Understanding Air Pollution: CO2, Indoor Pollutants, and Noise Pollution

all right everyone welcome to the last of the three PowerPoints on air pollution

we're gonna hit a lot of learning objectives as we um round out this unit so topic 7.4

atmospheric CO2 in particulates the enduring understanding for this is that human activities have physical chemical

and biological consequences for the atmosphere and you'll see that's a recurring theme through most of these

engineering understandings actually all of them I believe and the learning objective describe natural sources of

CO2 and particulates and to be honest you guys should already know all of that for carbon dioxide anyway

indoor air pollutants we're going to look at a lot of different types of indoor air pollutants but just be able

to identify indoor air pollutants and describe the effects on them primarily for human health we're going to look at

Acid depositions so describe acid deposition and its effects on the environment

and then the reducing air pollution so explain how air pollutants can be reduced at the source

and we will also be talking about noise pollution so describe human activities that result in noise pollution and its

effects both on humans and the environment all right here's the vocab which like usual I will skip

so let's start with carbon dioxide we've talked a lot about carbon dioxide in this class but and and therefore most of

this should be a review recall that carbon dioxide can be emitted from both natural and anthropogenic sources

um so volcanism is a natural source of carbon dioxide whenever you have a volcanic eruption you're going to be

producing some carbon dioxide cellular respiration also natural now that cellular respiration can include two

main Pathways or two types of Pathways that can be aerobic which you should know the formula for and note that

you're producing carbon dioxide and anaerobic now there's many types of anaerobic Pathways some of those produce

methane so methanogenic bacteria are going to be producing methane which is not carbon dioxide but many of these

Pathways can produce carbon dioxide alcoholic fermentation is an example of that so alcoholic fermentation for

bioethanol for example or for beer wine or Spirits is going to produce carbon dioxide two so you take your glucose

with out without oxygen in the absence of oxygen and you break it down using yeast into

ethanol and carbon dioxide and if we were to balance

that we can balance it too so you're producing carbon dioxide whenever anybody's making bioethanol from corn or

from switchgrass you're making carbon dioxide When anybody is making um beer or wine now that is technically

carbon neutral but it's carbon dioxide production nonetheless combustion any type of combustion of

organic molecules is going to produce carbon dioxide okay forest fires indoor cooking fires

Etc and then cement production this one is purely anthropogenic does not occur in

nature but we make carbon dioxide when we heat up this Limestone to produce calcium

oxide or lime which we want for cement production but the carbon dioxide is a waste

product now why does this matter well carbon dioxide is a greenhouse gas

which contributes to global climate change and all of its effects including

including rising sea levels increased temperatures Etc okay more severe storms all of that

all right now let's switch gears and look at indoor air pollutants Now sources of indoor air plugins can be

natural or anthropogenic we'll be talking about all of those in both types um the first one that we're going to

start off with is indoor combustion okay so indoor combustion recall that about a billion people over

a billion people worldwide do not have access to electricity so most of them are cooking their food via fireplace

fires okay we're talking about wood charcoal even propane or kerosene fires okay many of those fires like you see in

this image are indoors because you know it's out of it's out of the weathers depending on the ventilation and the

type of fireplace and all of that you can have more or less particulate matter and other other pollutants in your home

okay but it doesn't have to be a fireplace for cooking it could be a fireplace for heat it could be a wood

burning stove it could be a coal burning stove you could have candles in your house that you're going to be breathing

the particulate matter the soot the smoke from those candles it could be smoking cigarettes for example

all of those are going to be producing some volatile organic compounds as well as carbon dioxide carbon

monoxide which is an asphyxiant recall that it binds to hemoglobin with a greater Affinity than oxygen so if you

have a high concentration carbon monoxide you can asphyxiate right you can

essentially kind of like suffocate and die but it's not suffocation okay

um Ash smoke tobacco smoke particulate matter um

you can have nitrous oxides you can have sulfur dioxide and recall that those will react with the water in your lung

tissue to create nitric acid hno3 or sulfuric acid H2 so

four okay now the concentrations of all those are

going to depend on the conditions in that home right the ventilation how that fireplace is set up what you are burning

