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AIR POLLUTION SOURCES
AIR POLLUTION SOURCES
Air is one of the essential factors making life on the Earth possible.
Protection of air from pollution is a matter of great importance.
Oxygen un nitrogen compose 99 % of inhaled air.
Unfortunately, we inhale also:
Droplets of the
Very small amount of
2Pollutants spread rapidly and to far
distances in the atmosphere
Troposphere contain almost 95 %
of the all air mass
3A AIIR R P PO OL LL LU UT TIIO ON N S SO OU UR RC CE ES S
Both industrial processes and heating contributes to air pollution.
Air pollution comes from:
FiresSecondary pollutants (sulphur acid) are deriving in air
from primary pollutants in chemical reaction between
Primary pollutants (sulphur
primary pollutant air compounds
dioxide) come in air directly by
natural or anthropogenic
N NO O S SO O H HN NO O
2 2 3 3 3 3
S Su us sp pe en nd de ed d
H SO H O
participles 2 4 2 2
6Schematic drawing, causes and effects of air pollution: (1) greenhouse effect, (2)
particulate contamination, (3) increased UV radiation, (4) acid rain, (5) increased ground
level ozone concentration, (6) increased levels of nitrogen oxides.A A Aiiir r r p p po o ollllllu u ut t tiiio o on n n
Pollutants spread rapidly and to far distances in the atmosphere; therefore, the
problem of atmospheric pollution should be dealt with on a global scale, and
international cooperation is vital in this regard.
Turbulence made by airplanes
A Ai ir r m mo ov ve em me en nt t a an nd d t tu ur rb bu ul le en nc ce e t to o
make easy dissipation of the
Nowadays countless very harmful substances can enter the air of a work area or the
atmosphere in the form of gas, vapour, aerosols or dust. Some of them return back on
the Earth surface in a form of solid participles, drops of liquid or polluted rain.
8H H HIIIS S ST T TO O OR R RY Y Y O O OF F F A A AIIIR R R P P PO O OL L LL L LU U UT T TIIIO O ON N N
The air pollution problem has been accompanying us already since the times the
ancient people discovered fire.
The ancient people’s health or even life were endangered by high concentrations
of such pollutants as carbon monoxide (CO) released from incompletely burnt
firewood and other compounds emitted during burning.
Furthermore, the ancient Romans already knew about lead and mercury poisoning
A Al lr re ea ad dy y i in n 1 12 27 73 3. . E Ed dw wa ar rd d I I, , t th he e k ki in ng g o of f E En ng gl la an nd d f fo or rb bi id d t to o b bu ur rn n l lo ow w q qu ua al li it ty y c co oa al l, , t to o
reduce air pollution.
Air pollution hazard has sharply increased since
the development of Industrial Revolution and the
smoke tails from factory chimneys
new hazardous substances
(petrol with tetra-ethyl lead)
9A A Aiiir r r p p po o ollllllu u ut t ta a an n nt t ts s s
In troposphere are thousands of air pollutants, but main air pollution
comes from substances of the nine groups :
1. Carbon oxides (CO un CO )
2. Sulphur oxides (SO un SO )
3 3. . Ni Nit tr ro og ge en n o ox xiid de es s ( (N N O O, , N NO O u un n N NO O ) )
2 2 2 2
4. Volatile organic substances
methane (CH ), benzol (C H ), formaldehyde
4 6 6
(CH O), freon‘s
5. Dispersed solid participles
dust, soot, pollen, asbestos, compounds of lead, arsenic,
cadmium and other heavy metals, nitrates, sulphates,
drops of liquid with sulphur acid, oil products, dioxins',
polycyclic biphenyl's, pesticides
10A A Aiiir r r p p po o ollllllu u ut t ta a an n nt t ts s s
6. Photo-chemical oxidant’s - ozone (O ), peroxsil-nitrates,
hydrogen peroxide (H O ), hydroxyl radical (OH ), aldehydes, which forms
in atmosphere under reaction between oxygen, nitrogen oxides and
volatile hydrocarbons in presence of Sun radiation
7. Radioactive substances (radon (Rn ),
131 90 239
iodide (J ), strontium (Sr ), plutonium (Pu )
a an nd d o ot th he er r r ra ad di io oa ac ct ti iv ve e i is so ot to op pe es s, , w wh hi ic ch h c co om me es s i in n
atmosphere in gaseous or dispersed form
8. Heat always to result, when one energy form converting into
other, especially by burning fossil fuel in car’s engine, furnace of
factory, thermo-electro plant, stove or fireplace
9. Noise , rises using transport vehicles,
mechanisms in industry or building, devices for households
(vacuum cleaner, radio, mower, etc).
