What harm does asbestos do?

Asbestos poses health risks only when fibres are present in the air that people breathe.

How exposure to asbestos can affect you depends on:

• the concentration of asbestos fibres in the air
• how long the exposure lasted
• how often you were exposed
• the size and type of the asbestos fibres inhaled
• the amount of time since the initial exposure.

When inhaled in significant quantities, asbestos fibres can cause asbestosis (a scarring of the lungs which makes breathing difficult), mesothelioma (a rare cancer of the lining of the chest or abdominal cavity) and lung cancer. The link between exposure to asbestos and other types of cancers is less clear.

Smoking, combined with inhaled asbestos, greatly increases the risk of lung cancer.

What is asbestos?

Asbestos is the generic name for six naturally occurring minerals that have been used in commercial products for their strength, flexibility, low electrical conductivity, and resistance to heat and chemicals. It is composed of silicon, oxygen, hydrogen, and various metals.  Asbestos is found naturally in rock formations around the world. Because of their charcateristics asbestos fibres were widely used by industry, mainly in construction and friction materials. The six types of asbestos belong in two broad mineralogical groups: serpentine (chrysotile) and amphibole (amosite, crocidolite, and the less prevalent tremolite, actinolite and anthophyllite).  The three more prevalent forms have the common names; white = chrysotile, blue = crocidolite & brown = amosite.

• Chrysotile is the only serpentine asbestos.  It can be found in almost all asbestos-based products.and is the main form of asbestos still mined. Chrysotile is different from the amphiboles both structurally and chemically. The fibres are longer and flexible.  It is generally accepted that chrysotile asbestos is less potent and does less damage to the lungs than the amphiboles.  It is a magnesium silicate.
• Amphibole asbestos often contains more iron and resists acid and extremely high temperatures. Because of this, it has been heavily used in industrial furnaces and heating systems. However when inhaled, amphibole fibres stay much longer in the lungs than chrysotile fibres and they are more likely to inflict damage and cause disease, including cancer. Amphibole fibres are shorter and less flexible.  Accordingly, amphibole asbestos has been drastically controlled and largely replaced.  Amosite contains iron and magnesium.  Crocidolite is sodium iron magnesium silicate.  Anthophyllite ranges in colour from white to gray to brown. It is associated with talc and other minerals, and is a magnesium iron silicate hydroxide.  Tremolite is a calcium, magnesium, iron silicate, which is white to grayish green and can be found in metamorphic rocks. Actinolite has a chemical formula that is similar to tremolite, but actinolite contains more iron in relation to magnesium than does tremolite. It appears as dark green crystals or fibrous aggregates.

How much asbestos is in a product does not indicate its health risk. If the asbestos fibres are enclosed or tightly bound in a compound, there is no significant health risk. One of the main problems with asbestos came from sprayed or "friable" (easily broken up) amphibole asbestos used in buildings. People working in construction, maintenance or in the renovation of older buildings should be particularly careful when handling this asbestos.

Over 90% of all asbestos ever used was the white asbestos. Blue and brown asbestos where the other two forms used in buildings.  Uses of white asbestos include brake linings, gaskets and seals, asbestos cement and composite materials like textiles (eg asbestos gloves).  Blue and brown asbestos was used in sprayed coatings, thermal insulation and insulation board etc.  Blue and brown asbestos was sometimes mixed.  Trace elements of the less common forms can sometimes be found as contaminants with the more common forms.

The use of all three commercially used forms of asbestos has now been banned in the UK with the UK ban on the use, supply and importation of white asbestos coming into effect from 24/11/99. The use of blue and brown asbestos has been banned in the UK since the mid 1980s.

As the timings of these bans suggest, even though all the forms of asbestos are carcinogens (cause cancer), it is the blue and brown forms that are more dangerous.

Currently, chrysotile is the only type of asbestos mined on a large scale. Small amounts of tremolite asbestos are still mined in India.

Who is responsible for asbestos in a building?

The Control of Asbestos Regulations 2006 places a responsibility and duty on "every person who has, by virtue of a contract or tenancy, an obligation of any extent in relation to the maintenance or repair of non-domestic premises....".  Such person is referred to as the "duty holder" within the legislation.

This generally means building owner (free holder) or tenant if leased on a full repairing lease.  However the landlord may still be liable for common parts serving more than one tenancy.  If properties are sub-let it is important for each tenant to understand his obligations under his tenancy.

Whilst the building owner may delegate the responsibility for day to day management of the asbestos in the building to a facilities management company or the like, it is not normally possible to delegate duty under statute.  It is possible that the building owner could be vicariously liable for any act of failure or omission on the part of the facilities management company.  This is more likely if the building owner could not demonstrate that he had carefully vetted the facilities management company initially and had confirmed that they had a robust quality assurance system.

The duty to manage asbestos in premises does apply to common parts of housing developments and blocks of flats.  This duty does not extend to the individual housing units but these are subject to the Defective Premises Act 1972, which places a duty on the landlord to take reasonable care to ensure that tenants and others are safe from disease caused by a defect in the premises.

What is an Asbestos Register?

This is the document that would be prepared by an asbestos surveyor following an asbestos survey.  The asbestos register should be kept on site to inform any workmen that are required to do work to the premises.  The asbestos register should include the location and detail of all asbestos containing material (ACM) in the premises.  It should also include a material risk assessment and a priority risk assessment with recommendations.  The asbestos register should be kept up to date and be readily available.

PHH Environmental can provide password protected internet access for clients to their asbestos registers.  This allows remote sites or approved contractors to have 24 hour access to the site's asbestos register.  This can be extremely useful for maintenance contractors to allow access to the information before visiting site or when working on remote sites that may not have the capacity to hold 'hard copy' of the asbestos register.  The asbestos register would be available in Adobe Acrobat pdf format allowing the password protected document to be viewed on any computer.