The Minister of Mineral and Petroleum Resources has published amendments to the occupational exposure limits for airborne pollutants, which will come into effect on 26 June 2025. A copy of the Government Gazette can be accessed here, which sets out the full table that will replace the current table under regulation 22.9(2)(a) of the Mine Health and Safety Act (MHSA).
Broadly, the amended table reflects a decrease in the prescribed occupational exposure limits across the South African mining industry. Notably, the revised table introduces prescribed limits for several pollutants not previously listed in the regulations, including:
Diesel Particulate Matter (DPM) - both elemental carbon and total carbon. Elemental carbon is listed as a carcinogen (a substance capable of causing cancer), with a permitted occupational exposure limit of 0.1mg/m3;
Metallic chromium as Cr(0) - with an occupational exposure limit of 0.5 mg/m3;
Chromium (metal and inorganic compounds) Cr(VI), water-soluble compounds - with a new short-term exposure limit (STEL) of 0.015 mg/m3.
Reductions in occupational exposure limits for other substances may also be of interest, including those applicable to asbestos, aluminum metal (respirable particulate), coal dust, and silica.
To ensure compliance with the amended regulations, employers must align their practices within the prescribed 90-day implementation period. This includes reviewing and updating current occupational hygiene risk assessments, codes of practice, and ensuring that all occupational hygiene surveys are conducted in line with the new exposure limits. Where enhanced protective measures are necessary, these must also be implemented accordingly.
