ISSN 2086-5953
2.3.1 Smoke
Smoke is the term normally applied to the visible products of imperfect combustion. Smoke
has the important property that, because of the small size of its particles, it behaves in many ways
like a gas and has the same powers of penetration. The average diameter of a smoke particle is about
0-
0,75 μm. Smoke also sticks to the outside of buildings, for rain will not wash it away, unless the
stone is slightly soluble or very smooth.[3]
Picture 3. Smoke from industry www.majarimagazine.com
2.3.2 Sulfur dioxide
Sulfur dioxide is formed in considerably quantity when coal, coke or certain fuel oils are
burnt. Though it is not so chemically active as sulfur trioxide, hydrochloric acid and the fluorine
compounds which are also liberated during the combustion of coal, it is emitted in much greater
quantity and is thus capable of doing more harm.[3]
Picture 4. Chart of SO
2
at DKI Jakarta in October 2010 www.lapan.go.id
Picture 5. Chart of SO
2
at DKI Jakarta in November 2010 www.lapan.go.id
2.3.3 Carbon monoxide and Carbon
dioxide
Concentration of carbon monoxide from 10 to 70 mg m
3
are common in busy streets; concentration of 120 mg m
3
or more are considered dangerous. Most of it is due to the incomplete
combustion of petrol in internal combustion engines; properly adjusted diesel engines burn a
―lean‖ mixture and produce very little carbon monoxide. Although the incomplete combustion of
coal and coke also produces carbon monoxide, it is doubtful whether enough of this could reach street
level to be a danger to health.[3]
Carbon dioxide is a normal constituent of the atmosphere necessary to vegetable life, but an
unpublished observation from the British Oxygen Company‘s works in Greenwich, where carbon
dioxide has to be removed from the air before it is liquefied, indicates that during the London smog
and fogs of the fifties the concentration of carbon dioxide was well over twice than normal amount. A
sufficiently high concentration, of about 10 or 100 times normal, would accelerate human breathing
and enhance the effects of poisonous gases. It also enhances photosynthesis by plants, which take up
the excess carbon dioxide together with any other noxious gases present.[3]
Picture 6. CO emission source in Australia from 1999-2000 www.npi.gov.au
ISSN 2086-5953
Picture 7. CO emission source from transportation in Australia from 1999-2000 www.npi.gov.au
2.3.4 Nitrogen oxides NO