Etc when we're talking about these particulate these particulates if we're

just looking at the size of the particulate alone not the not its chemical nature but just the size of the

particulate anything below 2.5 micrometers is what they can what they consider the most concerning the most

damaging to human health this is the size that can get past the the hairs in your nose and the

uh cilia and your trachea and get down into your lungs and start coating the alveoli in your lungs and as it does

that it's very difficult to remove it can lead to coughing fits though it can lead to shortness of breath it can lead

to asthma it can lead to bronchitis emphysema cancer death okay so repeated exposure right cooking your food every

day and breathing in Ash smoke that's 2.5 micrometers or smaller is very concerning for human health

some other sources of indoor air pollutants um include dust so particulate matter we're talking about

that with our particulate matter lab you can have mold like what I'm showing in these pictures down below if you're

breathing in mold spores that can lead to throat irritation nose irritation and can lead to allergic reactions it can

even lead to hemorrhaging that tissue to bleeding of that tissue okay it's really not good to be breathing in mold spores

all the time it can lead to Malaysia sick building syndrome Etc and then we'll talk right on gas on the

next slide so radon gas radon is especially concerning because it is a radioactive gas

because it's radioactive it is mutagenic it's carcinogenic and it's a gas so you breathe it in gets into your lungs and

it is the therefore the second leading cause of lung cancer in the United States right the first is tobacco smoke

among non-smokers it's the leading cause of lung cancer okay so how do you get it in your home well many of our soils many

of our bed much of our Bedrock worldwide contains some radioactive elements and that includes uranium or thorium

uranium or thorium will Decay eventually these do have long half-lives but eventually they will

Decay into radium and then into radon radium isn't that big of a deal because it's a solid right we're going from a

solid solid solid solid to a gas that gas in the soil radon is going to have less density than the

soil than the rock that it's in so it's going to want to rise and that we'll call it a mixture okay it rises up out

of the soil through cracks through fissures through seeps through holes and it gets into the atmosphere

if it's just in the atmosphere not a big deal you're breathing it in a very very low concentrations because it's being

moved around by wind it's going all around the atmosphere and it has a relatively short half-life so it's going

to Decay into polonium pretty quickly relatively quickly

but if it turns to radon below a home then it can get into that home by seeping up through the crawl space

seeping up through cracks in the foundation seeping up into the house itself

once it's inside the house it can concentrate into it can become higher concentrations because it's in an

enclosed space and even though it has a relatively short half-life it can be

um a relatively high concentrations in that home then you're breathing it in and can lead to cancers

the other way that it can enter your water or your home is through the water so if you have ground water you are

probably on or sorry if you're on a well then you're using groundwater and that groundwater can be contaminated with

radon gas that dissolves in that water then it gets into the home via your your well your faucets your sinks Etc

it degases or comes out of solution and then you're breathing it in okay so radon is relatively

um you know troubling worrisome um concerning because again it is

radioactive and is a major source of um of of lung cancers in the United States get radon test kits for your home you

would typically put those in the basement or in the crawl space and you can monitor the levels of radon that you

have if you are concerned about it it's not something that I've ever done at my house because it's I just haven't but

you can install um you can install special types of special fans and strategic locations to

remove that radon or to circulate the air in your home to get lots of fresh air from outside and remove the

potentially radon laced air that's inside now again how it gets in the home from the soil you have uranium you have

thorium you have something in very very small concentrations right not concentrations enough to be alarming you

can still dig in the soil and grow your plants and you know play and you know roll around with the dog in the front

yard it's not that it's gonna it's not anything in the soil that's really going to damage you but that tiny tiny amount

of radioactive material in the Bedrock and the soil can Decay into radium and does Decay into

radon and it can seep up through a crack in your foundation it can seep in through windows and the basement it can

seep in through any types of fittings that you have it can seep in through sump pumps if you don't have a concrete

foundation concrete basement then you might have like a dirt crawl space and it could just seep up through the dirt

into the home and then if again you're on well water which most of you guys are not most of

you are on City water but I'm on well water radon can get into that groundwater and then into from the

groundwater into the well and Trace that water all the way up to your fixtures and once it's

um once it's in you know a space with air it can Degas it can come out of that

water solution and into the air and you can breathe it in now one of the best ways to combat radon

like I've said is ventilation okay you can install um you can install fans in the basement

to to make that air escape the house you know just having the windows open during

the summer is probably enough to reduce the concentration of radon in your home okay

all right let's look at some other types of indoor air pollution now insulation is a pretty major one

if you were doing construction remodeling demolition if you just have um you know your wall your ceilings

covered in sheetrock and or plaster and you're not breathing in if this if this insulation is trapped behind the wall

not a big deal right but once you go to do some remodeling or you go up into the the attic where this insulation is not

covered by sheetrock or plaster then you can start to breathe it in if you're in an old home before they

outlaw asbestos to be used in homes then you can have potentially asbestos insulation okay if you find that you do

and you're remodeling you have to have professionals come in and remove it for you because it is highly carcinogenic

