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The design of modern control rooms has benefited a great deal from ergonomics and resulted in working environment, furniture and human-machine interfaces that are more consistent with the needs of the people who work in them. However, focusing on these factors can lead designers to assume that using the latest technology and following the most up to date standards will result in a successful control room. This overlooks the fact that a control room is only a component in a complex system where people and equipment come together to control that system.
This paper explores the fact that any project developing a new or upgraded control room can have a significant impact on a wide range of human factors. It considers the role of the operator, taking into account the reality of what actually happens in the control room. It identifies how these activities can cause harm, both to the health and safety of the operator; and through the failure to control major hazards and process risks. It describes a number of techniques that can provide some structure and assistance in carrying out these assessments. Also, it suggests a number of areas where specific attention is required to control the risks of control room operations.
Control room operations have changed over recent years, and this has affected the risks that need to be managed. For example, in the process industry, technological advancements during the nineteen sixties and seventies allowed plant sizes and throughputs to increase significantly, and risk management was focussed on the magnitude of potential accident hazards. More recently the industry has become far more mature. There is less technical innovation and more focus on cost. This has resulted in increased automation and reduced staffing levels. Therefore, although the magnitude of hazard for a plant may not have increased, the magnitude per operator has, and this is why the focus for risk management needs to change.
In other industries similar trends can be observed. For example, new technology means air traffic and railway control centres can cover wider areas; requiring less control rooms and less people. Aircraft and ship autopilots are having an increased role. There is no reason to avoid using this technology, but the risks need to be fully understood and controlled.
CONTROL ROOM ACTIVITIES
What is a control room?
A control room is generally defined by its design, use and location. These characteristics impact on both technical and human factors, which must be considered together to fully understand how a control room functions.
Control rooms allow people to control a system from a remote or centralised location. This fundamentally affects the way they interact with the system. Typically a control room operator is required to rely on technology and other people to relay information about the system they are controlling. They then interpret that information to determine what is happening and whether action is required. Technology and other people are then used to carry out those actions.
New technology has had a big impact on control room operations. In the past there were physical limitations that affected how far a control room could be from the plant and equipment being controlled. Digital systems do not have these limitations, whilst also allowing high degrees of automation. This has had a significant impact on the control room operators’ job and their relationship with their colleagues and the systems they control. Unfortunately, the introduction of technology has tended to be focussed on what is technically possible, without fully considering what is desirable for the people involved.
What do control room operators do (in reality)?
The obvious answer to this question is that control room operators ‘operate’! However, this implies some level of action, which may not accurately reflect reality in many control rooms. Therefore, an alternative answer could be that they ‘monitor.’ This is probably more representative of what they do most of the time, but it is such a passive activity, it is unlikely that anyone would find it stimulating enough to provide any level of job satisfaction or motivation. Given that in many industries the control room operator has the most critical role in ensuring safe and efficient operations, it is vital that we have a better idea of what they do if we are to understand the risks fully.
The reality is that operators working in a modern control room are involved in a range of activities. Whilst some are clearly recognised as operations, many in the past would have been a supervisor’s responsibility. Also, organisational changes (e.g. introduction of ‘self managed’ and ‘multi-skilled’ teams) mean that teams are smaller and some of the more humdrum activities are now performed in the control room. The following is an illustrative list of what control room operators actually do, in addition to operating the plant:
• Communicate with others people inside the control room;
• Communicate with people in other locations;
• Answer telephones;
• Conduct shift handovers;
• Carry out administrative tasks;
• Eat meals;
• Coordinate non-routine activities (e.g. give permission for work to start, issue permits-to-work etc.);
• Read and send emails;
• Training (for themselves and others);
• Inputting maintenance requests;
• Etc.
As well as the above tasks performed during ‘normal’ situations, the control room also acts as a ‘hub’ during emergencies. In addition to responding to the operational aspects of the emergency, the control room operator may be involved in:
• Raising the alarm;
• Notifying emergency services;
• Co-ordinating communications between the parties responding to the event;
• Keeping a log;
• Conducting the roll call.
These activities during normal and abnormal situations can have a significant impact on safe and efficient operations and need to be understood fully in order to successfully manage the risks.
Changes in the control room
Automation has had a significant impact on what is done in the control room. As well as reducing the number of people needed, it has also reduced the physical nature of the operators’ job and increased the level of passive monitoring that takes place. It has increased areas of responsibility and the ability to achieve greater levels of control has meant that more hazardous operations can be carried out.
