A view from the National Building Research Organisation (NBRO):

Banning asbestos to save lives

President Maithripala Sirisena recently gave an assurance that he would discuss with the Cabinet of Ministers and arrive at a decision to ban the importation of asbestos roofing sheets into the country by the year 2018.

Asbastos is recognised as a silent killer (srilankanscientist)

This is a step in the right direction. Many countries, including the major producers of asbestos such as Canada, South Africa, UK, Australia, New Zealand, Japan, Italy, Singapore, South Korea, EU, Turkey and 50 industrialized nations have now banned the use of all asbestos products.

WHO studies have revealed that all forms of asbestos –blue, brown and white – pose a health hazard. WHO is unequivocal about the danger posed by all types of asbestos.

Yet, in Sri Lanka, the temptation of a comparatively low-priced tax free construction material is simply too good to resist, though it is at the expense of the health of our people. WHO has claimed that at least 107,000 people die each year from asbestos-related cancers.

As the onset of the disease takes time, there can be a false sense of security if one is immediately not observing any affected people in numbers. The period can be as long as 20-40 years.

Sri Lanka banned the use of one form of asbestos in 1987 though other forms are still widely used. The vision of the statement made by President Sirisena was to enact a comprehensive ban which is in line with WHO recommendations.

The National Building Research Organisation (NBRO) – the mandated institute on building research and as the apex organization committed to research and development, testing and advisory activities within the housing and construction sector – took the initiative to introduce acceptable substitutes for asbestos-cement corrugated sheet, currently in wide use. The NBRO initiative is supported by the experience it possesses in the use of coconut fibre with cement as corrugated roofing sheets in government-sponsored housing schemes in the early 1980’s.With this experience, the NBRO took up the responsibility of evaluating and promoting suitable alternatives to asbestos fibre-based materials.

As a first step, a dialogue was initiated with the relevant stakeholders to evolve a substitution programme for asbestos-cement corrugated roofing sheets and flat sheets. The forum met on 4 September 2015.

Public awareness

There is a lack of awareness among the public about the health hazards posed by asbestos. The long gestation period before the symptoms appear due to inhaling of asbestos fibres makes the users less alert. This fact is being unscrupulously exploited by the manufacturers to convince the public that there is no evidence to say that asbestos sheets cause cancer and mesothelioma.

Moreover, asbestos roofing sheet is an affordable building material.

Its ready availability and the ease of installation make it the obvious choice of the uninformed public. The main argument put forward by manufacturers against substitution is that the construction industry and public will be inconvenienced due to the non- availability of suitable substitutes.

Some of the issues raised at the expert forum are shared here, for public understanding.

1.Not many studies have been done on the occurrence of asbestos-related diseases in Sri Lanka. Most institutions do not have facilities to monitor the release of asbestos fibres to ambient atmosphere and relate it to the incidence of occupational hazards arising from it.Although there are permissible limits of concentration of asbestos fibres in air given in various specifications, even a single fibre which goes into the respiratory system can lead to a fatality.

2.In view of the government’s decision and the increasing number of countries banning asbestos products, it would be futile to permit continued production of asbestos-containing products, even under restrictions, beyond 2018.

On the other hand, it would not be advisable to make the removal of asbestos-cement sheets from existing roofs obligatory, before or after the deadline, until proper disposal facilities are in place since people working and living at removal/demolition sites become vulnerable.

3.Many roofing materials other than asbestos-cement sheets are commonly used in Sri Lanka, with limitations and drawbacks. For example, mining of clay for roofing tiles manufacture leads to environmental degradation; zincalume sheets need additional heat and sound insulation in their applications in roofing and cement tiles are heavy and require more timber for the supporting structure.

These issues should be properly addressed when alternatives to asbestos-cement sheets are considered in detail.

4.The NBRO Consultative Committee scrutinized the range of substitutes numbering to 14 available for corrugated asbestos sheets, which are being used in countries with a ban on asbestos. Some of these, though not critically analysed yet with respect to their cost effectiveness are listed below to dispel the myth that no substitutes are available.

Fibre-cement roofing with synthetic fibres – polyvinyl alcohol (PVA) and polypropylene

Clay tiles – flat and other profiles or traditional round (which does not require very good clay for manufacture)

Coated metal sheet/tiles (Zincalume)

Vegetable fibres in asphalt roofing sheets (Further research and development work needed)

Glass fibre reinforced magnesium oxychloride (MgOCl) cement based tiles(Further research and development work Needed)

6.The construction industry voiced the switch to flat roofs and green building concepts which would bring about a major change and remove the need for asbestos roofing materials.

Policy decision

This may be difficult for immediate implementation.

Some of the above materials may find use in urban areas whereas some are suitable for rural.

In view of the international scenario and the government policy decision it is the duty of the scientific community to examine the possibility of substitutes in conjunction with the locations in Sri Lanka where different substitutes could be adopted for better results.

There are materials suitable as substitutes to flat sheets used in ceilings, partitions and facades. They include:

Fibre-cement using vegetable/cellulose fibres

Wastepaper, optionally synthetic fibres

*Gypsum ceiling boards
*Polystyrene ceilings
*Galvanized/softwood frame with plaster boards or calcium silicate board

Some of the above materials listed under the two categories may be used directly as substitutes for asbestos in the local industry without any change in the machinery presently used for the manufacture of corrugated sheets and flat sheets.

Regional availability of raw materials may make some of them harmonize with the locations.But in the selection of any substitute or alternative material, attention should be paid to environmental safety and health issues, cost effectiveness in production, overall cost in roofing applications, durability and the possibility of replacing existing asbestos-cement sheets without modifications to the roof structure.

Availability of material

Appropriate selection of materials may open new vistas to promote the development of the cottage industry and provide value addition to waste materials by producing vegetable fibre-reinforced cement roofing sheets.

Regulations on environmental safety and on the health and hygiene of workers are in place for the production of asbestos-cement sheets and building materials. However, similar regulations do not exist in respect of installation and demolition of asbestos-containing material. Further, safe disposal methods are not in practice and much environmental pollution is caused as a result.

The International Organization for Standardization (ISO) has issued an International standard on corrugated roofing sheets covering the materials to be used, the profile of corrugation and the manufacturing requirements. Sri Lanka Standards Institution (SLI) has taken action to adopt the international standard as a Sri Lanka standard, which could be used as a guideline in the production and use of asbestos-free roofing sheets.

The following decisions were reached by the Forum to move towards an action plan.

1.Initiate an immediate dialogue with manufacturers on the production of asbestos-free materials for applications in roofing and other areas.

2.Carry out trial production of roofing sheets using alternative fibres which can be applied without changes to existing machinery.

3.Initiate fast-track applied research and development in collaboration with the manufacturers to enable a smooth switch over to asbestos substitution by 2018.

4.Formulate codes of practice and regulations to ensure safety in the installation, demolition and disposal of asbestos-containing materials.

6.Formulate programs for educating stakeholders and providing publicity on the application of substitutes.

7. Suggest the use of alternatives in all school buildings immediately and other government buildings, subsequently.