11A A Aiiir r r p p po o ollllllu u ut t tiiio o on n n t t tr r re e en n nd d ds s s iiin n n t t th h he e e w w wo o or r rllld d d
Considerable pollution source group is motor
transport – as motor exhaust gases contain various
The exhaust gas composition may differ depending
on driving habits, engine operating conditions, fuel
supply and quality.
In the process of incomplete combustion of fuel
hydrocarbons, they are transformed into
carcinogenic substances – polyaromatic
Although a range of air environmental protection measures are being implemented today, it is
estimated that the losses incurred by the effects of polluted air on the human health – medical
expenses, loss of working capacity – still amount to hundreds of millions of EUR’s per year just
in the European Union
War is one of the substantial air polluter
To protect both workers and residents, several criteria (limit value) have been
established in order to limit the maximum permissible concentrations of various
harmful substances in the air.
12P Po ollllu ut tiio on n f fr ro om m W Wa ar r
Agent Orange, rocket fuel, lead, mercury, petroleum, asbestos, countless carcinogenic solvents.
This toxic stew settles into the soil in which we grow our food, seeps down into the water we
drink and floats unseen in the air we breathe making us sick — terribly sick – and killing many
of us, or leading to birth defects, cancer, miscarriages, and kidney and thyroid disease.
More recently in Alaska, as a result of nuclear testing off that state’s coast, doctors say workers there will
develop cancer at twice the rate as the general public.
The Vietnamese Red Cross estimates that 150,000 children have birth defects caused by the U.S. military’s
spraying of Agent Orange during the Vietnam war.
13Smog is a type of air pollution; the word "smog" is a combination of
“smoke” and “fog”. Modern smog is a type of air pollution derived
from emission from internal combustion engines and industrial fumes
that react in the atmosphere with sunlight to form secondary
pollutants that also combine with the primary emissions to form
Smog is also caused by large amounts of coal burning in an area caused by
a mixture of smoke, sulphur dioxide and other components.
The term "smog" is generally attributed to Dr. Henry des Voeux in his 1905 paper, "Fog and Smoke"
for a meeting of the Public Health Congress.
Characteristic coloration for smog in California in the beige cloud bank behind Golden Gate Bridge. The brown
coloration is due to the NO in the photochemical smog.
xP PH HO OT TO OC CH HE EM MI IC CA AL L S SM MO OG G
Photochemical smog was first described in the
1950s. It is the result of chemical reaction
of sunlight, nitrogen oxides and volatile
organic compounds in the atmosphere.
This mixture of air pollutants can include the
aldehydes; nitrogen oxides, especially,
nitrogen dioxide; peroxyacil nitrates;
tropospheric ozone; volatile organic
c co om mp po ou un nd ds s. .
All of these chemicals are usually highly
reactive and oxidizing. Photochemical
smog is therefore considered to be a
problem of modern industrialization.
It is present in all modern cities, but it is more
common in cities with sunny, warm, dry
climates and a large number of motor
Because it travels with the wind, it can affect
sparsely populated areas as well.
Heavy smog in Moscow. Russia.
Domodedovo International Airport. 2010. H HE EA AL LT TH H E EF FF FE EC CT TS S B BY Y S SM MO OG G
Smog is a serious problem in many cities and continues
to harm human health.
Ground level ozone, nitrogen dioxide, sulphur dioxide
and carbon monoxide are especially harmful for
senior citizens, children, and people with heart and
lung conditions such as emphysema, bronchitis and
It can inflame breathing passages, decrease the lungs'
working capacity, cause shortness of breath, pain
when inhaling deeply, wheezing, and coughing. It
can cause eye and nose irritation and it dries out the
protective membranes of the nose and throat and
i in nt te er rf fe er re es s w wi it th h t th he e b bo od dy y''s s a ab bi il li it ty y t to o f fi ig gh ht t i in nf fe ec ct ti io on n, ,
increasing susceptibility to illness.
