We manufacture an instrument called Fibrecheck™ which is used to examine ambient air for the presence of asbestos fibres. Usually it is used in places where asbestos is suspected of being present, for instance when it is being stripped out of a building, or where asbestos in a fragile state is known to exist. Factories that process asbestos or other fibrous materials also use it for routine air monitoring. It is small, self-powered, simple to operate, and easily portable.
Fibrecheck™ works by pumping a sample of air (at a rate of 2 litres/minute) through a laser illuminated chamber. Laser light, scattered by microscopic particles in the air, is collected by an array of special photo-detectors, and then analysed by means of a micro-processor, to identify each particle's "signature". Fibrous particles are recognised by their laser scatter "signature", and counted.
In operation the FibrecheckTM instrument can be set to sample air for between one minute, and eight hours. During this time the fibres are counted and, from a knowledge of the air flow rate, the concentration of fibres can be determined. The display of fibre concentration is shown on an LCD and is updated every minute
In the U.K. it is generally considered safe for the public to be admitted to an area where the fibre count is less than 10 fibres per litre of air. Fibrecheck™ can measure this concentration with an equivalent accuracy to the conventional laboratory methods in about fifteen minutes.
The traditional methods for measuring fibre concentration involve complicated laboratory techniques which are time consuming and only reveal a dangerous fibre level a long time after the event.
Apart from its readout of fibre concentration Fibrecheck™ emits a "bleep" every time a fibre is detected. This allows it to be used in an analogous way to a geiger counter. Most importantly, it gives an instant warning of the presence of potentially dangerous fibre levels in the air.
Because all particles passing through the laser chamber are investigated, and counted, Fibrecheck™ also gives a secondary readout showing the total dust levels present. This can be of use in those industries where low concentrations of toxic dusts are present, and need to be measured.