and you have to take special precautions and I'll refer you back to our first excuse me our first PowerPoint and this

unit to talk about asbestos nowadays we use lots of fiberglass or rock wool both of those are particulate

matter can produce particulate matter as well that you can breathe in fiberglass especially is concerning because it is

literally tiny little slivers of glass that look like threads and they really do irritate your nose your mouth your

throat can lead to inflammation severe coughing fits believe me I breathe it in way more fiberglass insulation than I

ever should have and it can include other particulates now we're moving away from fiberglass

insulation as a society and going to more more health conscious types of

insulation that are less impactful but it really depends on the age of your home and what is behind the wall when

you do any remodeling so you should always wear dust masks and respirators or if you have asbestos have

professionals come in now volatile organic compounds these ones are interesting now again a

volatile organic compound is anything that is any organic compound that volatizes or turns from you know a solid

or liquid to a gas solid to a gas sublimation liquid to a gas evaporation at room temperature okay

and there's a lot of petrochemicals that are volatile organic compounds those include chemical solvents they include

adhesives they include um the like shoot um they include preservatives

all kinds of very common chemicals okay so like the solvents that are in your paints lacquers stains varnishes and

waxes like you know this is going to have several types of chemical solvents that Degas over time and once this once

this fast drying polyurethane is dry it's still degassing for weeks to months after after it quote unquote dries okay

many types of cleaning supplies release volatile organic compounds right you smell those organic compounds maybe not

all the compounds that you smell are organic but many of them are organic compounds pesticides you spray raid to

kill the Cockroaches or the ants in your house and you're breathing in volatile organic compounds many of them are

poisonous like I said adhesives glues um you know the weird kids and third

grade that used to sniff glue they're getting high off of these volatile organic compounds and they're also

destroying their brain with these volatile organic compounds uh the smells that you get off of markers like

Sharpies um the inks and printers and copper copiers

and then your fibers okay so like carpet upholstery that

fiber often has volatile organic compounds in it that are used as preservatives one of the biggest ones or

one of the most common and alarming ones is formaldehyde which is used in as a preservative and all kinds of industrial

settings formaldehyde is a carcinogen it is very dangerous it is um it's banned in

schools for example we can't we can't use it as an embalming fluid in schools but it is an embalming fluid and it's um

it's like as an embalming fluid it essentially stops Decay by fixing

biological tissue and by preventing the growth and killing any microorganism that gets onto that tissue so if you put

formaldehyde and very low concentrations on the upholstery for your couch so that microorganisms don't you know

decompose your couch you don't have mold on your couch that would be disgusting you instead put formaldehyde on it the

the the manufacturer does that formaldehyde can Degas over a very long period of time and you can be

breathing it in a very low concentrations for years after buying a couch or after buying your carpet or

after getting the new car smell out of their new car for example okay all of this can lead to what we call sick

building syndrome sick building syndrome is a feeling of Malaysia a feeling of um

tiredness weakness perhaps depression um a feeling of you know perhaps nausea even from being inside for very long

periods of time breathing in all these petrochemicals all these synthetic industrial chemicals

and it's really easy to cure you just go outside for a while right again many of these chemicals

Degas over very long periods of time you may not even smell it for years but you still are breathing in

very small concentrations of these chemicals after you buy your furniture or use your markers or you know stain

your wood floors and then varnish them so here's a diagram overviewing air pollution I'll pause this right now to

where you can see where you would get these different air pollutants in your homes

and let's move on and talk about acid deposition now acid deposition we call it acid deposition because it's the

deposition or depositing of an acid we used to just call it acid rain but that is what we now call wet acid deposition

it's any type of precipitation it could be sleet could be snow

okay does not have to be rain how do we get acid I'm sorry second type

dry dry acid deposition is essentially when you have an acidic gas that just settles out okay we have the ions

created from nitric acid just settling out and you know settling onto the surface of

the soil or onto your waterways it can also collect on Dust particles and settle out that way so say that we have

a dust storm that kicks up a lot of clay and that Clay is really good at attracting hydrogen ions and those that

clay will essentially eventually just settle out and deposit those hydrogen ions onto the surface of the soil or

into your waterways so we call it acid deposition because it does not have to be rain it can also be

dry acid deposition okay now the two main causes of acid

deposition are sulfur dioxide and nitrous oxides okay or nitrogen oxides

sulfur dioxide again is going to make sulfuric acid that will then separate into hydrogen ions

and it can even go a step further and you can have two hydrogen ions and so4 two minus

okay it can also include again nox your noxes right nitrous oxides

if it's nitrogen monoxide that's going to react with oxygen to produce nitrogen dioxide which will then just go down and

react with water to produce nitric acid now it can also just be Nitro nitrogen dioxide

that you start off with as your primary pollutant okay so either of those two primary pollutants

creating these secondary pollutants of acids okay

now remember that normal rainwater is slightly acidic anywhere from pH of five to six okay maybe 5.5 to 6.

