How to Improve the Accuracy of Coal Mine Dust Sampling

The development of control technology for reducing respirable dust in coal mines has been hindered by the difficulties involved in making accurate dust measurements. Recent Bureau of Mines research has provided new insights into the causes of measurement errors, and how to minimize them. Improving the accuracy of coal mine dust sampling involves five basic steps: 1) use of modern equipment, such as flow-regulated gravimetric pumps and instantaneous dust monitors; 2) avoiding, to the extent possible, sampling locations with a steep concentration gradient; 3) ensuring that the airstream being sampled is representative of the source; 4) alternating the operation (on vs. off) of the control technology as frequently as possible to minimize dust level changes due to changes in material being cut or production; and 5) pinpointing dust sources to ensure that the dust being measured relates to the control being tested.