Chest x-rays can detect the early signs of and changes in CWP, often before the miner is aware of any lung problems.A 2016-17 investigation by National Public Radio found that the National Institute for Occupational Safety and Health had under-reported cases of progressive massive fibrosis (a complication of black lung) by at least a factor of 20. NPR identified over 2,000 cases at certain clinics in Kentucky, Virginia, West Virginia, Pennsylvania, and Ohio, compared to 99 that NIOSH reported. NIOSH confirmed in 2018 the largest cluster of PMF ever scientifically documented, despite near-elimination of the disease in the 1990s. The causes of the spike are believed to include longer working shifts, mining of thinner coal seams (which causes mining machines to put more non-coal silica dust in the air), and retirements and layoffs that have prompted more former employees to visit health clinics.New U.S. Mine Safety and Health Administration rules took effect in August, 2016, that lowered maximum allowed dust concentrations for surface and underground mines, and exposure by miners who have been found to be developing pneumoconiosis. Research
Work to investigate the relationship between respirable dust exposure and coal workers pneumoconiosis was carried out in Britain by the Institute of Occupational Medicine. This research was known as the Pneumoconiosis Field Research (PFR). The research underpinned the recommendations for more stringent airborne dust standards in British coalmines and the PFR was ultimately used as the basis for many national dust standards around the world.
Focal emphysema extends into progressive centrilobular emphysema. Less commonly a variant of panacinar emphysema develops.Continued exposure to coal dust following the development of simple CWP may progress to complicated CWP with progressive massive fibrosis (PMF), wherein large masses of dense fibrosis develop, usually in the upper lung zones, measuring greater than 1 cm in diameter, with accompanying decreased lung function. These cases generally require a number of years to develop. Grossly, the lung itself appears blackened. Pathologically, these consist of fibrosis with haphazardly-arranged collagen and many pigment-laden macrophages and abundant free pigment. Radiographically, CWP can appear strikingly similar to silicosis. In simple CWP, small rounded nodules (see ILO Classification) predominate, tending to first appear in the upper lung zones. The nodules may coalesce and form large opacities (>1 cm), characterizing complicated CWP, or PMF. Diagnosis
There are three basic criteria for the diagnosis of CWP:

Chest radiography consistent with CWP
An exposure history to coal dust (typically underground coal mining) of sufficient amount and latency
Exclusion of alternative diagnoses (mimics of CWP)Symptoms and pulmonary function testing relate to the degree of respiratory impairment but are not part of the diagnostic criteria. As noted above, the chest X-ray appearance for CWP can be virtually indistinguishable from silicosis. Chest CT, particularly high-resolution scanning (HRCT), are more sensitive than plain X-ray for detecting the small round opacities. Treatment
There is no cure or discovered treatments for pneumoconiosis. Some patients are given oxygen to help with their breathing and are advised to stop smoking to prevent further decline in lung function.