Hospital admissions and respiratory deaths often
increase during periods when ozone levels are high.
The USA EPA has developed an Air Quality Index to help
explain air pollution levels to the general public:
- eight hour average ozone mole fractions of 85 to 104
nmol/mol are described as "Unhealthy for Sensitive
Groups", 105 nmol/mol 124 nmol/mol as
"unhealthy" and 125 nmol/mol to 404 nmol/mol as
Highland Park Optimist Club wearing
- the "very unhealthy" range for some other pollutants
smog-gas masks at banquet,
are: 355 μg m−3 - 424 μg m−3 for PM ; 15.5
Los Angeles, 1954.
μmol/mol - 30.4 μmol/mol for CO and 0.65
μmol/mol - 1.24 μmol/mol for NO
.M MA AJ JO OR R S SM MO OG G I IN NC CI ID DE EN NT TS S I IN N T TH HE E U US SA A
1948, October, 30-31, Donora,
PA: 20 died, 600
more stricken. Lawsuits
were not settled until
1953, November, New York:
Smog kills between 170
and 260 people,
1954, October, Los Angeles:
heavy smog shuts down
schools and industry for
most of the month,
1963, New York: blamed for
1966, New York: blamed for
Smog in New York City as viewed from the World
Trade Center in 1988
17P Ph ho ot to oc ch he em mi ic ca al l s sm mo og g
18P PH HO OT TO OC CH HE EM MIIC CA AL L S SM MO OG G – – A AR RE EA AS S A AF FF FE EC CT TE ED D
Photochemical smog more frequently happening in places, where is sunny, hot and dry
climate, as well as, heavy street traffic.
Beijing air on a day after rain (left)
and a smoggy day (right), August 2005.
Characteristic smog cities are Los Angeles, Denver,
Sidney, Mexico City, Toronto, Beijing, Manila, Ruhr
Areas, Buenos Aires, however smog usually are in
19IIN ND DU US ST TR RIIA AL L S SM MO OG G
Burning coal and heavy oil fractions with high content of sulphur compounds, a industrial smog take shape.
Earlier its happened mainly in winter time.
Industrial smog consist manly of sulphur dioxide, droplets of sulphur acid and solid
Claude Monet made several trips to London between
1899 and 1901, during which he painted views of the
Thames and Houses of Parliament which show the sun
struggling to shine through London's smog-laden
20D DIIS ST TR RIIB BU UT TIIO ON N O OF F T TH HE E P PO OL LL LU UT TIIO ON N IIN N A AIIR R
Normal distribution of
pollution in air
Warm inversion layer
Thermal inversion and
concentration of pollution in
21Fog in Riga
22S So olliid d p pa ar rt tiic ciip plle es s b by y s siize ze
Small participles Big participles
Sea salt dust
Pigments of paint
P Po ol ll le en n
T To ob ba ac cc co o s sm mo ok ke e
Dust from metallurgy
Pollen by magnification
0,001 0,01 0,1 1,0 10,0 100,0
Micrometers (μm) or microns
23D Diis st tr riib bu ut tiio on n o of f t th he e p po ollllu ut tiio on n iin n c ciit tiie es s
Air pollution in urban territories are distributed not only by non-equal heating of
the Earth surface by Sun, but by specific of the city planning and building – as
result there take a shape “heat islands” too.
Effect of the trees on air flows in cities
Turbulence of the air flow in city’s streets with high,
but regular structure
24A AC CIID DIIC C P PR RE EC CIIP PIIT TA AT TIIO ON N
Burning coal or heavy oil fractions in air is emitted huge quantity of the
sulphur dioxide (SO ), solid participles and nitric oxides.
For reduction of local pollution in
Local pollution has been
50-60-ies of the 20 century has been built
reduced, but in territories
more and more higher chimneys, which
before the wind pollution
distribute pollution above thermal
g gr ro ow wt th h r ra ap pi id dl ly y a an nd d p po ol ll lu ut te ed d
i in nv ve er rs si io on n l la ay ye er r. .
