Prolonged exposure to silica dust may cause silicosis and silico-tuberculosis in stone quarries and stone crushing factories. Government has no information as to whether cases of silicosis are increasing in the country.

No death caused by silicosis has been reported to the Directorate-General of Mines Safety by mine management during the last three years and the current year. In case of stone crushing units, no case of silicosis has been reported from the States except two cases of silicosis from the State of Gujarat.

The steps taken by the Government to prevent air pollution include the following:

1. Model Rules have been framed on manipulation of stone or any other material containing free silica under Section 87, of the Factories Act, 1948. The said Schedule contains provisions relating to precautions in manipulation such as damping the stone, providing water spray, enclosing the process, isolating the process, providing localized exhaust ventilation and maintenance of the floors etc. for prevention and control of particulates.

2. Stringent National Ambient Air Quality Standards have been notified recently under the Environment (Protection) Act, 1986.

3. The Coal Mines Regulations, 1957 and Metalliferous Mines Regulations, 1961 provide for wet drilling & use of dust extractors in metal mines, wet cutting & use of dust extractors in coal mines with periodic monitoring of work environment for measures to keep respirable dust within permissible limits, monitoring of airborne dust through regular sampling and analysis, taking control measures where permissible limits exceed and use of personal protective equipments like dust respirators.

4. Emission standards have also been notified under the Environment (Protection) Act, 1986 in respect of suspended particulate matter (SPM) to reduce / contain dust from stone crushers. In addition, the units are also required to adopt following control measures:

- Dust containment cum suppression system for the process equipment. – Construction of wind breaking walls. – Construction of the metalled roads within the premises. – Regular cleaning and wetting of the ground within the premises. – Growing of a green belt along the periphery of units.

This information was given by Shri Ghulam Nabi Azad Minister Union Minister for Health & Family Welfare in the Lok Sabha