Occupational Health and Safety Act, 1993 (Act No. 85 of 1993)

Regulations

Regulations for Hazardous Chemical Agents, 2020

Annexures

Annexure 3 : Hazardous Chemical Agent Guidelines

Guidance on medical surveillance and biological monitoring

Applying occupational exposure limits

Limitations to the application of exposure limits
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61.The list of OELs, unless otherwise stated, relates to personal exposure to agents hazardous to health in the air of the workplace. The limits cannot be adapted readily to evaluate or control non-occupational exposure, e.g. levels of contamination in the neighbourhood close to an industrial plant. OELs are approved only for application to people at work. Although OELs are developed for atmospheric pressures between 85 kPa and 101,325 kPa, there are areas in South Africa where the atmospheric pressures are below 85 kPa. For practical purposes, uncorrected OELs may be used at atmospheric pressures as low as 80 kPa. Where higher atmospheric pressures may be encountered, for example, in tunnelling or underwater hyperbaric chambers, such situations will require special assessments. Guidance may be sought in the HSE guidance document "Occupational exposure limits for hyperbaric conditions", which is a hazard assessment document.

 

62. The OELs, as set out in Tables 2 and 3 of Annexure 2, are intended to be used for normal working conditions in workplaces. Employers should also take into account their duties and the provisions of the National Environmental Management Act, 1998 (Act No. 107 of 1998). OELs are not, however, designed to deal with serious accidents or emergencies, particularly where employees may be exposed to rapidly rising concentrations of gas, as may arise from a major escape due to plant failure. Over and above their responsibilities to ensure that the requirements of the HCA Regulations are met, employers also have a clear responsibility to ensure that the plant is designed, operated and maintained in a way that avoids accidents and emergencies. Where appropriate, detection, alarm and response measures should be used in order to minimise the effect of any such unplanned events. To help maintain adequate operational control, employers may find it helpful to select their own indicators of control when undertaking investigations or corrective action.