Since 1950 global pollution with sulphur and
nitrogen oxides increased threefold.
25N NA AT TU UR RA AL L P PH HE EN NO OM ME EN NA A A AN ND D A AI IR R P PO OL LL LU UT TI IO ON N
The principal natural phenomena that contribute acid-producing gases to the
atmosphere are emissions from volcanoes.
Thus, for example, fumaroles from Laguna Caliente crater of Poas Volcano create
extremely high amounts of acid rain and fog with acidity 2 of pH, clearing an
area of any vegetation and frequently causing irritation to the eyes and lungs of
inhabitants in nearby settlements.
A Ac ci id d- -p pr ro od du uc ci in ng g g ga as ss se es s a ar re e c cr re ea at te ed d a al ls so o b by y b bi io ol lo og gi ic ca al l p pr ro oc ce es ss se es s t th ha at t o oc cc cu ur r o on n t th he e
land, in wetlands, and in the oceans. The major biological source of sulphur
containing compounds is dimethylsuphide.
Nitric acid in rainwater is an important source of fixed nitrogen for plant life, and is
also produced by electrical activity in the atmosphere such as lightning.
Acidic deposits have been detected in glacial ice thousands of years old in remote
parts of the globe.
Soils of coniferous forests are naturally very acidic due to the shedding of needles
and this phenomenon should not be confused with acid rain.
26H HU UM MA AN N A AC CT TIIV VIIT TY Y A AN ND D A AIIR R P PO OL LL LU UT TIIO ON N
The principal cause of acid rain is sulphur and nitrogen
compounds from human sources, such as electricity
generation, factories, and motor vehicles.
Coal power plants are one of the most polluting. The gases
ca can n b be e ca car rr riie ed d h hu un nd dr re ed ds s o off ki killo om me ette er rs s iin n tth he e a attm mo osp sph he er re e
before they are converted to acids and deposited.
In the past, factories had short funnels to let out smoke but this
caused many problems locally; thus, factories now have taller
However, dispersal from these taller stacks causes pollutants
to be carried farther, causing widespread ecological damage.
27Coal-fueled power generating station in Ekibastuz, The Inco Superstack in Sudbury, Ontario, with a height
Kazakhstan. Built in 1987, has installed capacity of of 380 metres, is the tallest chimney in Canada and the
1,000 MW and has the world's tallest flue gas stack Western hemisphere, and the second tallest
at 419.7 metres freestanding chimney in the world
28C CH HE EM MI IC CA AL L P PR RO OC CE ES SS SE ES S
In the gas phase sulphur dioxide is oxidized by reaction with the hydroxyl radical via
an intermolecular reaction:
SO + OH → HOSO
which is followed by:
HOSO + O → HO + SO
2 2 2 3
In the presence of water, sulphur trioxide (SO ) is converted rapidly to sulphuric acid :
SO (g) + H O (l) → H SO (l)
3 2 2 4
N Ni it tr ro og ge en n d di io ox xi id de e r re ea ac ct ts s w wi it th h O OH H t to o f fo or rm m n ni it tr ri ic c a ac ci id d: :
NO + OH → HNO
When clouds are present, the loss rate of SO is faster than can be explained by gas
phase chemistry alone. This is due to reactions in the liquid water droplets.
Hydrolysis: sulphur dioxide dissolves in water and then, like carbon dioxide, hydrolyses
in a series of equilibrium reactions:
SO (g) + H O ↔ SO ·H O
2 2 2 2
SO ·H O ↔ H + HSO
2 2 3
− + 2−
HSO ↔ H + SO
3 3F Fo or rm ma at tiio on n o of f t th he e a ac ciid diic c p pr re ec ciip piit ta at tiio on n
sulphur acid (H SO )
and nitric acid (HNO )
Soil dust and ammonia partly
neutralize acidic salts
Acidic droplets mixes with
rain or snow producing acid
(SO ) and nitrogen
F Fo or rm ma at ti io on n o of f s sa al lt ts s, ,
d di io ox xi id de e ( (N NO O ) )
but sulphates and
nitrates fall down
In lakes, especially in
Farm more shallow, water
become more acidic
Water drops and solid participles fall down un surface quite soon, therefore “acid rains” are
more regional, instead of continental or global problem.
