What exactly is asbestos and why was it used?
Most of us have heard of asbestos and know that it is a dangerous material but where does it actually come from and why was it used so extensively as a building material? This page will outline the historical use of asbestos and explain where it is most likely to be encountered.
Asbestos is a set of naturally occurring silicate minerals that can be extracted from three types of rocks: serpentinites, altered ultramafic rocks and some mafic rocks. The common feature to all of these minerals is their thin, fibrous crystals. Once extracted, these fibres have remarkable properties that make them incredibly useful and ultimately led to such widespread mining of asbestos by numerous civilisations throughout history. In addition to being a cheap and plentiful material, asbestos also has excellent resistance to chemical, water and fire damage. Being a good thermal and electrical insulator also helped asbestos to become one of the primary building materials in the twentieth century where it was added to a wide variety of products. During this time an estimated 6 million tons were imported into the UK. Despite being hailed as a 'wonder material' asbestos was noted to be hazardous to health as far back as 1899 by Dr. Montague Murray. The first documented death due to asbestos exposure was later recorded in 1906 and the first diagnosis of 'asbestosis' made in 1924.
China is the World's biggest producer of asbestos with Canada in second place.
The benefits of asbestos were discovered as long ago as 4500BC when anthophyllite was being used in Finnish pottery as a strengthening agent within the clay, increasing the durability of pots and other containers. Around 4000BC, it's ability to resist heat was known and utilised to create long-lasting wicks for lamps and candles. It was also later used by the Egyptians in 2000-3000BC to wrap embalmed pharaohs, protecting their body from decay within the tomb.
However, it wasn't until the late-nineteenth century that the large scale asbestos industry exploded with large mines being exploited in both Canada and South Africa. England, Scotland and Germany soon developed yarn manufacturing processes to take advantage of the resource. After the Second World War, asbestos was relied upon heavily in the building industry as construction boomed and it was in the early 1970's that asbestos use reached its peak. It's prevalence created a huge variety of contaminated building materials, with fibres frequently being added to mixtures such as cement. Due to growing concerns over the dangers of asbestos to workers' health, the importation of crocidolite fibres in the UK ceased in 1970 and amosite in 1980. Shortly after, the Asbestos (Prohibitions) Regulations 1985 banned the import, supply and use of crocidolite and amosite as of January 1, 1986. These regulations were amended in 1999 to incorporate white asbestos (chrysotile) creating a total ban on all asbestos use and importation within the UK. It is disappointing to note that asbestos is still mined and used elsewhere around the world despite the dangers and clear evidence of mortality through exposure.
Estimates suggest that up to 50% of private homes may include asbestos containing materials (acm's) in their construction. As a potentially lethal substance this highlights the seriousness of increasing public awareness... and particularly the need to train tradesmen and those regularly working on residential property. David Young, Kovia Ltd Director
WARNING: Asbestos can be found in hundreds of products that you may not be aware of.
For a comprehensive but not exhaustive list of asbestos products please visit the HSE website.
- Rope Seals
- Pipe Lagging
- Insulation Board
- Cement Roof Tiles
- Corrugated Roof Sheets
- Vinyl Floor Tiles
- Bitumen Adhesive
- Roof Felt
- ...and many more