Study on classification of dust hazards in stone processing industries in Shanghai

Objective The classification of dust hazards in stone processing industries was done to provide basic information for the governmental supervision. Methods One hundred and twenty stone processing industries in Shanghai were investigated. The dust levels at workplaces were measured and classification was made according to the national guideline. Results The workplaces involved in silica dust (50% < free SiO₂ ≤ 80%) were ranked as high risk, while the workplaces involved in marble dust were ranked as low risk. The process with water-milling had lower risk compared with that with dry-milling, cutting or sawing. Conclusion Stone processing industries should improve technology and install protective facilities in order to decrease the airborne dust concentration at workplaces.