Reduction of respirable silica following the introduction of water spray applications in Indian stone crusher mills.

Respirable crystalline silica dust generated during stone crushing operations has been linked to chronic lung disease and increased risk of tuberculosis. In India, most stone crushing mills operate without any dust control or containment systems. This investigation in the Khurda District of Orissa demonstrated a reduction in respirable particulate mass following the application of a fine mist of water. Average respirable quartz and cristobalite levels declined 82% and 69%, respectively, after water spray controls were installed. This finding suggests that relatively inexpensive modifications that are available in the local market can be effective at reducing silica exposures. Although average exposure levels, particularly during the dry season, may exceed the Permissible Exposure Limit for silica, the overall reductions observed were substantial. Widespread adoption of this simple control technology by stone crushers in India could have a positive public health impact.