Experience has shown that installing new technology without adequate consideration of human factors has caused a number problems including:
• Operators overloaded with data and alarms;
• Non-intuitive interfaces requiring people to work harder to use the equipment;
• Replacing analogue panels with computer screens can reduce the amount of information visible to the operator at any one time and removes a degree of spatial awareness;
• Over-reliance on the technology because people assume a new machine is more sophisticated than it really is and so cannot get things wrong.
However, even when new technology is implemented well, it can have a significant impact on the people operating the system. This can be positive, by using automation to relieve people from boring, unpleasant and potentially hazardous tasks. Also, achieving more consistent operation and more reliable response to events and abnormal situations.
However, these can come at a cost, including:
• People end up working in smaller teams, and are more likely to feel isolated;
• The absence of one team member has a proportionally greater effect on either the team’s ability to deal with high work-load events or other team members work extra hours to cover the gaps;
• People have less autonomy because they are driven by what the equipment is doing;
• People have less opportunity to make positive contributions to the job;
• Operators have less opportunity to experience abnormal situations, and those situations can be more complex than is the case for manual operation;
• Managers reduce their interaction with their staff because they can access the data they need from their desk without having to visit the control room.
Managing the changes
There are many reasons why control rooms have changed. In some cases it has been because existing equipment has become obsolete. In others it has been perceived that new equipment has greater functionality or is more reliable. In many cases it is to reduce costs by using technology that is cheaper to maintain and reducing the number of operators required. In some cases the driver has been to improve safety by using technology that has more safeguards, or by moving control rooms away from hazardous areas.
Often there is more than one driver and/or other changes occur at the same time. This makes managing the changes difficult. To some companies a new control room is seen as a re-instrumentation project, and so run by instrument engineers. Others see it as a process improvement, and the project team includes more people with operations experience. Others recognise it as being, or at least including elements of organisational change, and so include more business management personnel. The reality is that implementing a new or upgraded control room is a complex project that involves the use of technology, but will impact greatly on people at multiple levels in an organisation.
Many companies fail to recognise the potential impact of a new or upgraded control room and so fail to adequately control the risks. Examples of problems experienced by companies include:
• Creating resistance to changes because people do not understand what is happening, cannot see the benefits or suspect ulterior motives that may impact on their employment and/or terms and conditions;
• Creating a high training load by simultaneously introducing new processes, control systems and ways of working;
• Failing to recognise the informal arrangements that make a positive contribution to operations, which are no longer possible because of the way system changes have been implemented;
• Limiting the options for covering sickness and holidays because teams have become smaller and individuals more specialised in their roles;
• Creating a system that requires a higher degree of skill than is available within the existing workforce.
RISKS FROM CONTROL ROOM OPERATIONS
Potential hazards
A hazard is something that has the potential to cause harm. Some hazards are easy to identify. Many of those associated with control room operations are not because their effects may be delayed or remote from the actions made by the operator.
For any occupational setting, the first hazards to consider are those in the proximity to where work is taking place. A control room is generally considered to be a reasonably safe place, similar to an office. This means the main concern would be slips, trips and falls. In addition, control rooms are likely to house some electrical equipment and maintenance within the building will inevitably involve some working at height. Clearly, most of these hazards should be avoided through good design, construction and maintenance of the building and equipment.
The second consideration is what does the person do that can cause them harm? For the control room operator excess physical exertion or exposure to hazardous agents is unlikely to be an issue. In fact the lack of physical activity may be more of a problem with the potential for back pain, repetitive strain injury and weight gain. More importantly, mental exertion may be an issue, with long periods of monotony and occasionally high demands resulting in stress and fatigue (with shift work likely to exacerbate this).
The third consideration is the hazards surrounding the control room that may affect its occupants. These would include flammable, explosive and toxic materials that may be in other parts of the building or outside.
The final consideration is the hazards that may or may not have the potential to affect the occupants of a control room, but are being controlled from the control room. The issue here is that the errors of the control room operator can affect many people including staff, neighbours and the general public. Although the risks to the control room operators may be modest, their actions and errors may create very great risks for others.
Risk assessment
Risk assessment is an accepted method for any workplace, and is equally applicable to a control room. It can address the normal hazards associated with the workplace. Specific methods can be used to assess risks associated with display screen equipment, fatigue and stress. Also, vulnerability to external events can be addressed by ‘occupied buildings’ assessments.