30Processes involved in acid deposition (note that only SO and
NO play a significant role in acid rain).
xH HO OW W A AC CIID DIIC C A AR RE E E EN NV VIIR RO ON NM ME EN NT T ? ?
In chemistry, pH is a measure of the
acidity or basicity of an aqueous solution.
gastric juice (1,0-3,0),
Acid fog (2,0-
lemon juice (2,3)
eel, trout (4,5)
coffee, bred, pike
Industrial areas and big cities
u ur ri in ne e ( (5 5, ,0 0- -7 7, ,0 0) )
w wa at te er r ( (5 5, ,0 0- -5 5, ,6 6) )
c ch ha ar ra ac ct te er ri iz ze e r ra ai in n a ac ci id di it ty y a as s p pH H≈ ≈4 4
milk (6,6), saliva, salmon,
At very polluted places acidity can be
blood (7,3-7,5), eggs
tenfold higher with pH≈3
Sea water (7,8-
baking natron, phosphate
In some places, situated before the
detergents, chlorine bleach
wind from big cities and active industrial
territories, as well as on mountain
ammonia solution (10,5-
ranges and summits pH=2,3
Alkaline cleaning fluid
32H HO OW W A AC CIID DIIC C A AR RE E E EN NV VIIR RO ON NM ME EN NT T ? ?
Hydrangea Hydrangea macrophylla blossoms vary from pink to
blue, according to a pH-dependent mobilization and uptake of soil
aluminium into the plants.
33This chart shows that not all fish, shellfish, or the insects that they eat can tolerate the same
amount of acid; for example, frogs can tolerate water that is more acidic (i.e., has a lower pH)
than trout.H HO OW W A AC CIID DIIC C A AR RE E H HU UM MA AN N ? ?
The pH of different cellular
compartments, body fluids, and organs
is usually tightly regulated in a process
called acid-base homeostasis.
The pH of blood is usually slightly basic
with a value of pH 7.365. This value is
often referred to as physiological pH in
biology and medicine.
Plaque (iekaisums) can create a local
a ac ciid diic c e en nv viir ro on nm me en ntt tth ha att c ca an n r re es su ulltt iin n
tooth decay (sairšana) by
Enzymes and other proteins have an
optimum pH range and can become
inactivated or denatured outside this
The most common disorder in acid-base
homeostasis is acidosis, which means
an acid overload in the body, generally
defined by pH falling below 7.35.
35E EM MP PH HY YS SE EM MA A
Emphysema is a long-term, progressive disease of the lungs that primarily causes
shortness of breath. In people with emphysema, the tissues necessary to support
the physical shape and function of the lungs are destroyed.
It is included in a group of diseases called chronic obstructive pulmonary disease or
COPD (pulmonary refers to the lungs).
Emphysema is called an obstructive lung disease because the destruction of lung tissue
around smaller sacs, called alveoli, makes these air sacs unable to hold their
functional shape upon exhalation.
It is often caused by long-term exposure to air pollution or smoking.C Co on ns se eq qu ue en nc ce es s o of f t th he e “ “a ac ciid d r ra aiin ns s” ”
“ “A Ac ci id d r ra ai in ns s” ” induce chain of the undesirable effects on
land, if pH5,1.
Damage of monuments, buildings,
Wash out of soil Ca
a an nd d K K c co om mp po ou un nd ds s, , w wh hi ic ch h
a nutrients for
Wither away trees, especially, coniferous trees, which grow on
mountain slopes, exposed to acid fog and acid clouds flows
Small solid participles, mainly sulphates, form a mist in
many industrial countries and regions
37Since 1998, Harvard University wraps some of
the bronze and marble statues on its campus,
such as this “Chinese Stele", with waterproof
covers every winter, in order to protect them
from erosion caused by acid rain
Trees killed by acid rain.
(or, actually, acid snow).