now when we I and that's because of the carbonic acid right CO2 reacts in the

atmosphere with water to produce carbonic acid right and that acid will

again dissociate in droplets of water and you'll have your hydrogen ions but this is unusually low

acidic unusually low PH right these acids create unusually low ph and we can also have it from volatile

organic compounds where we most often find it is in your industrial sectors of um of of regions

right so if we're looking at the United States we're talking about the industrial Midwest and Northeast

and because the predominant winds in the United States below from west to east something that's emitted let's say in a

factory from Cleveland or Columbus make it over to New York or Pennsylvania but it's not going to go

over to Nebraska because that's just not the way the predominant winds below you see that also in Europe and Asia so

there's a lot of industry in Central Europe and Eastern Europe specifically and then the dominant winds bring those

into Central Asia and deposit those pollutants in Central Asia lawn away or far away from their source

we have another pocket of high concentrations in um

in uh sorry East Asia as well as in north northwest South America the environmental effects of acid

deposition are wide and somewhat varied but relatively similar but let's go through them step

by step now first off they can easily leech heavy metals from the soil and water so they dissolve these heavy

metals stuff like you know cadmium copper lead even arsenic um

dissolves these heavy metals and transports them somewhere else so let's say that acid deposition acid rain

strikes the rock that has lots of cadmium in it that cadmium can dissolve into that water as it runs off into

soils or nearby bodies of water and cause the deposition of these heavy metals as well as the acid

okay you can also I'll skip down a little bit leech aluminum from the soil and

aluminum is particularly worrying because it is very toxic it's not technically a heavy metal so I have it

on a separate bullet point but basically the same thing happens um

in acidic conditions the this these aluminum ions Leach out of the rock or the soil and they can get transported to

your waterways and it is very toxic we don't think about it as toxic because we use aluminum all the time and the

preparation and storage of our food but it is toxic to many organisms it's just you know stable in the way that we use

it in terms of cooking most of the time now the acidity itself the hydrogen ions themselves can affect water chemistry by

lowering the ph and again this can take out take many organisms out of the range of their tolerances

and it can kill many types of organism it can prevent the shells of any calcareous shell or exoskeleton from

forming or it can even dissolve them in high enough concentrations so it does have very severe impacts for many

aquatic species and the same thing occurring in the soil right lowering the pH it can kill soil

microbes it can Leach nutrients from the soil so taking those nutrients further down into the soil column away from the

roots of the plants it can kill the plants as well so this Forest that I'm showing on the bottom right those trees

are dead because of acid deposition okay it wasn't a forest fire or anything else that killed these trees no insects or

pests it was acid deposition okay now ocean chemistry

many people will think that acid deposition acid rain from sulfuric acid or nitric acid will

cause is what causes um ocean acidification that is not the case

ocean acidification is caused by High atmospheric CO2 levels which leads to CO2 dissolving into the ocean more CO2

dissolving into the ocean which leads to more carbonic acid in the oceans

but you will have some effects if you have an isolated section of ocean near an

industrial center or if you have let's say like a a lagoon that is pretty much cut off from the rest of the

ocean maybe there's only a small little narrow Gap that that's connected to the rest of the ocean with and the tide and

the waves don't really bring in much new water and it doesn't cycle out much of the water from the Lagoon into the ocean

as a whole yes in that case if there's a lot of acid deposition it can affect that isolated system that system that's

isolated from the rest of the ocean but in general the ocean is um turning more acidic you know

decreasing in PH due to carbonic acid and not due to sulfuric or nitric acid okay so please don't let

that confuse you the interesting thing about this is that asset deposition the effects of acid

deposition is going to depend on your local geology if your bedrock and therefore your parent material that

contributes to the soil is limestone then acid deposition will often be neutralized the effects will be

mitigated by that Limestone okay that Limestone will buffer the pH because limestone is a base it's alkaline it

will buffer the pH think back to titrations in chemistry it'll buffer the pH

and it will neutralize that acid okay and because there is so much Limestone bedrock in many of these

places and Limestone soil in these places then it would take a whole awful lot of acid to overwhelm that system to

decrease to to surpass that buffering effect okay so if your bedrock and if your

parent material for your soil is limestone it will mitigate the effects of acid deposition if it's really any

