Asbestos refers to a set of six naturally occurring silicate minerals. It is found in mines around the world and has been used commercially for its heat resistant and insulating properties. However, it is now known to be dangerous to human health. The three most common types are chrysotile, amosite, and crocidolite. Asbestos fibers are insoluble and do not degrade, making inhalation hazardous. Its use has declined but still poses health risks where it remains in buildings and other materials.

1. Presentation On

2.  Asbestos includes chrysotile, amosite, crocidolite,
tremolite asbestos, anthophyllite asbestos, actinolite
asbestos,and any of these materials that have been
chemically treated
 a fabric woven from asbestos fibers, formerly used
for theater curtains, firefighters' gloves, etc

3. Asbestos is naturally found with a set of Six Silicate
minerals which has some characteristics for using in
commercial sight
It’s used in certain products, such as building
materials and vehicle brakes, to resist heat and
corrosion

4.  HISTORY
The first recorded use of the word asbestos is by Pliny the Elder in the 1st
century ad, although the substance itself was known as early as the
2nd century bc. The Romans made cremation cloths and wicks from it,
and centuries later Marco Polo noted its usefulness as cloth. Asbestos
se in human culture dates back at least 4,500 years, when evidence
shows that inhabitants of the Lake Juojärvi region in East Finland
strengthened earthenware pots and cooking utensils with
the asbestos mineral anthophyllite.

5.  HISTORY
The word asbestos comes from the ancient Greek
(ἄσβεστος meaning "unquenchable" or
"inextinguishable“.
One of the first descriptions of a material that may have
been asbestos is in Theophrastus, On Stones, from around
300 BC, although this identification has been questioned

6. Source ofASBESTOS Asbestos is not made, it is mined.
Different colors of asbestos can be
found in mines all across the world.
White asbestos, called chrysotile,
comes from mines in Europe and
United States. Brown asbestos,
amosite, is commonly found in
African mines. Blue asbestos,
crocidolite, is found in South Africa
and Australia. Because of this
mineral's abundance and the low
cost of obtaining it, no attempt to
artificially synthesize it has ever
been made

7. Something
About
ASBESTOS

8. Manufacturing Process of Asbestos
 Asbestos is obtainable by various underground mining methods, but the most common method
is open-pit mining. Only about 6 percent of the mined ore contains usable fibers
 The fibers are separated from the ore by crushing, air suction, and vibrating screens, and in
the process are sorted into different lengths, or grades.
 The most widely used method of grading, the Québec Standard Test Method, divides the fibers
into seven groups, the longest in group one and the shortest, called milled asbestos, in group
seven. The length of the fibers, as well as the chemical composition of the ore, determines the
kind of product that can be made from the asbestos. The longer fibers have been used in
fabrics, commonly with cotton or rayon, and the shorter ones for molded goods, such as pipes
and gaskets

9. Producing Nations

10.  Chrysotile
 Amosite
 Crocidolite
 Tremolite
 Anthophyllite

11.  Chrysotile
This is the most commonly
used form of asbestos and can
be found today in roofs, ceilings
walls and floors of homes and
businesses. Chrysotile asbestos
also was used in automobile brake linings, pipe
insulation, gaskets and boiler seals. Although it is more
prevalent, some studies show it takes more exposure to
chrysotile than other types of asbestos to develop related
diseases

12.  Amosite
This is known as brown
asbestos, and it originates
mostly in Africa. It was used
most frequently in cement
sheet and pipe insulation.
It can be found in insulating
board (which contained up to 40 percent asbestos),
ceiling tiles and in thermal insulation products. Like the
other forms of amphibole asbestos, it has needle-like
fibers

13.  Crocidolite
This is blue asbestos and its known
for having the best heat resistance.
Mined mostly in South Africa,
Bolivia and Australia, this is seen
as the most dangerous type of asbestos.
Crocidolite was commonly used to insulate steam
engines, and it was found in some spray-on coatings, pipe
insulation and cement products

14.  Tremolite
This is not used commercially, but
it can be found as a contaminant in
chrysotile asbestos, vermiculite
and talc powders. It was
occasionally found as a
contaminant in certain asbestos-containing
insulation products, paints, sealants and roofing
materials. Tremolite can be white, green, gray and even
transparent

15.  Anthophyllite
This type was mined primarily
in Finland and displays a
gray-brown color. It was not
commercially used and was
rather found as a contaminant.
Anthophyllite was most commonly found in
composite flooring

16. Asbestos- the combined determination of naturally occurring
fibrous silicate minerals that exist in the form of bundles of
fibers. The length of the fiber bundles can be up to several
centimeters. The fiber diameter may be varied, but
generally no greater than millimeter size. They
are resilient, physical and chemical stability,
high tensile strength.

