Environmental conditions at Pentremawr Colliery, 1968

This report tabulates respirable dust concentrations (mg/m3 ) for the period May to October, 1968 at Pentremawr Colliery, and is the first report in which all dust measurements have been made using the M.R.E. Gravimetric Sampler only. Information regarding methods of working, outputs and manpower is given. For each face occupation, the concentrations of respirable dust, together with ash and quartz concentrations for each face site are listed.Pentremawr Colliery, where the coal is won by hand filling methods, had a coalface (all shifts) mean respirable dust concentration of 2.2 mg/m3. The ash content of the respirable dust was 22.3 per cent and the percentage of quartz in sample was 2.3 (concentration 0.05 mg/m3). “”