other type of soil or or Bedrock then acid deposition you'll feel the feel you'll feel the full effects

for humans there's little to no negative health effects but if you are breathing in nitrous oxides or sulfur dioxide then

you can be producing those acids in your lungs because they're reacting with water in your lungs and producing the

acid in the lungs itself so if you're breathing in high concentrations you can have

um you know negative human health effects and I'll refer you to the previous

PowerPoint for those but they include asthma bronchitis shortness of breath bleeding of lung tissue scarring of lung

tissue Etc it does acid deposition has a huge cultural effect though any building or

statue that is made out of limestone that has acid rain wash on it all the time is going to become weathered away

so you see a couple examples of that down on the bottom here so it weathers away literally weathers away your

culture in some areas so in order to reduce acid rain we have to reduce the three types of

compounds that contribute to acid rain so the three primary pollutants that lead to acid rain now we haven't talked

about volatile organic compounds much for acid rain or acid deposition but they definitely can lead to acid

deposition there's just too wide of a of a range of a variety of volatile organic compounds

to really talk about them comprehensively so I'm just lumping them as volatile organic compounds and not

giving you the acids themselves that are made but your nitrous oxides and your sulfur dioxide is the main ones okay

some Technical Solutions include catalytic converters on cars and other vehicles and then wet scrubbers sulfur

dioxide scrubbers or flu gas desulfurization and coal burning power plants we'll talk about those both of

those on future slides so I'm going to skip them legislation and Emissions emissions

taxes are always great Solutions as well and again we'll watch this video in class so if you haven't done it already

from the first PowerPoint or even the second in this series watch this if you're not going to be in class only

about three minutes and let's move on to noise pollution this is also called sound pollution or

environmental noise this is any sound that has negative impacts on any organism including humans okay so for

example this Jackhammer that this construction worker is using is creating noise pollution for these people that

are walking right past it or the people in The Office Buildings across the street

the jet this is uh in in London this jet constantly going over the flight path over these houses the constant like

these houses are in the flight path of this airport the constant noise from all of the airplanes traveling over probably

have a um a negative Health effect on these people

that can include elevated stress cardiovascular cardiovascular disorders including hypertension so that that's

going to cause high blood pressure and could cause a heart attack hearing loss and then sleep disruption

all right all of those can be caused by by any type of heavy machinery music explosions except for rock and roll of

course rock and roll ain't no noise pollution like AC DC told us but as a biologist I'm more interested

in the effects that noise pollution has on Wildlife those same effects like elevated stress cardiovascular issues

maybe not as much as animals because of their diet but altered sleep schedules um

occur in animals as well but we have a lot of other effects on Wildlife now for this first part I'm going to go away

from the atmosphere for a little bit we're talking about atmospheric pollution but because we're talking

about noise pollution I'm going to go into the water okay into the Marine systems now there's a lot of different

types of marine organisms that use water or sorry use sound for a lot of different cues okay they might use sound

as their primary means of navigation so you have um you have uh dolphin species you have

fish species that use sound as their primary means of navigation many species communicate with one

another whales and dolphins and porpoises write cetaceans are primary probably your best example of that now

if whales cannot hear each other for mating rituals or whales can't hear uh thin slaps or tail slaps for a mating

courtship rituals or for mating competition if a mother whale can't communicate with

her Offspring using these very low frequencies that we can't even hear with our ears but the whales can hear it the

mother and offspring are constantly in communication the mom always telling The Offspring like hey don't go too far stay

close to me and The Offspring is communicating back with the mother if they can't do that communication because

of all the shipping traffic uh the boat noise from the propellers and from the engines from sonar

um from industry then they might become separated and lost and the child die okay avoiding Predators

hunting also used with noise now in the ocean your main sources of noise are sonar

Transportation so this includes your Motors your engines your propellers any type of Machinery that's on on the

uh on the ship explosions now believe it or not there's quite a few explosions used in the ocean primarily for uh for

drilling or for creating pylons um offshore drilling any type of construction laying down pipes or cables

is going to create noise all of these things will disrupt marine species all right um noise pollution alone has

been implicated in high levels of whales beaching themselves because they're just um become disoriented and I'll give you

like a very short story of when I was recently snorkeling down in um Cabo Mexico I was snorkeling an area that was

sectioned off for swimmers and snorkelers but it was near the main Marina and there was boats constantly

going back and forth and this is right where the humpback whales take their calves

um or go to give birth to their calves so you have all these baby whales around as well and all these mothers trying to

communicate with the baby whales now when I was snorkeling I heard this constant like buzz saw noise

