Hyperspectral discrimination of asbestos-cement roofing

Asbestos-containing products are harmful to human health, and therefore their usage and production was banned in 55 countries, including EU. Since asbestos-cement roofing accounts for 90% of asbestos used in the world today, an important issue is to use remote sensing data for asbestos identification and mapping. The objective of this study was to determine the possibilities of discrimination of asbestos-cement roofing (ACR) from other roof coverings, based on spectral signatures, and to select the most appropriate wavelengths for classification purposes. Spectral signatures were measured under laboratory conditions for 43 types of roof coverings typical of buildings in Poland with the use of ASD FieldSpec 3 (350-2500 nm). Roofing coverings were varied as to the composition material (metal sheet, ceramic, cement, asbestos-cement, roofing felt), coating (enamelled, lacquered, matt, clayed, polyester), colour, and shape (corrugated, flat). Samples of asbestos-cement roofing were collected during field visits and others were acquired from distributors of building construction materials. Analysis of spectral signatures indicates that there is a possibility of discrimination of ACR from other roof coverings. The optimal wavelengths determined were 410, 550, 670, 740, 870, 990, 1310, 1700, 1840, 2130, 2200, and 2270 nm.