The risk rating given to floor tiles is based on a conservative assumption; whereby if there is uncertainty as to whether a product contains asbestos, it is assumed that it does until determined otherwise. Not all old floor tiles or sheet flooring contain ACM, but until tests show otherwise we assume they do.
If floor tiles were installed between 1920 and 1960, there's a good chance they contain asbestos because most flooring tiles manufactured during this period did. If the tiles were installed between 1960 and 1980, there's a possibility they contain asbestos. Typically, floor tiles may contain from 2% to 6% chrysotile asbestos.
The five schools referred to in the Sunday Times article were all built in the 1970s so the probability that they contain asbestos is low. However, it is important to note that the mastics or adhesives used to install vinyl tiles may also contained asbestos as a binding agent. Asbestos fibres in adhesives are unlikely to become airborne unless a high speed abrasive tool is used to disturb the tiles or adhesive, such as an electric drill or electric saw.
The risk rating that has been awarded by the inspector does not acknowledge that while the tiles are undisturbed and properly maintained it is extremely unlikely that any asbestos fibres would be released.
Please also note that DoE works closely with BMW in regards to all asbestos related matters, and we will be raising this issue at the next Steering Committee.