Once embraced as the ‘miracle mineral’ for its tough, flexible, fireproof qualities, asbestos is now seen as a killer. The International Labour Organization (ILO) estimates that 255,000 workers die each year worldwide from asbestos-related diseases.

Even in Europe, where asbestos use is banned, asbestos-related disease is still the leading cause of occupational death. This is because many workers, especially tradespeople such as plumbers, builders, electricians, etc., are frequently exposed to airborne asbestos fibres that are produced when the materials containing them (such as insulation, ceiling panels, floor tiles and textured wall coverings, etc.) are disturbed. There are millions of tonnes of asbestos products in existing buildings across the EU, and in the UK alone, any building built before the year 2000 can contain asbestos.

Traditional methods of airborne asbestos detection involve collecting particles from the suspect environment and then using microscopy or x-ray analysis to look for fibres. This process could take days, by which time inadvertent inhalation of asbestos could have been suffered by anyone entering the tested environment. Until now, there has been no quicker way of detecting the presence of airborne asbestos fibres. However, the Asbestos Alert is a new technique which can analyse airborne particulates in real-time and determine whether or not fibres are present and whether those fibres are asbestos.

The ‘ALERT’ real-time warning asbestos detection device can detect airborne fibres in minutes or even seconds (depending on fibre concentration) rather than days . It has been tested extensively in field locations involving commercial, public, and domestic buildings where asbestos clearance work (so far involving crocidolite, amosite and chrysotile asbestos forms) has been undertaken.

Currently, the most common way to identify hazardous airborne asbestos at worksites is to filter the air, count the number of fibres that are caught, and later analyse the fibres with X-ray technology to determine if they are asbestos.

This approach requires expensive lab work and hours of wait time.

An alternative method to evaluate work site safety is to use a real-time fibre detector, but the current, commercially available detectors are unable to distinguish between asbestos and other less dangerous fibers such as mineral wool, gypsum and glass.

ALERT’s patented design analyses the airborne environment in real-time utilising both laser-light scattering technology, the paramagnetic properties of asbestos* and a unique algorithm to make a statistical analysis of the asbestos detection samples in real-time to 99% confidence.

Air is drawn in a controlled manner through the ALERT inlet at ~50ml/ min, at up to 600 particles per second through a pair of laser beams and a magnetic field.

When a particle is illuminated with a beam of light in ALERT’s optical chamber, it will scatter the light in a pattern dependent on its size, shape, and structure. These patterns are like a thumbprint and are recorded and used to ascertain whether the particle is fibrous or not.

Asbestos fibres produce distinctive scattering patterns as can be seen in the examples below. However, the light scattering technique alone is not enough to differentiate between highly dangerous asbestos fibres and far less hazardous but generally more common fibres of, for example, glass or gypsum also commonly found in built environments.

Example of forward scattering patterns.  Top row: Background particles; Middle Row: Crocidolite fibres; Bottom Row: Chrysotile fibres

All fibrous particles are preferentially aligned vertically by ALERT’s airflow and the system will measure the angle of alignment as it enters and then transits between the two laser beams.
The paramagnetic properties of all asbestos fibres mean that when exposed to a magnetic field asbestos fibres will try to align themselves. This change in alignment is measured by ALERT’s algorithm enabling a distinction of asbestos fibres from other non-asbestos fibres passing through the optical chamber.

The schematic below illustrates ALERT’s dual-beam asbestos warning system and the forward scattered light which is focused and recorded twice—once before and once after exposure to a magnetic field.

*Certain types of man-made fibre such as steel or magnetically engineered fibres may have similar magnetic properties to those of asbestos and could therefore be wrongly assessed by the asbestos detection device. However, unlike asbestos such fibres are not normally found in the ambient airborne environment where building, renovation or demolition work is being undertaken.

(Source: Images on this page are courtesy of the University of Hertfordshire)

Alert Technology Ltd, a spin off The Select Group of Companies (the ALERT FP7 project’s Exploitation Managers) are responsible for production and commercialization of the Asbestos ALERT.

A limited number of pre-production sample units are being developed in readiness for robust field trials in a variety of industry sectors. For updates on future launch dates please sign up for our newsletter or contact Alert

Prices for the Asbestos ALERT range have not yet been fixed but there are plans to launch the Asbestos ALERT Pro model first aimed at professionals who require downloadable information.

The price of the future smaller ‘Tradesman’s Model’ has not yet been released but it is Alert Technology’s aim to make the device affordable in line with other electronic instruments used regularly by the trade, with the hope that as production increases after the initial product launch, that costs may be reduced further making the asbestos detectors even more affordable for an individual plumber, electrician or building renovator.

“These tradespeople are the most frequently affected by asbestos-related diseases and most who get the diseases will die from them,” the team says.

The company have also identified a number of industry specific models for future development along with a Fixed Perimeter Model that works to clearance levels.