38C Co on ns se eq qu ue en nc ce es s o of f t th he e “ “a ac ciid d r ra aiin ns s” ”
“ “A Ac ciid d r ra aiin ns s” ” induce the undesirable effects in
water ecosystems, if pH5,5
Under acidification processes in the lakes non-toxic inorganic mercury substances
transform into very toxic methyl-mercury, which dissolve in fats and can
accumulate in fishes, therefore to cause real threats for people, who consume
these poisoned creations.
Fishes, water plants and
microorganisms perish in the lakes
If pH to decline under 6, many fish species lose their ability for reproduction, but, if in water
pH4,3, fish don’t live at all.
39E EX XT TE EN NS SIIO ON N O OF F R RE EG GIIO ON NS S W WIIT TH H “A “AC CIID DIIC C P PR RE EC CIIP PIIT TA AT TIIO ON N” ”
Sensitive soils, Air pollution regions, Very
potentially emissions arouse the problematic
problematic regions “acid rains” regions
40“F “Fo or re es st ts s’’ d de ea at th h” ” a ar re ea as s iin n E Eu ur ro op pe e
Damage of forests, %
“Acid rains”, which originate in
one country, can be transfer to
other countries by wind.
Intensity levels of
Norway, Switzerland, Austria,
Sweden, Netherland and
Finland receive ¾ of “acid
rains” from other countries.
41A AIIR R P PO OL LL LU UT TIIO ON N IIM MP PA AC CT T O ON N F FO OR RE ES ST T
Direct impact on
leaves or needles
( (k ka ai it tē ēkļ kļi i) )
S St tr re en ng gt th he en n
Damage of bark
and Crown of
the tree and
Release of toxic metal ions
Washing out Difficulties to
of acids and
42A AIIR R M MO ON NIIT TO OR RIIN NG G IIN N L LA AT TV VIIA A
Air monitoring in Latvia is carried out by Environment, geology and
meteorology centre by using differential optical absorption
spectrophotometric stations and devices.
Regular air monitoring measure
c co on nc ce en nt tr ra at ti io on n o of f s su ul lp ph hu ur r d di io ox xi id de e ( (S SO O ) ), ,
nitric dioxide (NO ), ozone (O ), benzol
(C H ), solid participles PM and PM
6 6 10 2.5
Device for measurements of
solid participles PM and
43A AIIR R M MO ON NIIT TO OR RIIN NG G S ST TA AT TIIO ON NS S IIN N R RIIG GA A A AN ND D L LA AT TV VIIA A
air monitoring stations for traffic pollution
air monitoring stations for background
air monitoring stations for industrial
44A AIIR R M MO ON NIIT TO OR RIIN NG G S ST TA AT TIIO ON NS S IIN N L LA AT TV VIIA A,, 2 20 01 10 0
National monitoring programme, 2010.
Air quality stations in cities
Regional reference stations
Opsis AB is a global company that develops,
manufactures and markets state-of-the-art, innovative
systems for gas analysis and process control. Our goal
is to provide our customers with the most advanced,
reliable and cost-effective systems, regardless of
applications. Systems are available for ambient air
quality monitoring (AQM), continuous emissions
monitoring (CEM) and process control. Several
hundred systems are installed worldwide. By focusing
on our customers’ requirements and on continuous
research and development, Opsis continues to lead the
way and set the standard in gas monitoring.
A NEW CONCEPT
Opsis was founded in 1985 when two Ph.D. students
from the University of Lund, Sweden, took the concept
of measuring gases with light and developed it into a
commercially viable product. Svante Wallin and Leif
Unéus developed the idea of measuring gases in air,
by using light, to measure several gases
Opsis is certified according to ISO 9001 quality system
and ISO 14001 environmental quality system.
46Air Quality Modelling Software
Data Acquisition, Validation
The basis of the principle used by Opsis to identify and measure concentrations of different gases is scientifically well established: Differential Optical
Absorption Spectroscopy (DOAS), which is based on Beer-Lambert’s absorption law. It states the relationship between the quantity of light absorbed
and the number of molecules in the light path.
Because every type of molecule, every gas, has its own unique absorption spectrum properties, or “fingerprint”, it is possible to identify and determine
the concentrations of several different gases in the light path at the same time.