um in the background from all of these boats that were going back and forth all the time and that's something that those

whales now have to deal with that they didn't have to live with a hundred years ago or 200 years ago when I went

snorkeling in a more isolated area it was totally quiet and I can hear the sound of the fish munching on the on the

algae on the rock for example but near the marina um

where all this boat traffic was it was a constant sound of propellers and engines and that's what the these animals have

to deal with and in the atmosphere many terrestrial species also use sound to hunt to

communicate with each other to avoid Predators bats echolocate they use sound for migration so there's a lot of uses

that animals use sound for and there's different effects that noise pollution has on these organisms it can mask their

sound so they're unable to hear one another so a cardinal for example in a very busy City may be seening a mating

song but a female cardinal may not hear it so it's masked because of all the traffic and all of the noise

you can have physiological effects like we talked about before or that I mentioned before you can have behavioral

effects so they could have lower reproduction abandonment mates Etc they can have

different uh different times that they've seen in the City compared to out in the countryside

and the countryside they may seen in the in midday or in the morning but in the city they might start singing at dusk or

Dawn to avoid those daytime hours and that's just a learned behavior that they start to have in the cities but it

changes their behavior so that if you have those two populations the city and the country Birds interacting they may

not be able to pick up on those social cues from one another okay and then these ecological effects

if you have lowered reproduction if you have lower survival all of that it can have trickle-down effects throughout

your food web okay so trophic Cascades all right

and I'd like to watch this uh video in class but if you um are not going to be in class check out this video now

now the last section of this PowerPoint we're going to be talking about ways to mitigate

um pollution okay the first one is atmospheric pollution the first one is the Clean Air Act Now the Clean Air Act

was drafted in 1963 um Amanda in 1965 and then 70 77 and 1990 you don't need to know what

happened at each year what those amendments are I will very briefly give you the Bare Bones summary of what

happened with each one but just have a general idea of what the Clean Air Act is what its goal is and how it can

operate okay this does predate the Environmental Protection Agency the Environmental

Protection Agency or EPA was created in 1970 so this does predate this and as it's written now it defines the

epa's responsibility for improving U.S air quality and stratospheric ozone so we do have to know that this is a U.S

law only okay so it's only for the US

now the original function protect and improve I basically summarize this right off of the EPA

website to protect and improve air quality for the welfare of the US populace promote research in the area of

air pollution control promote and execute state and local Air Pollution Control programs so it works with state

and local um legislation and and policy makers and laws as well and and

um shoot the words um enforcement

now in 1965 there was the national emission standard act so this was a law that basically

said what could and what could not come out of a automobile's tailpipe right out of the exhaust so it sets set standards

and regulations on how automobile manufacturers have to create their vehicles to limit the pollutants

that come out of um out of the back end of these cars and that was primarily to combat smog

and these and and our major cities so one of the big functions of this was to reduce smog in major cities if you look

back at um old photographs from the 60s and 70s of La

um Denver Austin Texas these big cities had way more smog back then than they do now and a lot of that is due to the EPA

and specifically the national emission standards act but also this 1970 Amendment as well the 1970 Amendment

authorized the development of comprehensive federal and state regulations that limit the emissions

from both stationary sources so these are your industrial sources they also include power plants

and mobile sources so that's transportation okay so these mobile sources again

building off of that all right this setup cap and trade

programs for sulfur dioxide from coal burning power plants and it put the Clean Air Act under the jurisdiction of

the APA because the EPA was created in 1970. okay we'll talk about what cap and trade is later on so if you don't know

what that is that's okay we'll talk about it on one of the next slides in 1977 it was

um you know just put stricter enforcement onto all of these uh things I had previously and improved air

quality standards and goals um in 1990 substantially increased Federal Authority and responsibility for

air quality in the United States and broadened to include controls for acid rain and permits for stationary sources

of pollution against stationary sources are industry factories power plants Etc anything that is stationary anything

that's in a fixed location now I should also say that different states and even municipalities within

those states can have stricter laws than the EPA but they cannot have more LAX laws so the federal

um the federal government with the Epi with the Clean Air Act sets these Baseline standards and different cities

such as Denver can have better air quality than the EPA mandates but they cannot have more lacks air quality

standards than the EPA mandates okay and Denver actually has pretty good air quality standards per the EPA like

compared to the Clean Air Act Baseline and compared to many other cities around the United States

okay um the effects of this it's significantly improved air quality in

the United States remember when we were talking about Smog and I showed the top 10 smoggiest cities in the world and no

