The Productivity Puzzle: 8-Hour vs. 12-Hour Shifts in Mining
The mining industry operates around the clock, demanding efficient and productive operations. A key decision in achieving this lies in shift scheduling.
Mines typically operate on either 12-hour or 8-hour shift schedules. An 8-hour shift typically involves three crews rotating throughout the day, while a 12-hour shift involves two. While 8-hour shifts are common in many industries, the allure of increased output has driven the majority of global mines to adopt 12-hour shifts. However, the path to higher productivity is not always as straightforward as it seems.
How do they compare?
Proponents of 12-hour shifts often champion their potential to significantly boost production. By reducing the number of shift changes, these schedules minimise downtime associated with shift handovers. This uninterrupted flow of operations, particularly in continuous processes like load and haul operations, can lead to a more consistent and efficient production stream. Studies have shown potential output increases of 5-10% in some cases, but these figures can vary significantly depending on the specific mining operation and its unique challenges. Furthermore, fewer shift changes often translate to lower employment costs, as less operators would be required and fewer supervisors would be needed to oversee operations. This simplification can potentially lead to increased efficiency and reduced operational costs.
However, the potential benefits of 12-hour shifts must be carefully weighed against their potential drawbacks. Extended work hours can significantly increase the risk of employee fatigue. While rest breaks are crucial, the cumulative effects of prolonged exertion can lead to diminished alertness, slower reaction times, and ultimately, an increased risk of accidents. This not only jeopardizes worker safety but also disrupts production flow through increased likeliness of unplanned downtime and potential equipment damage events. Moreover, these extended shifts can often result in decreased morale, higher employee turnover, and ultimately, a negative impact on long-term productivity. Therefore, whilst the 12-hour shifts provide the opportunity for significant productivity increases, the potential pitfalls of this pattern must also be considered.
Mitigating the impacts of each shift structure
Mitigating the challenges of 12-hour shifts requires a multi-faceted approach focused on fatigue management and safety. This can be achieved through:
Incorporating distraction safety systems, such as driver fatigue monitoring and collision avoidance technologies, can help alleviate the risks associated with operator fatigue.
Good site-wide lighting and visibility are crucial, especially during night shifts, to mitigate accidents and improve overall safety.
Fatigue tracking dashboards and tools provide valuable data, allowing supervisors to monitor operator fatigue event trends and identify individuals who might be struggling.
Regular breaks, access to healthy food and hydration, and educational programs on sleep hygiene and fatigue management are essential.
Promoting a culture of open communication where workers feel comfortable reporting fatigue or concerns is also vital. This could include the regular review and adjustment of schedules based on employee feedback and operational needs.
For 8-hour shifts, the primary challenge lies in minimising downtime during shift changes. Streamlined shift handovers are crucial. This can be achieved through:
Standardised shift handover forms that provide incoming teams with all the necessary information, significantly speeding up the process and removing levels of ambiguity and/or problem diagnosis commonly seen in shift handovers.
Strategic scheduling, particularly in relation to blasting schedules, can further enhance productivity. For example, aligning blasting with handover windows can minimise disruptions during the shifts, whilst allowing for multiple blasts per day, maximising the potential of these additional periods of reduced mobile fleet activity.
Clear communication protocols, well-defined roles and responsibilities, and regular training on handover procedures can all contribute to a more seamless and productive shift-change process.
Regardless of the shift pattern, a site should always ensure that operator shift patterns match the shift pattern of the office operations teams. Misaligned shift schedules between field operations and support teams (e.g., dispatch, maintenance) can create significant inefficiencies, communication breakdowns, and delays. Ultimatley, to get the most out of any shift pattern, all of the above points should be considered in order to maximise productivity and safety on a site.
Conclusion:
The “optimal” shift length is not a one-size-fits-all solution. The most productive schedule depends on a multitude of factors, including the specific mining operation, the nature of the work, and the prevailing safety culture. While 12-hour shifts may offer the promise of increased output, a comprehensive assessment of their impact on safety, employee well-being, and operational flexibility is crucial.