Asbestos Materials

A surprising number of products and materials contain asbestos fibres. Asbestos is a naturally occurring mineral that was popularly used between the 30's and 80's because of its strengthening and resistance properties. Asbestos was initially used as a thermal insulation product because of its resistance to high temperature. It was also used in plastics and cements as a binding agent .

In the 60's it was discovered that asbestos containing materials were dangerous because when the products are damaged and the fibres are released into the air they can ve inhaled and lodged in the linings of the lungs causing ilness and disease (see Asbestos Illness). A single fibre can cause cancer but, as with smoking, the more you expose yourself the higher the likelihood of developing a problem.

If an asbestos containing material (ACM) cannot release fibres it is of no risk. Therefore, the most significant factor when calculating risk is the likelihood of fibre release following disturbance - known as friability. Low-risk ACMs are normally considered so because they are normally of a solid or pliable(composite) nature and do snap or break and thus do not shed fibres in large numbers even when badly damaged. However, high-risk materials are normally brittle or very friable and will often fill a room with airborne fibres when disturbed.

There are six different asbestos types and each has its own associated risk level.. Three of these are commonly found in ACMs; Chrysotile (known as white asbestos), Amosite (brown asbestos) and Crocidolite (blue asbestos) . These are split into two groups; Amphibole and Serpentine. The most dangerous group of asbestos types - Amphibole asbestos - includes Crocidolite, Amosite and the less common Anthophyllite, Tremolite and Actinolite. The use of all Amphibole asbestos was banned in 1985 and all are most commonly found in thermal insulation products. The least dangerous is group - Serpentine asbestos - is formed only of Chrysotile which was commonly used as a binding agent and was used in almost all material types (especially asbestos cement) until it too was banned in 1999.

The following is a breakdown of the most common Asbestos Containing Materials;

Building materials

Cement

In asbestos cement products asbestos fibres are added to cement to form a very strong and resilient building material. Asbestos cement is also particularly useful because it can be moulded and thus used to create a range of products that include rainwater goods and profile roofing sheets.

Asbestos cement usually contains the lower risk Chrysotile (white) asbestos fibres. That said it is often worth having a sample analysed to determine whether the higher risk Amosite (brown) or Crocidolite (blue) asbestos fibres are present.

Asbesto cement is hard to break or damage and will therefore rarely release any dangerous fibres unless sanded or broken and is generally regarded as a low risk material and can be removed by non-licensed contractors. If you intend to remove asbestos cement yourself  you should take adequate care to protect yourself by wearing disposable coveralls and suitable face masks (we recommend P3).

ASBESTOS CEMENT ROOFING SHEETS
Perhaps the best known asbestos containing material; asbestos cement roofing sheeting can commonly be seen on shed and warehouse roofs in every town in the UK. The presence of asbestos is often indicated by mosses which grow on this natural mineral.

ASBESTOS CEMENT GUTTER AND ASBESTOS CEMENT PIPES
Asbestos cement rainwater products (which include asbestos guttering and asbestos drainage pipes) were used extensively up until the 1990's. Asbestos cement is resistant to most acids and alkalis making it perfect for transporting rain water from your roof to your storm drain. Other asbestos cement goods also include asbestos water tanks,  asbestos conduits, asbestos window boxes and asbestos sewer pipes.

Asbestos flue pipes are also common because of its additional thermal resistance properties.

ASBESTOS CEMENT BOARD
Asbestos cement board was commonly used in properties built in the 50's and 60's when it was commonly used for panelling in studded partitions, ceilings, soffits and bathrooms.

ASBESTOS FLASHGUARDS
A very common use of asbestos cement is as a flashguard, linings to electrical goods that protect the object from sparks and electrical current. These are very common in electrical switchgear, fuseboxes, fuses and transformers. As with all cement products the risk of fibre release is low unless the product is damaged.

ASBESTOS ROOF TILES
Asbestos roof tiles ( occasionally referred to as shingles) are still common on British rooves. Because asbestos is a naturally occurring mineral you will often see moss and algae growing on these tiles as opposed to non-asbestos rooves where only a few tiles will be moss-covered.

Asbestos Roof Felt

Asbestos roof felt was used between 1910 and 1995 and typically contains 10-15% Chrysotile (white) asbestos fibres mixed with asphalt. It is a composite asbestos containing material and therefore there is little risk of fibre release unless badly damaged.

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Thermal Insulation

Products used for thermal insulation (rather than protection) generally pose the biggest risk. This is because they tend to contain high percentages of asbestos which are normally Amosite (brown) or Crocidolite (blue) that are generally considered to be more dangerous than Chrysotile (white).

Contractors require an HSE licence to remove or work upon any of these products. These works will always be carried out in controlled conditions typically involving respiratory protective equpment, purpose-built enclosures and decontamination procedures.

ASBESTOS INSULATION BOARD (AIB)
Asbestos Insulation Board, or AIB, is the most common of the asbestos insulation productsasbestos insulation board still in situ (many of the others have been removed). It was typically used to clad areas around heat sources such as boilers and hotwater pipes.

AIB is very similar to plasterboard (especially Superlux) in consistency and was commonly used from 1930 up until 1985 when it was banned (along with all other asbestos products that contained Amosite or Crocidolite). AIB normally contains upto 30% of Amosite (Brown asbestos) and/or Crocidolite (blue asbestos) meaning it poses a high risk when the fibres are exposed or the product is damaged.

AIB is also commonly used as a fireproofing material particularly in ceilings (often in the form of ceiling tiles), partition walls and firebreaks. Unfortunately it was also used as a building material and was often used for soffits and cladding (in fact anywhere you might use plasterboard you will find AIB).

