Asbestos cement

Asbestos cement (AC), also known as ‘fibro’ or AC sheet, is a thin cement sheet or panel which is given rigidity by the inclusion of asbestos fibres. Asbestos cement can be moulded into any shape that ordinary wet cement can, but typically, it is formed into flat or corrugated sheets or piping. AC is generally grey or brown in appearance and has a coarse texture.

AC became popular during and post-World War II as a means of building inexpensive structures. It was also promoted as a fire-resistant alternative to more common roofing materials such as asphalt as well as an affordable alternative to timber shingles, brick, slate and stone. Today, AC is commonly found in the roofs and walls of old sheds, garages or in soffits beneath eaves.

The use of AC has been banned in several countries. This is because it contains asbestos and when it ages it releases tiny fibres into the air which can be inhaled in the lungs and may increase the risk of lung diseases.

Contractors for licensable asbestos removal are held on a list by the Health and Safety Executive (HSE). However, AC panels are a non-licensable asbestos product, which means they may be removed by non-licence holders but the work must be carried out in accordance with HSE requirements by suitably-trained personnel.

The removal of AC panels is an exception, as the asbestos is in a bound matrix that is generally capable of remaining rigid without releasing fibres into the air. Panels may be discoloured or cracked in places but this will not negatively affect their integrity and make them hazardous. AC panels can be found indoors, but as long as they are undamaged they do not need to be removed, but should be subject to regular checking, and can be sealed with paint or sealant.

In the UK, there is no legal requirement to dispose of AC, but care should be taken not to damage the panels in a way that could generate dust, thereby releasing fibres. If homeowners require it, they can arrange the disposal of AC panels with the help of the local council.

Safe steps to take when removing AC sheets include:

• Using a water sprayer to dampen the area around bolts and fasteners and reduce dust.
• Avoiding the application of pressure to panels which could cause them to break.
• Avoiding cutting, breaking or doing anything to panels which could generate dust.
• Lowering the panels carefully and placing them in strong polythene sacks sealed with tape.
• Clearly labelled the sacks as containing AC.
• Removing any debris.
• Cleaning equipment, surfaces and protective clothing that may have dust on them.

The Control of Asbestos Regulations 2012 suggests that “asbestos cement” means a material which is predominantly a mixture of cement and chrysotile and which when in a dry state absorbs less than 30% water by weight.

[edit] Related articles on Designing Buildings Wiki

• Asbestos in construction.
• Asbestos management.
• Asbestos register.
• Cement.
• Construction dust.
• Deleterious materials.
• Failure to mention asbestos.
• Fibre cement.
• Five signs you are at risk of asbestos poisoning at work.
• The risk of asbestos on brownfield sites.
• Types of cement.