U.S city even Los Angeles topped that list that's because of the Clean Air Act this basically served as a model for

many other countries for them to create their own legislation and because it improved air quality it

significantly improved human health and the environment so some ways just to sum up some ways to

reduce air pollution we can have Technical Solutions which we'll talk about in the next slides we can have

legislation so that includes the Clean Air Act which again you do need to know

it can include taxing externalities so that could be a pollutions tax for example

energy conservation so something that you and I can do as individuals but corporations can also do as well

alternative fuels so switching from gasoline to maybe E85 bioethanol individual action

Etc okay so maybe not using products that pollute instead of using stains and varnishes

really varnishes that pollute maybe I use natural plant-based oils or maybe I use beeswax to finish my wood my wood

projects okay now going down from this legislation from this Clean Air Act down to this cap

and trade idea cap the EPA like I said set cap and trade for sulfur dioxide for power

plants and um industry in the United States cap what is cap and trade mean cap and trade basically sets a cap or an

upper limit for the amount of emissions that can be released so you cannot go beyond that upper limit

but if you were one of those companies that does pollute more you can get around that by trading a little bit you

can buy some of these credits or allowances some of these sulfur dioxide emissions credits from another company

that pollutes less to where it all evens out to where everybody's basically at their cap

okay some companies can make a profit by doing this by polluting less and then others can sort of get around

the system by polluting more but paying for it okay companies can also Bank their emissions

for later use so it gives companies some flexibility um there's mixed feelings around it but

people have many people think that it does help and does and is a a good viable solution

some Technical Solutions here's two for automobiles so the first is a vapor recovery nozzle this is what you're

probably familiar with filling up your car at the pump but you probably never give it much thought as to why it's

shaped this way uh what's special about it what what's going on inside of this structure inside of that structure is a

really kind of ingenious device that makes it to where any volatizing organic compound any

um you know any hydrocarbon from the gasoline that you're pumping is not going straight into the atmosphere is

not leaking out into the atmosphere instead it's leaking into the nozzle itself and going back down being

funneled back down into the storage tank way down inside of the the underneath of the gas station so it's

called a vapor recovery nozzle it it traps those um those gases those volatile organic

compounds that would otherwise escape and go up into the atmosphere foreign

and prevents them from going into the atmosphere so you probably haven't given

given it much of a thought but you don't smell like an overwhelming smell of gasoline when you're filling up your car

like you would if you're using um just like a you know one of those three one three five red

gasoline things that you might fill up a boat or jet ski or lawn mower with okay catalytic converters these are on all

cars produced after I think the 1980s like early 1980s this is a device might be early 1990s

this is a device that takes the exhaust from your internal combustion engine it's got your

exhaust pipe on it so you know your exhaust goes in there and exits there to the tailpipe

um and it takes many of these primary pollutants that cause acid rain

or cause Smog and it turns them into less less harmful chemicals okay so it takes

carbon monoxide for example and turns into carbon dioxide takes nitrous oxides and converts it into nitrogen gas and

oxygen gas and water takes hydrocarbons and turns them into carbon dioxide oxygen or sorry carbon dioxide and water

okay so even though CO2 is not the most desirable chemical in the atmosphere it's better than carbon monoxide or

volatile organic compounds hydrocarbons it's you know these will lead to photochemical smog and acid rain nitrous

oxides really bad definitely better to have nitrogen gas in the atmosphere so your catalytic converter turns these

more harmful gases into less harmful gases and in many cases totally neutral benign gases

and finally what we can put on stationary sources now these stationary sources

can be like I've said industry so that could be coal being burned at a steel foundry or a glass Foundry

it could be a power plant primarily oil including diesel

and coal it could be used and I guess industry and power plants are really the two big

ones um you have scrubbers so wet and dry scrubbers

those are devices that remove particulates or gases depending on what they're chemically designed to remove

from your exhaust gas from your flue gas okay so flue gas is the exhaust gas coming out of the flu out of the uh

chimney for lack of a better term of these power plants or foundries okay an example is flu gas

desulfurization before we get into that let's talk about the difference between wet and dry dry

scrubbers just use a dry medium like a dust to have pollutants bind to okay so

they'll spray in a dust or they'll have a dust circulating inside of this this tank for pollutants

to become attracted to to bind with and then it all settles down to the bottom a wet scrubber uses liquids to remove

those pollutants and the example that I have again is a SO2 scrubber or a flu gas desulfurization

that essentially has your flue gas go in and you have um

sulfur dioxide and your flue gas that sulfur dioxide reacts with aqueous limestone

so that limestone is down here circulates up via that pump and gets sprayed down at the top

