The use of water spray systems for respirable dust control on continuous mining machines has been a traditional and relatively effective approach. However, with the implementation of more stringent dust standards due to quartz, the efficacy of these systems has been questioned. In response, the U.S. Bureau of Mines has undertaken a study to determine the relationship between spray pressure, total respirable dust control, and specific quartz dust control. Laboratory and full-scale model studies have been completed in an effort to evaluate the effectiveness of low- pressure, high-pressure, and combination water spray systems. Results of these tests indicate that high-pressure atomized sprays will improve reduction of all respirable dusts, especially dust in the 3.0-Um size range and below. These are also the size ranges that have been shown to contain the most significant amounts of airborne respirable quartz dust. Improved control techniques, such as those presented in this article, may be required in mine sections where more stringent dust standards are in effect.