taking the lead in 1999 and 2000, Houston has dropped back below Los Angeles in the number of annual exceedences. The annual variability is caused primarily by meteorology.
This shows the number of exceedances in Houston over the past 9 years. Most high ozone days occur in the summer when there is plenty of sunlight to drive the photochemistry, warm temperatures accelerate some of the reactions, and temperature inversions often limit vertical mixing.
After taking the lead in 1999 and 2000, Houston has dropped back below Los Angeles in the number of annual exceedences. The annual variability is caused primarily by meteorology.

18. 19.2 The Effects of Climate and Topography on Air Pollution
Air pollution levels in a region are affected by a number of factors, among them:
Temperature
Sunlight
Wind
Other climate factors
They are also affected by the topography.

19. FIGURE 05a: Temperature profiles: normal pattern.

20. FIGURE 05b: Temperature profiles: temperature inversion

21. The Health Effects of Air Pollution
FIGURE 6: Urban air pollution and incidence of emphysema in Winnipeg and St. Louis

22. Effects on Plants and Nonhuman Animals
FIGURE 7:
Trees killed by acid deposition in Pisgah Nation Forest, North Carolina
© Jerry Whaley/age fotostock
Air pollution adversely affects plants, animals, and their habitat.
Air pollution damages
many human-made
materials, from metal
to concrete and stone.

23. 19.5 Noise: The Forgotten Pollutant
Sound is characterized by loudness (measured in decibels) and pitch (how high or low it is).

24. How Loud is Too Loud? www.warrencenter.org/howloud.html
Prolonged exposure to any noise above 85 decibels (dB) can cause gradual hearing loss.
At higher decibel levels, hearing protection is strongly recommended.
100 decibels - no more than 15 minutes prolonged exposure recommended
110 decibels - regular exposure of more than one minute risks permanent hearing loss without hearing protection.

25. FIGURE 14: Radon protection
Indoor Air Pollution
Indoor air pollutants come from:
combustion sources
a variety of products that release potentially harmful substances
from naturally occurring radioactive materials in the ground beneath a building
Indoor air pollution is present in millions of homes and offices and adversely affects millions of Americans.
Indoor air pollution has been around for centuries.
Today, problems are created by:
efforts to reduce air infiltration that traps pollutants
the use of many new building materials and products that contain glues and other chemicals that are harmful to human health
FIGURE 14: Radon protection