Fatigue Risk Management for the UK Heavy and Light Rail Industry

Tuesday, December 12, 2023

In its Annual Report on the Health and Safety on Britain’s Railways, published in July 2023(1), the ORR (Office of Rail and Road), highlighted that fatigue management remains a focus area for continued review and improvement. Recent investigations(3,5) by the RAIB which find discrepancies in operators’ Fatigue Risk Management Systems (FRMS) also support that there are improvements to be made within the industry. This article provides a view on how those within the UK Heavy and Light Rail industry can act to improve the effectiveness of their FRMS, based on our years of experience supporting operators implementing FRMS.

The ORR defines fatigue as “a state of perceived weariness that can result from prolonged working, heavy workload, insufficient rest and inadequate sleep”, reducing the ability of an individual to work safely and effectively. Whilst some effects of fatigue may appear obvious, such as unintentionally falling asleep, workers can be unaware of how much their performance is being adversely affected by fatigue, including any lapses in attention or microsleeps (brief periods of unintentional sleep). This means the risks associated with fatigue must be managed systematically, rather than only relying on individuals to act when they experience elevated fatigue levels.

Managing fatigue effectively also provides business benefit. Workers who are too fatigued to work safely may report sick rather than as being fatigued, meaning that not only is that worker lost to the business for the day, but also no data is collected on the causes of that fatigue. This data could inform strategies to reduce fatigue and therefore the likelihood of that individual – or others in a similar circumstance – being too fatigued to work safely in the future. Training is a significant cost across multiple industries, and the rail sector is no exception. Evidence clearly shows that fatigued individuals pick up skills more slowly and are worse at retaining information. This increases training durations and associated costs. In many organisations, elevated fatigue is also associated with inefficiency – reducing fatigue levels can increase roster efficiency and effectiveness.

The regulatory requirement to manage the fatigue of the workforce in the UK Rail sector is long-standing. It is outlined under Regulation 25 of the Railways and Other Guided Transport Systems (Safety) Regulations (ROGS, 2006). In 2012, the ORR best practice guidance for fatigue risk management was published in Managing Rail Staff Fatigue(2), alongside a call for Fatigue Risk Management Systems (FRMS) to be part of the wider Safety Management System in organisations with safety critical workers, and/or where the risks of fatigue are higher due to shift work or long working hours.

Fatigue Risk Management Systems are an evolution and specialism of Safety Management Systems. This systematic application includes multiple levels of controls, and recognises that limiting hours of work in isolation is insufficient to manage the risk of fatigue. For example, prescriptive limitations which outline minimum rest periods between work periods do not guarantee sufficient sleep – factors such as commuting and the time of day the rest period is taken are usually not considered, but can have a big impact on sleep duration. A comprehensive data-driven FRMS manages risk holistically and is embedded in the culture of an organization. An effective FRMS will ensure the best safety outcomes, protect the long-term health and wellbeing of staff, and reduce the risk of reputational damage and potential associated costs to an organisation. However, to reach this effective position requires ongoing effort from the organisation, and buy-in across all levels, from senior leadership through to all members of the workforce.

Key components of FRMS should include:

  • Using a data driven approach to identify, mitigate and manage fatigue risks, which include multiple sources of data to capture the complete fatigue ‘picture’
  • Ensuring competence across the workforce, both for those who may experience fatigue, and those who may influence the fatigue of others
  • A shared responsibility for managing fatigue between the organisation and individual workers

To effectively implement an FRMS, ORR recommends a POPMAR(6) approach:

  • Policy
  • Organising (i.e. developing your organisation, identifying roles and functions)
  • Planning and Implementing (Where are you now? How do you get to where you want to be? Training all appropriate members of the workforce, comparing working patterns to the fatigue factors)
  • Measuring Performance (measuring fatigue in actual operations, fatigue reporting, use of fatigue models, fatigue surveys and incident investigation)
  • Auditing and Reviewing Performance (Key Performance Indicators, internal and external audits for compliance and effectiveness, feeding back to FRMS improvements)

Ensuring that all these elements are in place is key to ensuring an effective FRMS. The final step (Auditing and Reviewing Performance) should inform you where there are gaps – as does learning from others within the industry.

Whilst FRMS is a regulatory requirement under the ROGS, it is not uniformly and effectively applied throughout the industry. In an accident report published in 2022(3), the Rail Accident Investigation Branch (RAIB) noted that a review of the operator’s FRMS found it did not follow current industry guidance and good practice, resulting in a recommendation being made by the RAIB to the operator regarding its FRMS.

The operator was utilising the HSE Fatigue and Risk Index (HSE:FRI), a bio-mathematical model designed to predict fatigue levels according to work shifts, sleep opportunities and circadian factors that is used widely across the industry. However, the model was used in isolation as a means of identifying fatigue associated with working patterns. Best practice recommends that multiple means of identifying fatiguing patterns are used, including comparing working patterns against the ORR ‘fatigue factors’(4) i.e. time of day, duty length, intervals between duties, recovery time, cumulative fatigue, and circadian phase shift factors.

