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
|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 of Appeals 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|
|6||Absorption of Rain and Wind Noise||Good (deadens these noises)||Poor||Poor|
Required in Production
|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|
|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.|