Human factors are an established science with a focus on understanding interactions among humans and other elements of a system. It applies theory, principles, data and methods to design in order to optimise human wellbeing and overall system performance.

Human factors applied to safety recognise the relationships and interactions between three types of components in the system which contribute to the likelihood and outcome of accidents, incidents and injuries. These are:

• organisation-related: management systems and organisational structure, shift and roster systems, roles and responsibilities, incentive schemes, contracts, etc.
• job-related: design of the workplace, work environment and the job, and the demands the job makes on people’s perceptual, cognitive and physical performance, including interpersonal interactions, etc.
• individual-related: skills, knowledge, attitudes, values, habits, personality, behaviours and other attributes individuals bring to the job.

Human factors focuses on understanding how human performance is shaped by conditions within the system. That is, what tasks people are being asked to do and the characteristics of the task, who is doing the tasks and their competence, and the environment in which people are working and its attributes.

Integrating human factors into safety management systems is important for achieving error-tolerant systems. While the focus of this information is on safety and safety management systems, it is also important to acknowledge that other systems such as human resources, performance management and contracting models within the organisation also influence human performance.

Integrating human factors into a safety management system does not mean creating a new section in the existing documentation. Operators can demonstrate how human factors have been considered in existing sections of the safety management system (SMS) documentation.

Safety management system documentation should clearly demonstrate how human factors have been considered in the management of risk. The risk management process does not change. The risk management process should include and demonstrate consideration of various aspects of the system on human performance in the areas of prevention, initiation, detection, control, escalation, mitigation and emergency response when identifying, assessing and controlling for major incident events (MIEs) and major accident events (MAEs).

For example, you may wish to describe how safety-critical tasks where human intervention acts as a control or safeguard against MIEs and MAEs are identified, including identifying performance-shaping factors, potential human errors and controls to reduce the risk by supporting the desired human performance.

The existence of a safety management system that does not consider human factors may not be sufficient to demonstrate the risks associated with MIEs and MAEs have been reduced to low as reasonably practicable (ALARP).

DEMIRS has guidance and tools to assist you in integrating human factors into your safety management systems.

Major accident and incident events are managed through risk control measures (barriers) and various safety management system elements ensure these risk control measures are effective and maintain their integrity during the entire lifecycle of a facility. 

Figure 1. Types of barriers and supporting SMS elements, Source: - Standardisation of Barriers Definitions: IOGP Report 544 (April 2016)

Controls should be targeted at the sources of risk within the system. This is done in the first instance through elimination controls followed by engineering, isolation and substitution controls.

Common controls to support desired human performance focus on equipment design, workplace design, task and job design, and design of processes and procedures, supervision, and monitoring.

Where there are safety-critical activities in which people act as the safeguard or barrier for major accident events and incidents, a safety critical task analysis (SCTA) should be carried out. The fundamental steps in a SCTA are:

1. Identify main hazards: focus on identifying the major accident hazards or major accident/incident events.
2. Identify and prioritise critical tasks: focus on tasks that can result in serious consequences and are vulnerable to human performance. You may need to prioritise the safety-critical tasks if many major accident hazards/major accident and incident events are identified.
3. Understand the tasks: identify who does what, when and in what sequence. Identify what tools and information are required.
4. Identify what could go wrong and why: consider human failures and the performance-shaping factors that affect human performance.
5. Determine and implement measures to control human failures: identify measures that will prevent human error as well as measures that will mitigate the consequence and increase recovery when human error does occur.
6. Monitor and review the effectiveness of the controls.

Human factors plays a vital role in emergency management. A prepared, well-rehearsed emergency management system will increase the likelihood that human performance will help mitigate the emergency or abnormal situation.

Preparation involves identifying likely emergency scenarios, developing emergency response plans including the equipment necessary and practising these plans regularly.

Key human factors vital for an effective and efficient emergency management system are:

• designating and recognised chain of command and control for implementing and managing the emergency response
• established selection criteria and assessment for allocating roles within the emergency response plans (seniority and job titles may not necessarily the best criteria)
• provision of training for allocated roles within the emergency response plan
• clear and well-rehearsed procedures that consider the strengths and limitations of human performance.  Fit-for-purpose job aids (summaries of responsibilities, checklists) can enhance human reliability
• appropriate staffing levels to implement an emergency response for different working arrangements (i.e. day, afternoon and night shifts, weekends)
• planned and well-rehearsed interfaces between various responders with all aspects of the emergency responses practised, at all levels (plant, on-site and off-site)
• effective communication arrangements to ensure all relevant parties (i.e. Department of Fire and Emergency Services, neighbouring sites, work health and safety regulator) are kept informed during the emergency or abnormal situation
• necessary equipment for emergency and abnormal situations is readily available and ready for use. Emergency response equipment should be inventoried and inspected routinely to ensure it exists, is in good condition and within its shelf life.

