Asbestos is a naturally occurring fibrous material that has been a popular building material since the 1950s. It is used as an insulator (to keep in heat and keep out cold), has good fire protection properties and protects against corrosion.
Asbestos, from the Greek work “unquenchable” is a group of natural minerals which are fireproof and remarkably resistant to acids and alkalies. It was also discovered that asbestos was a very efficient insulator and could bind together other materials to produce a product of greater strength.
Because asbestos is often mixed with another material, it’s hard to know if you’re working with it or not. But, if you work in a building built before the year 2000, it’s likely that some parts of the building will contain asbestos.
Asbestos is found in many products used in buildings, including ceiling tiles, pipe insulation, boilers and sprayed coatings.
Asbestos – Common Uses
Asbestos was extensively used as a building material in the UK from the 1950s through to the mid-1980s. It was used for a variety of purposes and was ideal for fireproofing and insulation. Any building built before 2000 (houses, factories, offices, schools, hospitals etc) can contain asbestos. Asbestos materials in good condition are safe unless asbestos fibres become airborne, which happens when materials are damaged.
Some of the more common uses of asbestos in buildings include:
Sprayed coating: asbestos is found as fire protection on structural supports like columns and beams. It is a high hazard asbestos product and can generate very high fibre levels if disturbed.
Pipe Insulation: asbestos thermal pipe lagging is a high hazard asbestos product.
Asbestos insulating board (also referred to as AIB) ceiling and door panels: AIB is a high hazard asbestos product and can generate high levels of fibres if the board is cut or drilled.
AIB window panel: like other AIB, this is a high hazard asbestos product, and if in good condition should be left undisturbed.
Floor tiles: vinyl (PVC) or thermoplastic tiles contain asbestos.
Asbestos cement roof sheeting: asbestos cement sheeting is often found on industrial building roofs and walls.
Textured decorative coating (such as Artex): textured coatings contain a small amount of asbestos. The asbestos is well bonded and fibres are not easily released. However, it is still an asbestos product, and as such, needs to be worked with safely.
Types of asbestos
The three most common forms of asbestos used in the UK were:
Chrysotile (white asbestos)
Amosite (brown asbestos)
Crocidolite (blue asbestos)
White asbestos was mined mainly in Quebec, South Africa and Central Russia. This contains the softest asbestos fibres which under a microscope will appear curly and flexible. The individual fibres are less carcinogenic than blue or brown asbestos fibres.
Blue & Brown Asbestos
Blue asbestos and brown asbestos were mined mainly in South Africa. The fibres appear very sharp, stiff and needle-like. Blue asbestos is the most carcinogenic and was often used for insulating naval vessels. Due to its excellent resistant properties to acids, it was mixed with cement to produce asbestos cement sheets that were designed to be exposed to chemicals.
A further form of asbestos is known as Tremolite, which can be found in the earth’s crust, but has only been mined commercially on a small scale. Traces can be found in some industrial talc.
Asbestos was used as an insulation material from the early part of the 19th Century because of its heat resistant properties. It could be fashioned into a paste, into sheets or rope. The real increase in the use of asbestos in the UK occurred after the 1930s. It was used for corrugated roofing, insulation around pipe work, in sheet form to box in pipes, on ships, in houses, in factories, in power stations, and in public buildings such as schools and hospitals. It was mixed and cut. In addition, asbestos was often stripped from pipes and boiler work to maintain valves and pipes underneath.