| 1. WHAT IS ASBESTOS ?
- Asbestos is a naturally occurring mineral found in underground rock formations. For commercial purposes, it is recovered by mining and rock crushing. Fine fibres, invisible to the eye, are present in the air and water in every region of the globe. Hence, all of us may be inhaling and also ingesting them through drinking water every day. There are two different varieties of asbestos (i) Chrysotile variety and (ii) Amphibole variety. Amphibole variety comprises of Crocidolite, Amosite, Tremolite, etc. Only Chrysotile variety is in production and use for the past two decades.
- Only Chrysotile variety (white asbestos) is in commercial use now. Indian asbestoscement sheet and pipe manufacturers import all their requirements of chrysotile fibres from Canada, Brazil, Russia, Zimbabwe and Kazakhstan for production of AC sheets and pipes. Chrysotile asbestos is also mined in India in very small and insignificant quantities which are of no consequence or relevance to our asbestos-cement production. The other varieties of asbestos known as amphiboles (crocidolite, amosite, tremolite, etc) which were considered rather unsafe, have been prohibited all over the world including in India. Wherever asbestos is produced or used in products, only Chrysotile variety is permitted now.
- Chrysotile asbestos fibre, (composed mainly of magnesium and silica), is a great reinforcing agent. While its tensile strength is greater than steel, it has other rare and highly valued fire-retardant, chemical-resistant and heat-insulating qualities. In fact it is a magic mineral.
2. WHAT ARE ASBESTOS-CEMENT (AC) PRODUCTS ?
- AC products are made with a mix of chrysotile fibres (about 8-9%), cement (about 40%), Fly Ash (about 30%), the rest being wood pulp and water. Over 90% of asbestos fibre imports of India go in to AC sheet and pipe production.
- AC Sheets have been used in India for over 70 years. Being weather-proof and corrosion resistant, these sheets are practically ageless and maintenance free, whereas metal sheets corrode and deteriorate with age and exposure. (See chart for comparison).
- AC Sheets have also proven to be the most cost effective, easy-to-install, strong and durable roofing material for warehouses, factories, low-cost housing, and practically any structure needing a roof. Apart from India, Russia, China, Thailand, Brazil are some of the largest users of AC Sheets.
- AC sheets and pipes, being corrosion and erosion-free, once properly laid and jointed, need no maintenance or replacement. They are also very cost effective
- AC products, which consume low energy in manufacture and do not in any way deplete the natural resources, meet the needs of the country in its developing economy in the context of rapidly rising population and limited resources.
- AC products are manufactured under (ISI) licence strictly conforming to the standards of Bureau of Indian Standards. IS 459/1992 for Corrugated Roofing Sheets, IS 2098/1997 for Building Boards, IS 2096/ 1992 for Flat Sheets and IS 1626 (Part III)/ 1994 for Roofing Accessories. AC Pressure Pipes are covered by IS 1592/1989.
3. EXPLAIN THE NEGATIVE REPORTS ON ASBESTOS :
- The bias against the use of asbestos in a
few countries is due to the adverse
Western media coverage relating to
altogether different usages of asbestos in
the past in those countries i.e. sprayed
on asbestos and friable low-density
asbestos insulation used under
uncontrolled conditions at that time due
to lack of adequate scientific knowledge.
Though these particular usages have since
been discontinued, the claims relating to
the past keep appearing in the media
resulting in general confusion. (there is
no such usage in India)
- But, once the scientific research into the
risks of asbestos was set in motion,
development and installation of pollution
control systems took place, enabling the
asbestos mining and asbestos cement
industries to maintain safe and acceptable
levels of dust pollution at the work places.
- Once the permissible levels of exposure
were defined, the Governments have
stepped in and laid down pollution control
regulations and the mechanisms to enforce
their compliance. Compliance with these
regulations and standards assure the
workers in asbestos-cement industries a
risk-free environment.
For the consumer, the Asbestos Cement
products were and are always safe as the
fibres are locked in layers of cement–fly
ash matrix.
4. WHAT IS THE SITUATION IN INDIA ?
- In India, only the chrysotile variety of
asbestos, which is considered safe, is used
in asbestos-cement products, namely,
sheets and pipes. The fibres are mixed
and bonded with cement and other raw
material, with no chance of escaping into
the atmosphere on normal usage.
- Workers in asbestos-cement product
industry in India have not had any adverse
health effects in spite of decades of
service, there being no risk of exposure
to asbestos dust because of pollution
control measures installed in the factories.
Health of the workers is closely monitored
as per directives and regulations of the
government agencies.
- There is no risk whatsoever in living or
working under the AC roof, as asbestos
fibres are bonded (locked in) with cement
and cannot get released in to the
atmosphere.