Further guidance and tools are available:

• DEMIRS Petroleum safety and major hazard facility – Guide Emergency planning
• Health and Safety Executive Inspectors Human Factors Toolkit
• NOPSEMA Emergency Planning Guidance Note

Applying human factors to incident analysis focuses on explaining ‘how’ and ‘why’ the event or incident occurred within the context of the situation. Building a detailed timeline of what occurred is important for understanding the contextual factors within the system which influenced human performance. These performance-shaping factors would have no influence if it weren’t for time. For example, workload, fatigue, distractions, problem escalation are meaningless without understanding the time constraints.

Examining the organisational-related, job-related and individual-related characteristics within the system to identify technical failures, as well as design-induced errors and human errors involves collecting data about these characteristics that are relevant to the event or incident. Collecting data from the following sources may be useful:

• workers involved in the event or incident
• recordings of performance parameters
• maintenance and integrity inspection records
• policies and procedures, and
• risk assessments.

Once you have explained how and why the event or incident occurred, the next step is to develop recommendations for improvement or prevention.

The following questions may assist in identifying recommendations or corrective actions to reduce the risk to as low as reasonably practicable:

• What types of human error occurred (e.g. memory, attention, precision)?
• What system components contributed to the human performance and can these components be designed out?
• Can the performance-shaping factors be changed to be more positive (e.g. developing a positive health and safety culture)?
• Can the human performance element be eliminated (e.g. by automation)?
• Can human performance be assured by using interlocks or other engineered means?
• Can the consequences of the error be prevented (e.g. by additional barriers and safeguards in the system)?

The key to effective incident analysis is to ensure that the approach used discovers the underlying reasons why an incident occurred, not just the error made by the last person involved.

Effective incident analysis is promoted by a ‘no blame’, ‘just’ or ‘learning’ culture – a culture that encourages incident reporting and examines performance-shaping factors within the broader system that led to the incident occurring, to make improvements to the system to reduce the likelihood of reoccurrence.

• Variation in human performance is normal and not causal. Variation in human performance is normal and to be expected given the strengths and constraints that come with being human. Human performance should not be capable of leading to a major event or incident on its own.
• Blaming human performance fixes nothing. Attributing the cause of a major incident to human performance is overly simplistic. More often than not, the performance is a symptom of wider systemic issues and even the best, most experienced, most competent people will make mistakes.
• Learning is vital. Organisational learning, driven by leadership commitment and continuous improvement or a learning culture, is fundamental for preventing re-occurrence. Opportunities for learning should be sought from all types of incidents: actual loss or harm incidents, near misses, and weak signals (i.e. small indications and signs that something is not correct or as it should be). 
• Context drives behaviour. Context is the meaning assigned to the situation. Context involves people’s beliefs, perceptions, motivations and values which shape human behaviour. People perform in ways that make sense to them, they adapt to the demands of the situation, assess risks and make trade-offs with good intentions. Understanding the contextual factors which drive behaviour helps identify underlying weaknesses in the system and opportunities to improve the system.
• How leadership responds matters.  Visible leadership commitment and modelling desired behaviours and attitudes is pivotal as workers take their cues from their management and the immediate work environment. A ‘just’, no-blame culture encourages reporting and improvement.

This information has been adapted from:

• Conklin, T. (2019), The Five Principles of Human Performance: A Contemporary Update of Human Performance for the New View of Safety. Independently published.
• Daniellou, F., Simard, M. and Boissières, I. (2011), ‘Human and organizational factors of safety: a state of the art’, Cahiers de la Sécurité Industrielle (Foundation for an Industrial Safety Culture) No. 11(01), Toulouse, France. Available at foncsi.org/en.
• Chartered Institute of Ergonomics and Human Factors, Learning from Adverse Events. Retrieved on 28 July 2021.

DEMIRS guidance

• Guide: Human factors fundamentals for petroleum and major hazard facility operators
• Guide: Human factors self-assessment guide and tool for safety management systems at petroleum and major hazard facility operators
• Human factors self-assessment tool for safety management systems at petroleum and major hazard facility operators – template

Other regulator guidance

Health and Safety Executive UK

• Human factors and ergonomics
• Framework for assessing human factor capability
• Inspectors human factors toolkit
• Development of a working model of how human factors, safety management systems and wider organisational issues fit together: Research Report 543 (2007).

The National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA)

• Human factors

Industry guidance

• Chartered Institute of Ergonomics and Human Factors: Human factors in barrier management
• Centre for Chemical Process Safety (CCPS) search for 'Human factors'
• Human Performance Oil & Gas: global resource of guidance, best practice and accessible worksite tools to further implement human performance efforts across the oil and gas industry
• ICheme central database of resources on major hazard management and human factors
• International Association of Oil & Gas Producers (IOGP) search for ‘Human factors’.
• International Association of Oil & Gas Producers (IOGP): Report 454: Human Factors Engineering projects (2020).

Free information sessions

• Chartered Institute of Ergonomics and Human Factors 
• Human Performance Oil & Gas: Chartered Institute of Ergonomics and Human Factors (CIEHF) Human Performance for ALL