for the development of asbestosis and related diseases. Taking into account evidence presented by economists and building industry management, however, the report assumed that, despite the availability of other materials, asbestos would continue to play a major role in the British building industry for many years to come because of its versatility and cost effectiveness.
As a result, the council issued a series of recommendations which were intended to reduce the risks to those who might be exposed to asbestos in working environments. They recommended that, where possible, asbestos-free materials should be employed. In cases where asbestos was employed, it was recommended that it should be used in a bonded form with materials such as cement, so that loose fibers were less likely to enter the air. The report recommended that special care should be taken during work in environments which contain asbestos. Workers should wear protective respiratory equipment and take special care to remove dust from the environment and clothing with the use of vacuum cleaners.
The report isolated five factors which determine the level of risk involved. The state and type of asbestos is critical to determining the risk factor. In addition to the use of bonded forms of asbestos in preference to loose forms, dust formation was found to be limited where the asbestos was worked when wet rather than dry.
The choice of tools was also found to affect the quantities of asbestos particles that enter the air. Machine tools produce greater quantities of dust than hand tools and, where possible, the use of the latter was recommended.
A critical factor in risk reduction is the adequate ventilation of the working environment. Where work takes place in an enclosed space, more asbestos particles circulate and it was therefore recommended that natural or machine ventilation should be used. By rigorously following these guidelines, it was claimed that exposure can be reduced to a reasonably practicable minimum.
The report stated that research carried out by the NMRC showed that the maximum safe level of exposure to blue asbestos was 0.1 fibers per milliliter in an eight-hour working day, whereas as much as 1.0 fibers per milliliter of amosite and chrysotile (white asbestos) could be inhales. If these levels are str5ictly adhered to, the report claimed that the onset of asbestosis in a normal working life should not develop.
Critics of the report pointed that insufficient longitudinal studies had been carried out to determine that the reports recommended maximum safety levels were acceptable.
If, as some as yet unconfirmed data suggest, even minimal exposure to asbestos may result in disease, then clearly the report should have stated that the employment of asbestos was unacceptable in any form.

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