Whilst this is all applicable and worthwhile it does not address the potentially highest risks, which are associated with operational errors that are either initiated or allowed to escalate due to the errors made by control room operators. This is another reminder to us that a control room is not a system in its own right, but a component in large and complex system.
Assessment techniques
People often find it difficult to understand the process safety risks of control room operations, and struggle to assess them in an effective manner. This is because many are quite intangible. However, there are number of techniques freely available that have resulted from work carried out on behalf of the Health and Safety Executive that can assist by providing some structure to carrying out assessments in an objective manner.
HUMAN FACTORS ASPECTS OF REMOTE OPERATIONS OF PROCESS PLANT
This was published in 2002 as Contract Research Report CRR432. Although it does not describe an assessment methodology, it lists a number of issues to consider when evaluating a control room. These include
• Location – things to consider as control rooms are moved further from the system being operated;
• Communications – the impact of communication methods that do not include face-to-face interaction (e.g. radio, telephone, written);
• Interface – the differences between older panels and modern VDU displays;
• Automation – the benefits and risks of increased levels of automation;
• Team – the potential impacts of smaller teams and different organisations (e.g. self-managed teams);
The publication includes some checklists of issues that are useful for evaluating existing control rooms, and when considering changes to arrangements. These are useful for guiding ‘brain storming’ storming sessions and structuring risk assessments.
ASSESSING THE SAFETY OF STAFFING ARRANGEMENTS FOR PROCESS OPERATIONS IN THE CHEMICAL AND ALLIED INDUSTRIES
This was published in 2001 as Contract Research Report CRR348. It followed concerns from HSE that companies were reducing staffing levels and making other changes to staffing arrangements without adequate assessment of the risks. The HSE were concerned that these changes could impact on the ability to control abnormal and emergency conditions; and may also have a negative effect on staff performance through an impact on workload, fatigue, etc.
The publication presents a practical methodology that has been widely used. It has proved most effective at assessing control room arrangements. Subsequent guidance has recent been published by the Energy Institute.
Assessments are carried out during facilitated workshops, similar to HAZOP. The first part of the methodology assesses the likelihood that hazardous situations will be correctly detected and diagnosed by the control room operator, and that the appropriate response will be made. The second part assesses whether the organisation is place to ensure the arrangements are sustainable.
The methodology considers a wide range of issues, including staffing levels. However, it is emphasised that it does no calculate a minimum or optimum number of staff. Rather, it takes into account all relevant arrangements to conclude whether staffing, technical and/or organisational issues need to be improved. The methodology is particularly useful where arrangements are being changed.
The benefits of the using the method have been shown to include:
• It brings staffing issues into the open;
• It is practical, useable and intelligible;
• It is robust and resistant to manipulation and massaging of its output;
• Results in practical and effective improvements.
DIFFERENT TYPES OF SUPERVISION AND ITS IMPACT ON SAFETY IN THE CHEMICAL AND ALLIED INDUSTRY
This was published in 2004 as Research Report 292. It presents a thorough definition of what constitutes supervision as a management function and its impact on health and safety; and a method of assessing how supervision is delivered so that areas for improvement can be identified.
Although the method is not specifically related to control room operations, it is clear that in modern organisations the control room operator often fulfils some significant aspects of the supervision function. Also, the way a team functions has a significant impact on how well the system operates and the hazards are controlled. Therefore, supervision should be an important part of any assessment of control room risks.
MANAGING THE RISKS
Putting risk controls into practice
Control rooms do not just appear within our systems but occur as the result of significant projects. In many case these projects start with the aim of using the best available technology and following the latest design standards. Often, it is assumed that this approach will guarantee success. However, the failure to consider the impacts on the people that must operate from the control room combined with the inevitable constraints placed on projects by budgets and time can cause human factors problems.
Involving end users in the design process is an important step in managing the risks of control room operations. It provides the opportunity for the people who will operate from the control room to tell the designers what they need and want. It should definitely be considered as being a minimum requirement but does not, on its own address all the issues.
The techniques described above assist in assessing risks and suggesting controls by challenging experience and assumptions. They can be used to assess how well existing control rooms contribute to the management of process risks and encourage designers to consider systems beyond the control room. Also, they can encourage the end users to move beyond asking for the recreation of systems similar to those they have experience of and to accept changes that will result in reduced risks.