Without using all these elements, it is not possible to demonstrate that fatigue is being effectively identified and managed, in accordance with the requirements of Regulation 25 of the ROGS. A broad assessment of your FRMS, looking at the components and effectiveness of the FRMS can highlight any gaps or weaknesses. Baines Simmons has undertaken assessments – called Fatigue Risk Management Diagnostics – for operators within both heavy and light rail, allowing the organisations to meet their regulatory obligations, manage risk effectively, and gain operational benefits from effectively managing fatigue risk.

Bio-mathematical fatigue models are used widely in the rail industry. They are useful for predicting fatigue levels and ‘hotspots’ where high levels of fatigue are likely, supporting fatigue risk management when used alongside other tools. These software tools usually calculate average fatigue levels, and need to be used with a clear understanding of what the results do and do not consider (for example most models do not consider workload effectively), and what ‘threshold’ values mean.

Understanding and identifying appropriate thresholds is a key decision for those managing the FRMS, and must be appropriate to different workgroups, according to their role and working patterns. For example, in the HSE:FRI, the fatigue scores range from 0-100, with a Fatigue Index Score of 50 representing a 50% chance of employees achieving a Karolinska Sleepiness Scale (KSS) score of eight or nine. In the KSS a score of one reflects being extremely alert whilst scores of eight or nine reflect high levels of sleepiness, where microsleeps are highly likely. Research by the Health and Safety Laboratory (HSL) and the ORR found that the majority of working patterns in the rail sector produced HSE:FRI fatigue scores of 30-35 for day shifts and 40-45 for night shifts – and these values have subsequently been used as ‘thresholds’ by many within the rail industry. However, the report did not aim to identify safe thresholds.

Rather, individual TOCs should identify the level of fatigue risk that they are willing to accept in their own operation and manage this risk through their FRMS. The identified thresholds, and subsequent use of the model should reflect that operators should control fatigue risk to As Low As Reasonably Practicable (ALARP) – always seeking to reduce the risk, unless the means of further mitigation are grossly disproportionate.

Even where the working pattern has been designed to reduce fatigue risks as far as possible, disruptions, overtime, elevated workload, or personal difficulties of the worker can still result in elevated fatigue on the day. This is where another critical barrier comes in – the ability of a worker to remove themselves from work due to fatigue, supported by fatigue reporting. Another RAIB report, published in 2023(5) found there were no effective channels for safety critical workers to express if they are experiencing high levels of fatigue or to declare themselves unfit for duty. For fatigue reporting to work as an effective part of the FRMS, many elements must be in place:

  • Workers are competent to recognise when they are no longer fit to operate safely, and know what steps to take to reduce risk
  • Company culture means that declaring yourself unfit due to fatigue is welcomed as a positive safety action. Or are there fears of negative consequences?
  • Other policies do not conflict with removing oneself from duty due to fatigue, such as absence management, or communications regarding avoidance of delays
  • The organisation monitoring instances of fatigue to identify common themes, and acting to reduce them where possible.

When the FRMS is working effectively, not only can you identify new contributors to fatigue, but also measure the effectiveness of mitigations, and identify where fatigue may have played a role in incidents or near-misses. Using the mitigations and planning rosters with the intent to reduce fatigue can also support reducing absences, alongside the associated reduction in risk. For example, through an effective FRMS, fatigue reporting and near-miss data may indicate that there is elevated fatigue on consecutive early shifts, or at the end of night shifts, despite planning according to the fatigue factors, and using the HSE:FRI.

Mitigations then need to be implemented to reduce the risk, such as adjusting the shift pattern, shortening shifts, or adding breaks to ensure fatigue risk is controlled to an As Low As Reasonably Practicable (ALARP) position. However, if the reports or incidents are from a small number of individuals, mitigations may also be applied at an individual level – such as providing support or discussing alternative shift patterns. No matter the origin of the reported fatigue, feedback and ongoing monitoring of the controls put in place are essential, and form part of the Auditing and Reviewing element of the FRMS.

Operating Companies in both Heavy and Light Rail in the UK have used FRMS principles for many years, given how long the requirement to manage fatigue has been in place. However, there is still further work to do to ensure that the FRMS is effective, that fatigue is truly being managed, and the companies and the workforce can reap the benefits of effectively managed fatigue. Both the ORR and the RAIB are calling for improvements to be made – as an operator, are you comfortable with your current approaches?


1. https://www.orr.gov.uk/monitoring-regulation/rail/promoting-health-safety/annual-health-safety-report
2. Managing Rail Staff Fatigue January 2012. Office of Rail Regulation
3. https://assets.publishing.service.gov.uk/media/62f1228e8fa8f5032b58cee0/R072022_220811_Kirkby.pdf
4. https://www.orr.gov.uk/sites/default/files/2021-12/good-practice-guidelines-fatigue-factors.pdf
5 https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1167991/R132022_221109_Enfield_Town.pdf
6. Managing Rail Staff Fatigue January 2012. Office of Rail Regulation