Dr F.D. Pooley’s Report of 2004 concludes
“asbestos fibres locked in to high density
products like asbestos-cement have been
rendered safe by the attendant chemical
process …. Chrysotile fibres have been so
altered chemically and structurally that
it is no longer justifiable that they should
continue to be defined as chrysotile”
- Transportation of drinking water in AC
pipes is absolutely safe as confirmed by
the World Health Organization. Ingested
asbestos does not pose any health risk.
Indian climatic conditions never required
the type of asbestos spraying and
insulation, at one time common in the
West. Thus, the health hazards and risks
associated with the past asbestos fibre
usage in the western countries, have
nothing to do with the current usage of
asbestos products or applications in India.
In India, Asbestos Cement sheets have
been extensively used by Indian Railways
for over 60 years to provide safe and ideal
form of roofing to thousands of Railway
Platforms across the country where over
10 million people step everyday. It is
noteworthy that AC Sheets have withstood
the test of time with no reported risk/
casualty to the Indian traveller nor has
there been any adverse effect on the local
environment.
Another major consumption of AC Sheets
is in the roofing of Food Corporation of
India godowns where millions of tons of
food grains are stocked. The above two
examples are testimony to the fact that
Asbestos Sheets are absolutely safe to use.
It is worth noting that India uses only about
16-18% of the asbestos produced in the
world. The rest is used in other countries,
where, obviously, it is accepted as safe.
The Russian Government Decree No. 869
of July 1998 stated “Excessively hasty and
not well founded refusal to use chrysotile
asbestos does not have a sufficient medical
and biological substantiation and can bring
about serious negative consequences for
economy of a great number of countries.
The ban in some countries did not consider
national social and economical interests,
scientific research results nor the latest
scientific and technical achievements
regarding production and use of chrysotile
asbestos”.
5. WHAT ARE THE POLICIES OF GOVERNMENT OF INDIA ON ASBESTOS?
- The Government of India has constituted
various expert committees to study the
asbestos industry and having been satisfied
that asbestos does not actually pose a
health risk to the workers at the
manufacturing plants so long as the work
place pollution controls were in place, or
to the public who use the asbestos-cement
products, the Ministry of Industry,
Government of India, in July 1997, has in
fact de-licensed the industry, allowing
any person to set up a factory without the
need for an industrial licence from the
ministry.
- Of significance is the National Study on
Work Environment in Asbestos Products
Manufacturing Industry conducted by the
Central Labour Institute, Ministry of
Labour, Govt. of India in the year 2004/
05 in which 702 workers exposed to
asbestos had participated. The duration/
period of their exposure ranged from 6 to
over 20 years. The conclusion of the Study:
“No established case of asbestosis was
detected during the Study”.
- The Ministry of Environment, Govt. of India
has been giving approvals for setting up
new units for manufacture of asbestosbased
products after evaluating the
environmental issues and stipulating
various safeguards.
- The Ministry of Industry, Ministry of
Labour, Ministry of Environment, Ministry
of Consumer Affairs, Bureau of Indian
Standards, et al. have laid-down
regulations, standards, guidelines and
recommendations specific to the asbestos
industry, in line with those of International
Labour Organization, World Health
Organization and other bodies. The
Central and State Pollution Control
Boards, Labour and Factory Inspectors
also regularly monitor the factories’
compliance with the mandatory safety
standards and pollution control levels.
- The Central Ministries of Industry,
Environment, Labour, Central Pollution
Control Board, and Ministry of Consumer
Affairs and Bureau of Indian Standards
have concluded that the asbestos-cement
industry can operate in a safe environment
under the laid-down pollution control
levels.
- In India, asbestos-cement industry strictly
implements the provisions and
recommendations of International Labour
Organization’s Convention No. 162 titled
“ Safety in the Use of Asbestos “ to ensure
safety in the use of asbestos.
6. ARE THERE ANY COURT RULINGS ON ASBESTOS USAGE ?
- Concerns caused by the past medical
findings in the Western countries,
when asbestos applications were
indiscriminate and bereft of pollution
controls, resulted not only in anti-asbestos
media campaign and litigation, but also
led some environmental activists and NGOs
to the Courts appealing for effective
remedies.
- The Hon'ble Supreme Court of India has,
in Jan 1995, disallowed one such appeal
and permitted the continued usage of
asbestos and asbestos products, as the
petitioners failed to produce evidence to
prove that asbestos-based items or their
manufacturing process in India were
dangerous to health.
- After considering a strong case by the
powerful Environmental Protection
Agency, the United States Court of Appeals
has, in 1991, rejected an appeal for
phasing out asbestos-cement and other
asbestos based products in USA, again for
lack of evidence to warrant such a
prohibition.