um Limestone again is calcium carbonate CO3 um

the sulfur dioxide will react with the calcium carbonate and produce calcium this is getting really messed up

calcium sulfate that calcium sulfate is also known as gypsum and if it as it settles down to

the bottom right that solid gypsum settles down to the bottom if it's pure enough it can be sold to Industry so

that's a really cool way to use your waste gas to create a product that you can then sell for

um for industrial applications gypsum for example is used to make to make sheetrock

so like the walls around us are made of sheetrock or at least uh covered in sheetrock okay

so that's one example of a wet scrubber you can have wet scrubbers that remove particulates you can have wet scrubbers

that remove nitrous oxides it really just depends um you can have wet scrubbers that remove volatile organic

compounds it really just depends on what you're trying to mitigate but the most common is probably your SO2 scrubber or

your flue gas desulfurization bag filters this is just like the filter that you probably have seen on the

engine of your car it's essentially a fabric device that removes particulates so you send your flue gas through a bag

filter and it removes a lot of the particulates um from that uh from that gas right as

the as the as the flue gas as your exhaust gas goes through this filtering device this paper

filter or fabric filter it's just going to remove a lot of the a lot of the solid particles

an electrostatic precipitator is pretty cool this is a more high-tech fancy device that also removes particles

essentially what you have is a series of electrodes inside of your let's just say that we have particulate

matter going through here and we have a series of electrodes going all the way up this exhaust pipe

that series of electrodes has a uh has a negative charge which is going to attract all kinds of particulates

that tend to be positively charged okay once they are positively or once they're attracted to it they can

periodically be cleaned it's kind of like those electric air filters that you might have at home you send an electric

current through a series of metal electrodes and that negative charge will attract dust and any type of particulate

the particulates will stick to the electrode and you can periodically clean them

all right this PowerPoint is getting pretty long but let's just quickly go through the Essential Knowledge CO2

naturally appears in the atmosphere from respiration decomposition volcanic eruptions and then there's a variety of

natural sources for particulates matters as for a particulate matter as well we talked about many of those on our first

PowerPoint in this series so I really didn't hit it here except for combustion the indoor air pollutants was pretty big

on this one this first part with carbon monoxide acting as a suffix again we mostly covered in that first lecture as

well indoor air pollutants are classified as particulates include asbestos dust and

smoke you can also include mold spores in there as well indoor air pollutants you can also

include like fiberglass insulation really anything that's a particulate indoor air pollutants can come from

natural sources man-made sources and combustion common natural sources of indoor air pollutants include radon mold

and dust we spent more time on radon but mold and dust as well uh common human-made indoor air pollutants include

insulation volatile organic compounds from furniture paneling carpets formaldehyde from building materials

Furniture Upholstery and Carpeting and lead from paints we really hit this one in that first PowerPoint too and that

formaldehyde again acted as a preservative on all of these um on all of these things

so that they don't rot but they're but it Degas is very slowly over time and you're still breathing it in

um common combustion air pollutants include carbon monoxide nitrous oxides nitrogen oxide sulfur dioxide

particulates tobacco smoke we talk quite a bit about radon and then radon how radon gas gets into

homes and what it can lead to specifically cancers well more specifically lung cancer

all right we talked about acid deposition I'm going to skip over to this one on the right acid deposition is

due to nitrogen oxides and sulfur oxides in the atmosphere which react and create nitric acid and sulfur sulfuric acid the

Nitric oxides come from motor vehicles and coal burning power plants while the sulfur dioxides come from coal burning

power plants or anywhere else that coal is burned including steel foundries iron foundries glass foundries

Etc okay asset deposition mainly affects communities that are downwind from coal

burning power plants the acid rain and deposition can lead to the acidification of soils and bodies of water and

corrosion of human-made structures I would call that weathering of human-made structures right your Limestone statues

and building facades and all that Regional differences in soils and Bedrock affect affect the impact that

Limestone or sorry that acid deposition has on the region Limestone Bedrock has an ability to buffer or neutralize the

effect of acid rain on lakes and ponds and even in your soil if we look at reduction of air

pollutants we can include regulatory practices so laws and regulations we can include conservation practices okay so

using less electricity using less fuel in your vehicles or using alternative fuels or alternative energy

sources renewable energy sources specifically we talked about vapor recovery nozzles

we talked a little bit about catalytic converters we talked about wet and dry scrubbers and

some methods at power plants such as scrubbers Electro press electrostatic precipitators and bag filters

and finally we talked about noise pollution but I'm going to more or less skip that because this is getting way

too long and I hope that you guys have a great day and I'll see you in class bye