by Dr Saeed Doroudiani

The construction industry is one of the fastest growing sectors in the world, particularly in larger countries such as China and India. The living quality and expectations of residents are changing, which bring great demands to high-quality building materials and technology.

Fibre reinforced plastic composites (FRP) provide useful properties and performance in a wide range of applications in building, aerospace, marine and automotive industries because of their good mechanical properties over conventional materials. The applications of FRPs in buildings are significantly increasing. They are used more often in buildings and in making furniture and some other items, such as bathroom cabins and storage room shelves.

Despite many advantages, FRPs are easily flammable. Glass, carbon, aramid and cellulose fibres are the most regular reinforcing fibres used in FRP. When exposed to fire, the plastic component of the composite burns and the fine fibres with diameters in the range of micrometres or nanometres are released to the atmosphere. These fibres create similar threats to human health as asbestos.

The potential health risk of carbon fibre-based FRP to produce dangerous inhalable fibres has been investigated and was found that the health risk is related to the surface temperature, the oxygen level and the airflow field close to the material surface. In addition to fine fibres, burning of FRP produces large amounts of carbon dioxide, carbon monoxide, soot and various kinds of chemical compounds with similar structures as monomers of the polymeric matrix.

The composition of the burning products mainly depends on the environmental conditions and availability of air (oxygen). For instance, in the shortage of air conditions, less carbon dioxide and more toxic carbon monoxide, organic compounds and soot are produced.

The safety issues related to building materials and their toxicity, including FRP, have recently been reviewed in a book with a title of Toxicity of Building Materials.

Dr Saeed Doroudiani, Senior Scientist/Consultant, Canada