Roofing industry asserts that chrysotile asbestos is safe for use
View(s):The industrial lobby opposing the proposed Sri Lankan ban on chrysotile asbestos has been able to come up with scientific proof that this form of asbestos is not unsafe for human habitation, and thus should not be banned.
In a media release, the Chamber of Construction Industry offers an explanation from Prof. Ravindra Fernando, Chairman, National Dangerous Drugs Control Board, Faculty of Medicine, University of Colombo. He says: “The latest scientific evidence published internationally, strongly supports that Chrysotile is significantly less hazardous than the amphibole forms of asbestos (e.g. crocidolite and amosite) which are not imported to Sri Lanka and when properly controlled and used, chrysotile asbestos in its modern day high-density applications does not present risks of any significance to public and/or workers’ health. Therefore, Sri Lanka should not ban the use of chrysotile asbestos.”
The chamber along with the Chrysotile Information Centre of Sri Lanka (CIC) recently presented the findings of two in-depth studies conducted by the National Building Research Organisation (NBRO) and the University of Moratuwa on Chrysotile roofing products titled – ‘Air-Pollution from Chrysotile Fibre in Roofing Products in Sri Lanka’ and ‘A Comparison of Substitutes for Chrysotile Fibre Cement Roofing Sheets’. They were presented at a conference in Colombo last week.
The first study by the NBRO, reviewed conditions in both the working (ambient) and general environment, the chamber media release said. The NBRO carried out the study focusing on chrysotile fibre exposure in three main areas – manufacturing sites, construction sites and demolition sites and houses – where Chrysotile cement roofing sheets are used.
According to H.D.S. Premasiri, Senior Scientist at Environmental Studies and Service Division, NBRO, “All the exposure levels of chrysotile fibres in all three studies are much below internationally-recognised safety thresholds limit [OSHA (Occupational Safety and Health Administration) Standard of Permissible Exposure Limit (PEL)] which is 0.1 fibre per cubic centimetre in all three studies”.
The second study, conducted by the University of Moratuwa involved a comprehensive, comparative analysis of Chrysotile fibre cement roofing sheets and the proposed alternative fibre roofing sheets.
It was conducted under the supervision of Prof. Asoka Perera, Professor of Civil Engineering at the University, a recognized expert on cement and concrete, and an authority on the subject of developing alternative materials to Chrysotile cement roofing.
Prof. Perera stated, “The purpose of this study was to understand the quality differences of alternative roofing materials versus chrysotile cement roof tiles. The results revealed that non-asbestos fiber cement roofing are nearly two times weaker than chrysotile asbestos sheets, they must be replaced frequently, and the total life cycle cost is comparatively higher than Chrysotile Cement roofing sheets.”