Research Question
What are the effects of cannabis on occupational health and safety in the South African Mining Industry (SAMI) and what is the maximum allowable level of cannabis in the body system while at work?

Key Findings

• The decriminalisation of cannabis presents significant health and safety risks within the SAMI, particularly in safety‑critical and high‑risk work environments.
• Delta‑9‑tetrahydrocannabinol (THC) concentrations below 1 ng/ml are generally associated with minimal impairment, while impairment increases in a dose-dependent manner at higher concentrations. Clinically meaningful impairment is typically observed at levels of 2 ng/ml and above, representing a material risk to safe work performance in safety‑critical environments.

Key Recommendations

1. Policy and Code of Conduct Revision

• The Alcohol and Substance Abuse Policy and the Code of Conduct should be updated to explicitly incorporate cannabis use, its associated risks, and the consequences of non‑compliance.
• The revision should clearly outline that breaches may result in disciplinary action, including possible dismissal, in line with the Law of Contract and the employer’s obligations under the Mine Health and Safety Act No. 29 of 1996 (MHSA).

2. THC Cut‑off Limits for Safety‑Critical Work

The revised policy should adopt the following allowable THC thresholds:

• Safety‑Critical and High‑Risk Work
  • No employee performing work in dangerous environments—such as operating machinery, equipment, vehicles, or any movable objects—may have a blood THC concentration exceeding 1 ng/ml while on duty.
• General Work Environments
  • No employee may have a blood THC concentration exceeding 2 ng/ml while at work, regardless of job category.

3. Revision of Drug Testing Procedures

• Existing drug testing protocols, assessment tools, and screening methodologies should be updated to include cannabis‑specific provisions, including validated testing methods and impairment indicators.
• All employees, contractors, and service providers must be inducted on the revised procedures to ensure consistent understanding and compliance.

4. Cannabis Surveillance and Monitoring

• Cannabis monitoring should be integrated into the existing risk‑based exposure surveillance framework, including:
  • Initial (baseline) examinations
  • Periodic, routine, or ongoing surveillance
  • Exit medical examinations

• This ensures alignment with occupational hygiene and occupational medical surveillance requirements under the MHSA.

Research Question
Is the Heat Tolerance Screening Test (HTS) an adequate tool to assess if an employee is heat tolerant and are the methods used to determine heat tolerance valid?

Key Findings

• The current HTS tool is adequate, valid, and effective for its intended purpose of identifying heat‑intolerant workers. Evidence indicates that the tool itself is not the cause of HTS test failures within the South African Mining Industry (SAMI).

• HTS failures primarily arise from suboptimal implementation of HTS protocols and reduced physical conditioning among workers, rather than deficiencies in the tool.

Key Recommendations

1. Strengthen Pre‑HTS Medical and Functional Screening

• Comprehensive medical evaluations, fatigue assessments, and physical and functional work‑capacity assessments should be conducted before referring workers for HTS testing.

• This ensures that only medically and physically suitable individuals undergo HTS, reducing unnecessary failures and improving worker safety.

2. Implement an Integrated HTS Data and Monitoring System

• An integrated digital HTS data storage and transfer platform should be established to improve data integrity, traceability, and decision‑making.

• The system should integrate with other centralised digital functionalities including:
  • Sensors within climatic chambers for continuous environmental monitoring
  • Heart‑rate monitoring technology for real‑time physiological data synchronisation

• This will enhance accuracy, standardisation, and early detection of abnormal responses during testing.

3. Strengthen Quality Control Measures

Quality assurance for HTS processes should include:

• Routine HTS audits to ensure consistent application of protocols
• Enhanced hygiene standards for climatic chambers, thermometers, and related equipment
• Upskilling and continuous professional development for HTS personnel
• HTS awareness induction for general staff to improve understanding of the process and its purpose
• Structured heat‑acclimatisation programmes for workers exposed to hot working environments

These measures will improve reliability, reduce procedural variability, and support compliance with occupational health standards.

4. Enhance Ongoing Heat Stress Management

To strengthen long‑term heat‑stress resilience across the workforce, operations should implement:

• Reinforced fatigue‑awareness initiatives to reduce risk‑taking and improve self‑monitoring
• Healthy‑lifestyle programmes promoting hydration, fitness, and cardiovascular conditioning
• Wearable technology to support self‑pacing, early heat‑strain detection, and real‑time alerts
• Advanced skills training to improve workers’ ability to maintain body cooling and respond effectively during heat‑related emergencies

These interventions support a proactive, risk‑based approach to heat‑stress management in line with Mine Health and Safety Act No. 29 of 1996 requirements.

Research Question

Is the current Crystalline Silica Dust Exposure Medical Surveillance System comprehensive enough to monitor all organs’ adverse health outcomes in the South African Mining Industry (SAMI)?

Key Finding

Although a mandatory Code of Practice for Crystalline Silica Dust Exposure Medical Surveillance exists within the SAMI, it is not comprehensive enough as it excludes cardiovascular, renal, and autoimmune systems from monitoring, highlighting the need for a more comprehensive framework to detect the full range of silica‑related health effects.

Key Recommendations

• Regulation 11.7 of the Mine Health and Safety Act No. 29 of 1996 and the Mandatory Code of Practice for respirable crystalline silica dust exposure (DMRE 16/3/2/4-A1) should be updated to include the following examinations:
  • Cardiovascular examinations to detect Cor Pulmonale and Cardiovascular Disease (CVD)
  • Renal examinations to detect Chronic Kidney Disease (CKD) and End-Stage Renal Disease (ESRD)
  • Autoimmune examinations to detect Rheumatoid Arthritis (RA), (Systemic Lupus Erythematosus (SLE) and Multiple Scleroderma
• DMRE 16/3/2/4-A1 should also be updated to recommend that Tissue Biopsy, Diffusing Capacity for Carbon Monoxide (DLCO) test, Bronchoscopy, Computer Tomography (CT) scans, Sputum test and Skin test be added to the existing cardiorespiratory tests for more enhanced medical screening of pneumoconiosis.

Research Question

What is the capacity of mine health facilities in the South African Mining Industry (SAMI) to accommodate surrounding communities?

Key Finding

It was determined that mine health facilities in the SAMI DO NOT have the capacity to provide healthcare services required by surrounding communities.

Key Recommendations

• Business case for a co-funding partnership operating model between mining operations, the government, and private investors.
• Expansion through mobile clinics to neighbouring communities.
• Intermittent provisioning of selected healthcare services to the communities at pre-determined intervals incrementally.
• Running health care programs and awareness campaigns to promote preventative healthcare.
• Consider provision of healthcare services at cost to adjacent communities.

Research Question

How can we best monitor behaviour changes from the people-entered interventions adopted as part of leading practices?

Outcome

A Continuous Improvement Model was recommended which includes a continuous cycle of identifying, training, implementing, monitoring, obtaining/providing feedback and improving desired behaviours.