Description

Concern about the development of disabling pneumoconiosis

led to the setting up in the early 1950s of the Pneumoconiosis

Field Research, a long-term project supported by the National

Coal Board, the stated purpose of which was “to establish

what environmental conditions should be maintained if mine

workers are not to be disabled by the dust they breathe”.

Twenty four mines were selected to embrace a wide range of

environmental and geological conditions. Techniques for measuring

dust exposure were developed. Men were grouped according to

various common tasks and assessments were made of the levels

of exposure associated with these. From these, estimates were

made of the cumulative dust exposure experienced by each man

in the survey. (The unit of dust exposure is ghm^-3

representing the product of dust exposure in gm^-3

of air and time exposed in hours). A programme of five yearly

medical surveys was instituted including assessment of respiratory

symptoms and smoking histories by questionnaire, chest X-rays

and spirometry. While much valuable information was gathered

about pneumoconiosis a large amount of data was collected

that revealed the existence of other respiratory disorders

among miners, i.e. chronic bronchitis and emphysema giving

rise to COPD. Data from the PFR constitute the most compelling

evidence that coal mine dust causes COPD but there are also

other sources of supportive evidence.