ASBESTOS SPRAYED COATING
Asbestos sprayed coating, or flock, was an asbestos compound (often pure asbestos) sprayed directly onto surfaces to form a hard asbestos sprayed coating layer for the purpose of fireproofing, thermal insulation, sound proofing and even decoration. Over time asbestos sprayed coating decomposes and become unstable. This increases the risk of fibres being released often through minimal contact and thus it can be extremely hazardous especially as it can have concentrations of upto 90% asbestos.

It is very difficult to work with this material without significant fibre release so you should always consult an HSE licensed contractor before commencing remedial works.

ASBESTOS LAGGING AND PIPE WRAP
As with asbestos sprayed coating, asbestos lagging has very high concentrations of amphibole asbestos (brown or blue) and releases fibres after minimal contact or disruption. Often, though, asbestos lagging will be covered in a protective material or sealant (paint) that protects it, with the aim of preventing fibre release. If the protective layer remains undamaged the material will be safe but, often this is not the case and the product needs to be repaired or re-sealed.

Asbestos lagging is difficult to remove because it tends to adhere to the surface of the item that is lagged. Removal should only be attempted by licensed contractors and it is often cheaper and safer to repair or protect asbestos lagging. 

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Fireproofing using asbestos

Asbestos containing materials were used for fireproofing from the mid 1920s through to the 90s. 

ASBESTOS PAPER AND ASBESTOS MILLBOARD 
Asbestos mill board which is similar to cardboard and asestos paper was often used as a fire protective lining to ovens, PVC tiles, pipe insulation, plant, heaters, damp course, cladding and inside metal fire-doors where it acted as a soundproof fireproofing agent. It was also commonly used in library and  bank vaults as a fireproof lining for boxes.

ASBESTOS TEXTILES 
Asbestos' fibrous nature makes it particularly suitable for weaving into asbestos textile textiles such as rope, cord and  cloth. These textiles were particularly useful becase they were fireproof and were often used to make products such as ironing board covers, fire blankets, oven and window seals and coiled around handles on kitchenware such as kettles and pots to prevent burnt fingers.

Asbestos textile was also used as a cable-wrap and to form asbestos curtains(especially in theatres), asbestos matresses and asbestos packing.

 

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Plastics

Plastic is formed of a polymer combined with a fibrous binding agent to produce a material that is strong and composite but also maleable. Asbestos was an ideal binding agent because it was very strong and hard wearing.. These materials form the lowest risk of all asbestos containing materials because polymers do not decompose and the asbestos fibres remain protected for many years. 

ASBESTOS FLOOR TILES
From the 50's until the 80's asbestos fibres (Chrysotile) were used in polyvinyl plastics often used as floor tiles and stair nosings.  The bitumen adhesive used to affix these tiles often contains asbestos fibres too. This is a low risk product when left in-situ but care should be taken when removing asbestos floor tiles. We'd recomend sing a specialist contractor but in any case a mask should be worn toprotect the lungs. 

ASBESTOS TOILET CISTERNS
To this day solid black or brown plastic toilet cisterns are commonly found in public conveniences, pubs and civil buildings. These asbestos toilet cisterns often contain Amosite (brown asbestos) or Chrysotile (white asbestos) fibres. The risk of fibre release is very low because of the strength of the material but you should avoid breakage.  

ASBESTOS BITUMEN SINK PADS
Asbstos bitumen sink pads are often found under older metal sinks where they were used to reduce the noise produced by running water. They often contain Chrysotile fibres but form a very low risk because they are of a composite nature and do not release fibres unless disturbed. In most instances it is safer toleave the product where it is or dispose of the whole unit as scraping will release fibres.

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Friction Products

Asbestos fibres are very strong and heat resistant are, therefore, well-suited to use as a friction resistant product such as a brake or gasket.

ASBESTOS BRAKE LININGS
Up until the 80s most brake linings contained asbestos but an asbestos ban in asbestos brake lining Scandanavia less hazardous alternatives.were found and used. Some older vehicles and motors (particularly lift motors) still contain asbestos brakes.

Obviously asbestos brake linings do wear and fibre-release is inevitable so the dust around the product wil be high risk and should be treated with caution. 

In effected areas (such as lift motor rooms) an air test can be performed to identify if levels of airborne asbestos fibres exceed the legal working maximum.

ASBESTOS GASKET
Asbestos was the ideal material for uses as a gasket because of its extraordinary resistance to chemicals, electricity, heat and wear. It was particularly common at heating pipe joins. Generally asbestos gaskets were formed from Chrysotile.

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Adhesives and sealants

ASBESTOS RESINS, MASTICS, PUTTY & TILE ADHESIVES
Chrysotile (white) asbestos was commonly used as a binding agent in resin, mastic, putty and flooring adhesives from the 40s through to the 80s. These are in the lowest risk category of asbestos containing materials because the product is composite and asbestos fibre release is unlikely. As with al asbestos products, care should be taken not to sand or scrape these products.

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Decorative

ASBESTOS PAINT & TEXTURED COATING (ARTEX)
Small amounts of Chrysotile asbestos are sometimes found in textured coating (also known as Artex) and some decorative paints that were manufactured before te end of the 70s. These products are low risk when left but because of their nature they are often drilled or sanded. These actions can result in fibre release and as a precaution we recommend damping down of the area before commencing work.

Up until 2006 the removal of artex was licensed but this is nolonger the case. We would reccomend however that you use an experienced contractor to remove the material. As a minimum precaution you should wear a mask when removing Artex.

Products are now available in your local DIY store that allow you to skim or plaster over Artex.

ASBESTOS WALLPAPER
Older vinyl wallpaper that pre-dates 1980 can contain small quantities of Chrysotile (white) asbestos. This is little risk of fibre-release from such products is unlikely unless damaged and you should avoid scraping or removal without wearing a mask.

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