17. Stability of Asbestos in the environment and its biological
behavior in governed by such of its properties:
-Fiber length and Diameter
-Surface are
-Chemical nature
-Properties of surface
-Stability of the mineral in the biological environment

18. Physical Properties
 Fibrous forms and non-fibrous forms of a mineral may occur in
the same deposits. That would make sense when one considers
how asbestos is formed. It would seem very likely that
temperature and pressure might be sufficient to
metamorphose completely some but not all of the igneous rock
into the asbestos form
 two distinct groups: chrysotile (from the Serpentine group);
and amosite, crocidolite, tremolite, actinolite and
anthophyllite (from the Amphibole group). OSHA defines an
asbestos fiber as having a length > 5mm and a length:width
ratio of 3:1. EPA, on the other hand, defines a particle as a fiber
if the ratio is 5:1 length:width when analyzing bulk samples.

19. Physical
Properties
Asbestos is represented as two main groups minerals
and serpentine amfibol differing in type crystal
structure.
When processing the fiber bundles
Can be torn into smaller pieces, some
Of which have a size less
than a micron

20. Asbestos fibers are insoluble in water and organic solvents
and are nonflammable. While the serpentine chrysotile is
soluble in acid, the amphiboles amosite, crocidolite and
anthophyllite are resistant to acids. Interestingly enough,
most asbestos minerals have non-asbestos counterparts
with identical chemical compositions. In the case of
tremolite and anthophyllite, the word "asbestos" is added
after the mineral name to distinguish it from the non-
asbestos form
Chemical Properties

21. Chemical Properties
Asbestos fibers have no detectible odor or taste. They
are all solids that do not move through soil and are
insoluble in water. Its color will vary according to type,
and metallic composition. Crocidolite, which has iron
and sodium as its only metallic elements, is the most
colorful, adorned in a range of colors including shades of
lavender, blue and green. In general, asbestos-containing
iron may display a green color ranging from a hint of
green to solid green depending upon the amount of iron
present

22. Chemical Properties
Tremolite contains no iron, but is part of a continuous
mineral series with actinolite, in which iron and
magnesium can freely substitute with each other. As a
result, some specimens of tremolite may show a hint of
pale green. Chrysotile and tremolite, which in pure form
contain no iron, tend to be white, together with actinolite
and anthophyllite are grouped together as "white
asbestos" and classified as UN2590 (under the United
Nations chemical ID numbering system).

23.  It is vital to ensure that students do not
come in contact with asbestos as it can cause
a range of deadly illnesses including lung
cancer
 According to the World Health Organization,
such asbestos-related diseases kill 107,000
people each year around the world
 DISADVANTAGE OF ASBESTOS

24. Asbestosis is caused by skin damage with the lung area, due to
asbestos fibers materials lodging right now there. Exposure to
asbestos may also result in mesothelioma, the unusual cancer
with the upper body, heart as well as stomach coating

25. USES OF ASBESTOS FIBER
Asbestos is a nonmetallic mineral fiber, which is
nonflammable. The fiber is woven into fabrics and used for
theater curtains and industrial uses where flame-resistant
materials are needed. The fibrous form of several minerals
and hydrous silicates of magnesium. The name may also be
applied to the fibrous forms of calcium and iron. Asbestos
fibers can be molded or woven into various fabrics.
Because it is nonflammable and a poor heat conductor,
asbestos has been widely used to make fireproof products
such as safety clothing for fire fighters and insulation
products such as hot-water pipin

26. USES OF ASBESTOS FIBER
Fire-resistant and non-asbestos fiber cement boards
Asbestos fiber wire
Duct Asbestos insulation: asbestos paper

27. Abestos yarn is made of white, clean
chrysotile Twisted Asbestos Fiber
USES OF ASBESTOS FIBER

28. THANKS
TO
ALL
Mohammad
Samee
SHAKIR
Mahadi
Hasan
SHAWN
Tamzid
Hayder
TAWRT
Sikder
Mahamud Hasan OVI

29. ANY……?????????