7. ARE ASBESTOS AND ASBESTOS CEMENT PRODUCTS STILL USED IN OTHER COUNTRIES ?
- There is no ban on production or usage of
asbestos-cement sheets or pipes in USA
and Canada and 80% of the other world
nations. Very few countries have
regulations restricting use of asbestos
based products most of which had, in any
case, been phased out much earlier due
to high economic development, improved
standards of living and changed life styles.
- The USA still imports AC pipes for water
transportation. The USA also uses some
quantities of asbestos for use in the space
rocket launching equipments.
- In 2001, Canada has re-introduced
asbestos to make asphalt-asbestos
compound for re-paving of the roads, for
more flexibility, resistance and for
reducing fissures on the road surface.
- As said earlier, even today, Russia, China,
Thailand, India, Brazil, Indonesia,
Ukraine, Vietnam, Mexico are among the
largest users of AC sheets and other
products.
AC products are environment friendly
inasmuch as they consume a large volume
of (30% as raw material) Fly Ash, which is
a waste generated by power plants in the
country.
- AC products, in their manufacture,
consume 36 times less energy as compared
to competing alternative metal sheets and
metal pipes.
- About 85-87% of Chrysotile Asbestos
produced worldwide is consumed by
countries other than India. India uses
barely 12 to 15% of world’s chrysotile
asbestos fibre production. This goes to
prove that AC sheet and pipe production
and usages of these products are very
much prevalent in much of the world.
This asbestos production and usage in most
countries confirms that these products do
not cause the health problems as
propagated by some zealots and industrial
competitors. There are activists
everywhere who pursue some issue or the
other, often with inadequate research or
deliberately-fed misinformation for their
personal gains. Asbestos is merely one
such issue, which 80% of the world nations
chose to ignore.
8. ARE WORKMEN INSTALLING AC ROOF AT RISK OF EXPOSURE TO ASBESTOS?
- No certainly not, when the recommended
work practices are followed while on the
job, like using only hand driven tools – and
not power driven tools.
- A typical study was conducted while
handling, cutting & installation of asbestos
cement roofing sheets. The typical test
results show the fibre concentration in air
sampling is found to be far below the
stipulated safe level.
- In a Paper (1992) Prof. L. Elovskaya
reported that “ fibres emitted from
asbestos cement products in the course
of their exploitation (handling) are
significantly different … their surface
characteristics, composition and
crystal structure all change “ meaning
that such fibre emissions, if there are
any, do not pose any health risk.
- Prof. JA Hoskins / JH Lang (2004)
reported “ Around 200 studies have
shown that exposure to any chrysotile
fibres, if released during the use and
handling of this high density product
(ac sheets/pipes) present no
measurable risk to health.
9. IS IT DANGEROUS TO LIVE OR WORK
UNDER AN ASBESTOS CEMENT ROOF?
- Not at all. There is no risk, whatsoever,
to health as the asbestos fibre content in
AC Sheets is very little (about 7-9%).
Moreover, the asbestos fibres being
locked-in and bound with cement, there
is no possibility of these fibres escaping
(from the products) into the ambient air.
- Several measurements and studies have
confirmed this fact (see 8 above).
10. IS PUBLIC AT RISK DUE TO
WEATHERING OF ASBESTOS CEMENT
PRODUCTS ?
- Asbestos cement sheets do not decay or
rot because of the inherent properties of
asbestos fibre and cement. These do not
crumble due to continued exposure to the
elements or due to age. There is no
evidence that people living under
asbestos-cement roof, or the general
public living around asbestos-cementroofed
buildings or factories producing
asbestos cement products have been
specifically affected in any manner (see
8 above).
- In fact studies have concluded that there
is no increase in asbestos dust
concentration in the near vicinity of
asbestos cement roofing.
Felbermayer W and Ussar MB (1980) Study
Report in Austria says “A comparison of
the asbestos fibre concentrations in those
areas with and without asbestos-cement
roofing…lead to the conclusion that there
is no statistically significant connection
between the use of asbestos cement
materials and the asbestos fibre
concentrations found in the various
measurement areas ”
11. IS IT WRONG TO USE AC PIPES FOR
CARRYING DRINKING WATER ?
No. Even the World Health Organization
has approved the usage of AC pipes for
drinking water. As stated earlier, the
most health-conscious USA uses AC pipes
for drinking water transportation.
12. OME QUOTES FROM THE WEST
ABOUT ASBESTOS?
- SThe Times, London, 18 Sept 2001, quoting
Mr. Richard Wilson, Professor of Physics
at Harvard University in Cambridge,
Massachusetts, USA, reported that
“asbestos is the best insulator we know
of, and not to use it because of hysterical
public health reasons, is absurd”.
