On 2 August 2024, the Chief Inspector of Mines issued a guideline directing mine operators to implement a new mandatory code of practice (COP) to better achieve quality assurance for measuring occupational hygiene and ventilation engineering. It outlines the following:
1.1 The
guideline will become effective on 1 November 2024 when employers in the industry are required to implement the new COP and update existing COPs that may be impacted by the provisions thereof, such as dealing with airborne pollutants, thermal stress and noise.
1.2 The guidance note provides essential instructions for employers at mines regarding the development and implementation of a mandatory COP focused on quality assurance in occupational hygiene and ventilation engineering measurements. The COP is mandated under Section 9(3) of the Mine Health and Safety Act (MHSA), ensuring that employers meet specific requirements concerning workplace environmental control, measuring, and monitoring.
1.3 Errors in processes such as sample collection, handling, preservation, and inadequate training are recognised as critical factors that affect the integrity of occupational health monitoring results. As such, key aspects to be included in the COP focus on ensuring that sampling and analytical results are accurate and reflective of the workplace conditions in which such measurements are taken. Quality assurance procedures are therefore an important step in addressing the potential shortcomings in the measurement or monitoring processes.
1.4 Employers are required to prepare and implement a quality assurance programme for the occupational hygiene and ventilation engineering measurement systems where risks that require measurement and monitoring are identified. This obligation arises from Regulation 9.2(2) read with Sections 11(4)(a) and 12 of the MHSA, which require that every employer must maintain a system of occupational hygiene measurements in workplaces with health hazards. Failure to do so constitutes a breach of the MHSA.
1.5 The scope of the guideline includes ensuring that the COP incorporates all elements of the occupational hygiene and ventilation measurement systems. The employer must document and regulate every step, from sample preparation to the interpretation and reporting of data. This documentation must be traceable and auditable, providing clear procedures for calibration, handling, and record-keeping.
1.6 Under Section 11 of the MHSA, employers are required to:
1.6.1 identify health hazards;
1.6.2 assess the risks employees may be exposed to;
1.6.3 record significant hazards and the measures taken to mitigate them; and
1.6.4 conduct a risk assessment methodology that accounts for the identification, evaluation, and recording of occupational health hazards.
1.7 The COP, therefore, must clearly state how the employer will control and monitor these hazards. The guidance note further underscores that employers should review and update the COP based on audit findings, changes in standards, or regulatory instructions. Compliance is not only required for internal purposes but may also be subject to external audits or investigations following accidents or serious health incidents.
Key elements for the COP
1.8 The mandatory COP must cover prescribed aspects of a quality assurance system to ensure a comprehensive framework within which employees tasked with the collection, sampling, transport, testing, recording and interpretation of data are adequately informed of the protocols in place to do so in a manner that safeguards the integrity of the data. As such, a core facet of a quality assurance system is the need for employers to define the roles, responsibilities, and qualifications of staff involved in monitoring and controlling occupational health risks.
1.9 The COP must further define the frequency, duration, and methods for sampling or measuring occupational health hazards, based on risk assessments. It must also outline protocols for calibration, equipment handling, and storage.
1.10 In addition, employers must develop systems to manage and calibrate the necessary equipment, with personnel adequately trained in its use.
1.11 The system should include procedures for identifying and mitigating sampling or measurement errors while ensuring all data is validated and interpreted before being reported.
1.12 Finally, employers are required to conduct internal and external audits on the quality assurance systems. Records, including risk assessment outcomes, equipment maintenance, and personnel training, must be systematically kept and updated.
Specific provisions
1.13 The guideline includes detailed requirements for facilities such as weighing rooms and establishes minimum standards for equipment handling and sampling accuracy. The weighing room, for instance, must be located in a controlled environment, ensuring the integrity of samples and minimising contamination from external factors like dust or static electricity.
1.14 Annexure C of the guidelines prescribes specific requirements regarding the information that must be recorded when field sampling is necessary. Such information includes allocating a unique survey number for each survey conducted together with a description of the purpose and date of the sampling with the hazards or parameters sampled set out as well. The unique identifiers or serial numbers of monitoring equipment must be recorded, and the medium of each sample must have a reference number if applicable eg filter reference number. Other field sampling data that must be recorded include, amongst others, the measurement method and analytical method applied, the personal protective equipment worn by those collecting the samples, and exposure sources. Environmental factors such as wind direction, wind speed, and humidity level, which might impact or influence the sampling procedure must be recorded to enable better data interpretation.
1.15 The COP required by this guidance note is a critical element of ensuring workplace health and safety compliance in mining environments. By adhering to these guidelines, employers will not only comply with the MHSA but also contribute to a safer and healthier working environment for employees.
1.16 Section 11(4) of the MHSA states: "Every employer must-
(a) periodically review the hazards identified and risks assessed, including the results of occupational hygiene measurements and medical surveillance, to determine whether further elimination, control and minimisation of risk is possible; and
(b) consult with the health and safety committee on the review".
1.17 Section 12 of the MHSA states: "Employer to conduct occupational hygiene measurements
(1) The employer must engage the part-time or full-time services of a person qualified in occupational hygiene techniques to measure levels of exposure to hazards at the mine-
(a) if required to do so by regulation or a notice in the Gazette; or
(b) if, after assessing risks in terms of section 11 (1), it is necessary to do so.
(2) Every system of occupational hygiene measurements must-
(a) be appropriate, considering the hazards to which the employees are or may be exposed; and
(b) be designed so that it provides information that the employer can use in determining measures to eliminate, control and minimise the health risks and hazards to which employees are or may be exposed.
(3) The employer must keep a record of all occupational hygiene measurements in terms of subsection (1) in a manner that can be linked as far as practicable to each employee's record of medical surveillance."
1.18 Regulation 9.2(2) of the Regulations in terms of the Mine Health and Safety Act:
"(2) The employer must establish and maintain a system of occupational hygiene measurements, as contemplated in section 12, of all working places where the following hazard limits prevail:
(a) airborne pollutants
- particulates 1/10 of the occupational exposure limit;
- gases and vapours 1/2 of the occupational exposure limit;
(b) thermal stress
- heat >25,0ºC wet bulb and/or >32,0ºC dry bulb and/or
>32,0ºC mean radiant temperature; - cold <10ºC equivalent
chill temperature; and
(c) noise
- 82dBLAeq,8h.