Muhandisī-i bihdāsht-i ḥirfah/ī (Dec 2020)
Application of Arc-GIS for Zoning of Occupational Exposure Levels to Respirable Crystalline Silica in Crushing Factories
Abstract
Background and Objective: Silica crushing is a process based on crushing, sieving, and granulating various types of siliceous rocks. The inhalation of silica dust leads to silicosis by imposing structural changes and irreversible fibrosis in the lung tissues. The crystalline silica is classified as a human carcinogen (Group 1) by the International Agency for Research on Cancer. Azandaryân region, Hamadan Province, Iran, is one of the largest silica production units in Iran with 40 silica crushing factories. This study was conducted to investigate the application of Arc-GIS in the zoning of occupational exposure to respirable crystalline silica (RCS) in this region. Materials and Methods: In this descriptive study, the individual exposure levels to RCS were measured among 16 workers in silica crushing factories according to the National Institute for Occupational Safety and Health method No. 7602. Moreover, 16 air samples were collected and quantified simultaneously to evaluate the environmental concentrations of RCS in the studied factories. Results: The results showed that the mean score of individual exposure level (2.01±2.61 mg/m3) exceeded the occupational exposure limit proposed by the Iran Technical Committee of Occupational Health for 8 working h (0.025 mg/m3). It was also found that there was a significant difference between the mean of individual exposure concentration and RCS in the different job activities (P=0.001). Conclusion: The results showed that the individual exposure levels had no significant relationship with environmental concentrations of the RCS. Furthermore, geographic information system had a desirable potential for zoning occupational exposure levels to RCS in workplaces. The findings of this study also emphasized the application of other modeling methods to determine the amount of silica emission in different units of the silica crushing factories.