- The Wall Street Journal, USA, 19 October
2001, in an article captioned “EPA comes
clean on Asbestos”, reported “ Faced with
a public health scare ………the EPA
(Environmental Protection Agency of the
USA) decided to cough up the truth about
asbestos. Its officials bent over backward
to get out the message that asbestos was
harmful only if breathed at high levels and
over sustained periods of time” The north
Tower contained 40 floors of asbestos. The
EPA repeated that the public was not at
any real risk from the asbestos released
from the collapse of the WTC north tower
and swirling around downtown Manhattan.
- After Sept 11, 2001 collapse of WTC
towers, Prof. Art Robinson, founder of the
Oregon Institute of Science and Medicine,
said “ asbestos was an early victim of junk
science and enviro-fear propaganda.” Had
the (top floors) contained asbestos, the
towers would have stood for four hours,
saving 5000 lives.
- The USA Geological Survey Fact Sheet FS
–12 –1 of March 2001 reports “
There have been thousands of applications
for asbestos. Most were viewed as
practical solutions to difficult problems.
For instance, (i) asbestos helped make the
braking systems in automobiles much more
dependable, (ii) it enabled the production
of inexpensive cement-based water supply
pipes.
- La Presse, Canada, May 18,2001 has
quoted Katherine Glasson, press officer for
the Minister of Transport as having said
“this material is not dangerous” The paper
also said “ the Minister of Transport
estimates to use 100,000 tons of asbestosasphalt
for the repaving of its road
network this year as compared to 17,000
tons last year” .
SOME POPULAR MISCONCEPTIONS
| MYTHS: |
FACTS: |
| Asbestos cement
is dangerous
material. |
Asbestos cement is
completely safe. It is
not corrosive, reactive,
ignitable or toxic. |
| Inhalation of
even one fibre of
asbestos is
harmful. |
Thousands of asbestos
fibres, invisible, are
inhaled by us everyday
from natural resources,
and cleared off by
natural clearance
mechanisms without
any harm.
Asbestos cement has
only 7-9% asbestos fibre
that is bound with
cement and cannot be
released into air. |
| Asbestos cement
water pipes
cause colonic
carcinoma and
other diseases. |
Asbestos fibres in water
are ingested without
any harm whatsoever.
Therefore the AC water
pipes pose no threat. |
| Developed
countries have
banned asbestos
cement products.
Only poor
countries need it |
80% of World national
continue to use
Asbestos cement
products. |
| Asbestos cement
production is
banned in the
USA |
The US Court ofAppeals
rejected a proposed
ban on scientific
grounds.
Asbestos-cement
products are not
banned in the USA |
COMPARATIVE CHARACTERISTICS OF VARIOUS ROOFING MATERIALS
| S.No. |
Characteristics |
Asbestos Cement Sheets |
Corrugated Galvanized Iron Sheets (CGI) |
Aluminium Sheets |
| 1 |
Life Span(Years) |
50 (Min) Non-Corrosive |
10-15 |
N.A. |
| 2 |
Maintenance |
NIL |
Every 3-5 Years |
NIL |
| 3 |
Fire Rating |
Retardant |
Tendency to twist and melt |
Tendency to twist and melt |
| 4 |
Thermal Insulation |
Good |
Poor |
Poor |
| 5 |
Accoustic Rating |
Good |
Poor |
Poor |
| 6 |
Absorption of Rain and Wind Noise |
Good (deadens these noises) |
Poor |
Poor |
| 7 |
Energy Consumption
Required in Production
(KWH/SQ.M) |
1.0 |
36.6 |
38.0 |
| 8 |
Man Power
Employment Potential |
Intensive |
Low |
Low |
| 9 |
Wind Resistance
When Installed |
Good |
Poor |
Poor |
| 10 |
Weather Effect |
None |
Corrosion at drilled holes and where galvanizing is cracked |
Surface oxidation |
| 11 |
Bimetallic Reaction |
None |
None |
Present in contact with
concrete and other metals
in presence of moisture |
| 12 |
Condensation |
Low and will not effect sheet |
High and will effect sheet |
High and will result in corrosion |
| 13 |
Effect of High Winds |
Minimum |
Unacceptable rattling sound |
Rattling sound |
| 14 |
Noise Level |
Low |
High |
High |
| 15 |
Protective Coating |
Not required |
Not required |
Required to avoid direct
contact with cement,
limesoil, Iron, copper, etc. |
| 16 |
Storage |
Can be stored in open space at work site |
Needs closed godown for storage to avoid weather assaults |
Needs closed godown for storage to avoid weather assaults |
| 17 |
Coverage Efficiency |
Approx. 50% higher than GC and Aluminium Sheets. |
Effective laid area becomes only 67% as compared to AC Sheets |
Effective laid area becomes only 67% as compared to AC Sheets. |
| 18 |
Cost |
Low |
High |
Highest |
|