DOAS is based on transferring a beam of light from a special source – a high-pressure xenon lamp – over a chosen path and then using advanced
computer calculations to evaluate and analyse the light losses from molecular absorption along the path. The light from the xenon lamp is very intense,
and includes both the visible spectrum and ultraviolet and infrared wavelengths.
The light is captured by a receiver and conducted through an optical fibre to the analyser. The fibre allows the analyser to be installed away from
potentially aggressive environments.
The analyser includes a high-quality spectrometer, a computer and associated control circuits. The spectrometer splits the light into narrow wavelength
bands using an optical grating. This can be adjusted so that an optimum range of wavelengths is detected.
The light is transformed into electrical signals. A narrow slit sweeps past the detector at high speed, and a large number of instantaneous values are built
up to form a picture of the spectrum in the relevant wavelength range. This scan is repeated a hundred times a second, and the registered spectra are
accumulated in the computer’s memory while awaiting evaluation.
The absorption spectrum just registered from the light path is compared with one calculated by the computer. The calculated spectrum consists of a well-
balanced summation of the reference spectra for the analysis concerned.
The computer proceeds by varying the size factors for each reference spectrum until it reaches the best possible match. From this the different gas
concentrations can be calculated with high accuracy.
48N NO O
P PO OL LL LU UT TI IO ON N
I IN N
R R R RI I I IG G G GA A A A
49N NO O P PO OL LL LU UT TI IO ON N I IN N V VE EN NT TS SP PI IL LS S A AN ND D L LI IE EP PA AJ JA A
50A AIIR R P PO OL LL LU UT TIIO ON N IIN N R RIIG GA A
1 2 3 4 5 6 7 8 9 10 11 12
C Co on nc ce en ntr tra ati tio on n, , μ μg g/ /m mIIN ND DO OO OR R A AIIR R Q QU UA AL LIIT TY Y
Air pollution is usually associated with the quality of outdoor urban air. However, the health
of humans may be much more affected by air pollution in their living environment – dwelling
and working premises.
In the rooms is limited
of the pollutants
In the rooms is slow
dispersion of emitted
down degradation of the
People of developed countries, especially, residents of cities, main part of life stay
6% of time
5% of time
stay indoor 65% of
89% of time
52IIN ND DO OO OR R A AIIR R Q QU UA AL LIIT TY Y
A common air filter, being cleaned with a
Spider plants (Chlorophytum comosum)
absorb some airborne contaminants
53IIM MP PO OR RT TA AN NC CE E O OF F T TH HE E V VE EN NT TIIL LA AT TIIO ON N
V Ve en nt ti il la at ti io on n m mo od de es s: :
Intensive ventilation – air
exchange by force with devices
Infiltration – limited non-control air
exchange (through chink, opening, door,
Natural ventilation – air exchange by
natural flow through special openings
Natural ventilation, affected
Natural ventilation flows
by wind and chimney
ventilation systemS SIIC CK K B BU UIIL LD DIIN NG G S SY YN ND DR RO OM ME E
Sick building syndrome (SBS) is a combination of ailments (a syndrome) associated with an individual's place
of work (office building) or residence. A 1984 World Health Organisation report into the syndrome
suggested up to 30% of new and re-modelled buildings worldwide may be linked to symptoms of SBS. Most
of the sick building syndrome is related to poor indoor air quality .
Causes of the syndrome :
Products of fuel
(bacteria, fungi, viruses)
Noxious vapours by chemicals
(glue, paint, etc.) used in
Building occupants complain of symptoms such as sensory irritation of the eyes, nose, throat; neural-toxic
or general health problems; skin irritation; nonspecific hypersensitivity reactions; and odour and taste
In most cases, SBS symptoms will be relieved soon after the occupants leave the particular room or zone.
However, there can be lingering effects of various neurotoxins, which may not clear up when the occupant
leaves the building. Particularly in sensitive individuals there can be long-term health effects.
55C CO ON NS SE EQ QU UE EN NC CE ES S O OF F T TH HE E IIN ND DO OO OR R
P PO OL LL LU UT TIIO ON N IIN N T TH HE E W WO OR RL LD D
Mortality, fatal cases
per one million
56T TH HA AN NK K Y YO OU U F FO OR R A AT TT TE EN NT TIIO ON N