A perspective on ´Fibre based corrugated cement sheets´

John Nicodemus, Executive Director, The Fibre Cement Products Manufacturers? Association
There is wide spread misunderstanding about use of asbestos and products made out of Asbestos. In few of the countries mainly in Europe it has been banned, however in many other countries like U.S.A., Canada the use is still allowed. We were in Q &A session with John Nicodemus of ?The Fibre Cement Products Manufacturers? Association? a body which represents the cement based corrugated sheet manufacturers. He has tried to throw light on some of the facts and myths associated with asbestos cement products.

What is Chrysotile Asbestos Fibre?
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. ?Asbestos? was a commercial term given to collective group of 6 naturally occurring minerals whose crystals occur in fibrous forms. Though commonly referred as ?Asbestos? these 6 silicate minerals come from two distinct groups and are chemically and mineralogically different. There are two distinct varieties of asbestos (i) Serpentines (Chrysotile white asbestos) and (ii) Amphibole variety comprises of amosite, (brown asbestos), crocidolite (blue asbestos), tremolite, actinolite, and anthophyllite, Mining, production and usage of Amphibole variety of asbestos have been prohibited all over the world for decades now as they are considered un-safe.

Only Chrysotile variety of fibre (white asbestos), which is considered safe to use under controlled conditions, is in commercial use now. Indian asbestos cement sheet and pipe manufacturers also use only chrysotile variety which incidentally is all imported mostly from Russia, Kazakhstan and Brazil. Canada?s and Zimbabwe?s production and exports have become rather insignificant of late.

Chrysotile asbestos fibre is also mined in India in minuscule quantities and so is not of any consequence. 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.

Bio-persistence studies have been carried out on number of different respirable particles. Regarding asbestos fibres, it was repeatedly demonstrated that chrysotile displays low bio-persistence, as opposed to the amphibole asbestos fibre types which display exceedingly long bio-persistence.

What are Fibre-Cement (AC) products?
AC products are made with a mix of chrysotile fibres (7-9 per cent), cement (about 40 per cent), Fly Ash (about 30 per cent) and the rest being wood pulp and water. Over 95% of chrysotile asbestos fibre imports of India go in to chrysotile-fibre cement sheet and pipe production.

AC Sheets have been used in India for over 80 years. Being weather-proof fire resistant, non-combustible, and corrosion resistant, these sheets are durable practically ageless and maintenance free, whereas metal sheets corrode and deteriorate with age and exposure.

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 specifications 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.

Explain the negative reports on Asbestos Fibre.
The bias against the use of asbestos fibre in a few countries is due to the adverse Western media coverage relating to altogether different usages of Amphiboles ? brown and blue 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.

The severe health problems arose in the distant past in the Western countries because of use of mixed fibres, predominantly blue (crocidolite) fibre in various applications, such as spraying, with dust levels going up to 100s of fibres / cc and beyond. But currently the only variety of asbestos used in chrysotile fibre cement roofing products and pipes is ?chrysotile?.

According to scientific research by Dr David M. Bernstein and the emerging bio-persistence data, chrysotile variety of asbestos, even if inhaled in accepted levels, clears from the lungs within 3 to 11 days. But crocidolite, and other amphibole varieties of fibres may take up to 500 days for clearance from the lungs because of very high iron content and therefore have been determined as a major health risk and consequently banned all over the world. But the safer chrysotile variety?s usage is allowed.

Though these particular usages of amphibole varieties 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 or anywhere in the world now).

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.

What is the situation in India?
In India, only the chrysotile variety of asbestos fibre, 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-fibre-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.

India uses only about 20% of the chrysotile asbestos produced in the world. The rest is used in several other countries, where too, these chrysotile fibre cement products are accepted as ideal and 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?.

Are there any court rulings on Asbestos Fibre 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.

Again in January 2011, the Hon?ble Supreme Court turned down another petition to ban asbestos for lack of evidence about the health risks arising out of asbestos.

Are Asbestos and Asbestos-Fibre-Cement products still used in other countries?
There is no ban on production or usage of asbestos-fibre-cement sheets or pipes in USA and Canada and in about 77 per cent of the other world nations. Very few countries have regulations restricting use of asbestos based products due to high economic development, improved standards of living and changed life styles. The USA and Canada still import AC pipes for water transportation. The USA also uses some quantities of asbestos for use in the space rocket launching equipments. According to US Geological Survey, during the year 2014, even some of the countries in the European Union have imported small quantities of asbestos for specific uses. These countries include Spain, UK, Romania, Slovakia, Peru, South Korea, Czech Republic, Austria, Bahrain. In 2013, France, Germany, Italy, Argentina had imported some asbestos. Obviously for usage in some critical applications, where no effective substitute to chrysotile could be found in spite of researches.

Canada and USA are said to still import chrysotile asbestos pipes for potable water carriage.

Is it wrong to use Asbestos Fibre 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 and Canada use AC pipes for drinking water transportation.

Inputs are given by John Nicodemus, Executive Director, The Fibre Cement Products Manufacturers? Association

Extract of the policies adopted by Government of India on use of asbestos The Ministry of Industry, Government of India, in July 1997, has in de-licensed the industry. The only requirements are approvals from the State Pollution Control Boards and the Central Ministry of Environment, Forests & Climate Change.

The National Study on Work Environment in Asbestos Products Manufacturing Industry was 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 asbestos based 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, etc. 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.

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.

And also complies with the Model Rules of the Minstry of Labour relevant to this industry under the Factories Act.

Table 1: Some Misconceptions

Comparison between AC pipes and others