More than 5,000 workers in the UK die every year of asbestos-related diseases according to figures gathered by the Health and Safety Executive (HSE). It is still commonly found in many buildings and products built before the year 2000.
The deadly nature of asbestos and its abundance in older buildings and structures means it is one of the most hazardous materials that can be found in the workplace.
However, despite the associated hazards, many people still do not have a good understanding of the different types. So, what is asbestos, exactly? In this article, we will look at the 3 main types of asbestos and their properties; when and what they were used for and when their usage in the UK became prohibited by law.
What is Asbestos?
Asbestos is a naturally occurring silicate mineral found in the ground. It is composed of fibrous materials that have crystallised into fibres. Once frequently used in a variety of products from insulation to car parts to floor tiles, certain types of asbestos are now prohibited for sale or use in the UK due to the significant health risks that they pose.
It has many useful properties that, in the past, made it useful in many applications, for instance:
- It is strong and flexible
- It doesn’t burn
- It doesn’t conduct heat or electricity
- It has good resistance to chemicals
It is commonly mined in:
- South Africa
The various types of asbestos belong to either the serpentine class or the amphibole class. These two classes have different physical characteristics. Serpentine has fibres that are curly. Amphibole fibres are straight and look like small needles.
The majority of its types fall under the umbrella of amphibole. There are six different types that can be identified by how they look, although this requires close examination under a microscope.
The 3 main types of asbestos that were commonly used are:
- Chrysotile or white
- Crocidolite or blue
- Grunerite or brown
It’s important to realise that, while the common types of asbestos are referred to as brown, blue or white, any materials containing them are unlikely to look brown, blue or white.
White Asbestos - Chrysotile
Chrysotile, also known as white asbestos, falls under the umbrella of the serpentine class. It was the most common type and can be found in 95% of all asbestos-containing materials (ACMs).
White asbestos fibres have high flexibility, are heat resistant and resistant to alkalis. Due to their greater flexibility, the fibres can be spun or woven into fabric.
Chrysotile was used in a variety of products, such as:
- A reinforcing agent in products like cement
- Corrugated asbestos cement roof sheets on buildings
- Joint compound
- Brake linings
- Fire barriers in fuse-boxes
- Floor tiles
- Pipe insulation
It was banned for use or sale in the UK in 1999 as part of the Asbestos (Prohibitions) (Amendment) Regulations 1999.
Blue Asbestos – Crocidolite
Crocidolite fibres look like needles and are very strong. The mineral is commonly found in South Africa, Australia and Bolivia. Blue asbestos, like brown, is hydrophobic, so it repels water. The fibres also have a high resistance to acids.
It was often used in yarns, and for insulation boards and lagging. It was also sprayed onto surfaces as insulation.
It is the most dangerous and was banned throughout the UK in 1985 under the Asbestos (Prohibitions) Regulations 1985.
Brown Asbestos – Grunerite
In its natural state, amosite, or brown asbestos, is known as the mineral grunerite. Amosite is named from the acronym for ‘Asbestos Mines of South Africa’, which is where the mineral is commonly mined. When viewed under a microscope, amosite fibres are spiky, harsh and grey-white in colour
As with blue, brown asbestos is hydrophobic. As a result, dampening down with water is not an effective way of controlling brown asbestos fibre release.
It is very strong and is good at resisting acid and heat. It was widely used as:
- Fireproofing on steel structures
- Thermal insulation
- Soundproofing material
- Anti-condensation material
It was also banned for use in the UK in 1985 under the Asbestos (Prohibitions) Regulations 1985.
Tremolite, Anthophyllite and Actinolite
There are three types of asbestos that were not commonly used but can still be found in some insulation materials or as contaminants. These are:
These were banned in the UK under the Asbestos (Prohibitions) (Amendment) Regulations 1999.
All can be extremely hazardous and pose a significant risk to human health.
The Hazards of Asbestos
When it is in large forms and not damaged, it is not considered to be harmful. However, damaged asbestos can result in the release of asbestos fibres that, when inhaled, can cause serious, life-threatening diseases.
Breathing it in can cause:
- Mesothelioma (a form of cancer)
- Asbestos-related lung cancer
- Asbestosis (scarring of the lungs)
- Pleural thickening
Related illnesses can go undiagnosed for years. When it is finally diagnosed, it is usually too late for treatment and the patient’s condition is considered to be fatal. It can take up to 50 years, after the initial exposure, for asbestos-related cancer to appear. Click here for a free Asbestos Health Hazards Infographic, that can be shared.
Further Training on Asbestos Safety
Asbestos is a highly hazardous material still found in many older buildings and products throughout the UK. Anyone that works in an environment where they might come into contact with it must be fully informed about the health risks, reminded about the risks (click here for a free poster)and know what safety measures to take. Training can help people to fully understand what is asbestos and the risks surrounding it. Human Focus provides a range of accredited online asbestos courses that give trainees the skills and knowledge they need to stay safe in the workplace.