Issues requiring particular attention
Although control rooms and the systems they control vary a great deal, experience of assessing existing and new control rooms shows a number of recurring problems. Many of these have arisen because technological advances have been implemented without fully considering the impact. This is often because the human factors are not adequately considered. In each case, whilst the design of the control room can contribute to the risk, the solutions go far beyond physical design and enter the realms of management and organisation.
STRESS MANAGEMENT
Stress is a real hazard of control room operations, and as well as affecting the health of the individual, it can result in higher rates of error with potentially serious consequences. For many control room operators the greatest problems are due to boredom and frustration, which are often closely related to motivation. To avoid these problems people need to perceive that their work is meaningful and satisfying, which generally requires :
• Skill variety - the opportunity to use skills
• Task significance - a feeling that the work is worthwhile
• Task identity - having well defined tasks with specific objectives
• Autonomy - being able to control how work is performed
• Task feedback - receiving information that confirms work has been successful
Unfortunately the modern control room does not automatically fulfil these needs. For example, most of the control room operator’s job is to monitor automated systems, which gives little variety or autonomy. Also, the task is never ending, especially with continuous operations. This means individuals receive little direct feedback of how successful they have been and hence there is little identity with the outcomes. To some people this issue may be considered a trivial matter of job satisfaction. But if people are stressed it can have serious health consequences and, if it results in making more errors, then major accidents become more likely.
There is also the possibility of stress caused by high demand situations. Clearly, the best strategy is to avoid those situations in the first place. However, the design of the control room, human-machine interfaces and the supporting organisation can have significant impact on how well a control room operator can cope with events. Also, it is important to train people in emergency response, to assess their ability to cope, and to have systems in place to deal with after the event.
FATIGUE MANAGEMENT
Many control room operators will work shifts, which will undoubtedly raise concerns regarding fatigue. The working environment and nature of the tasks can increase the level of fatigue, which then increases the likelihood of error. Clearly the room needs to be designed to minimise the likelihood of fatigue through lighting and ventilation. Control room operators need the opportunity to take breaks away from their consoles, both on a regular basis and if they are feeling tired. However, as control rooms become more technical there is a tendency for people to become more specialised in their roles. Combined with the continual pressure to downsize teams, the ability for operators to take quality breaks is reducing. Also, it is important that the hours worked by operators are controlled. This is often not the case, with operators being able to work overtime and swap shifts without control or review.
COMMUNICATION
Communication has a key role in operators maintaining an up-to-date view of how their systems are functioning, and in the execution of tasks. Also, it will affect how well control room operators are able to detect, diagnose and coordinate the response to events.
As control rooms become more remote, there is less opportunity to communicate face-to-face and greater reliance on other means. Radios and phones are used more often, along with email and other less immediate forms of communication. As well as generally being less effective that face to face, there can be significant problems with reliability, and often there is no suitable backup available.
PROCEDURES
Procedures describe how tasks are (or should be) performed. In theory control room arrangements should not influence procedures directly. In practice the use of technology and automation does affect how tasks are performed, and potentially the frequency that someone performs a task. Also, there can be different modes of operation (e.g. automated and manual control) that will affect the role played by the human. Unfortunately many companies do not have good procedures and there can be cultural problems that affect their use. This can mean that procedures that may have been adequate in the past are no longer suitable for current ways of working. Development of procedures should be an important part of any control room project, but the procedures needed in the future may be quite different to those that have been used in the past.
TRAINING AND COMPETENCE
Even with the best procedures, control room operators need to be highly skilled and knowledgeable of the systems they operate. At present there is an over-reliance on on-the-job training, with insufficient structure. The result can be the passing on of poor practices and bad habits. Also, with highly automated and reliable systems, on-the-job training does not provide the opportunity to learn about the response to abnormal events. On-the-job training will always be a key part of learning a control room operator job but it is necessary to provide structure to ensure the correct skills and knowledge are achieved, to supplement it with various forms of simulation and to assess that appropriate competencies have been achieved.
The methods that people will become competent in control room operations needs to be considered as part of any control room project. This should cover both the immediate needs prior to commissioning the project and in the longer term. New technology may mean that some tasks will be performed differently and possibly much less often than in the past, which means training and methods of maintaining competence will need to change. Also, providing space and facilities to train people needs to be considered in the design.
SUPERVISION
Although control room arrangements do not directly affect supervision, they have resulted in smaller teams and hence a perception that less supervisors are required. In fact, as control room operators have required higher level skills they have tended to take on roles previously performed by supervisors, whilst all individuals on teams are tending to manage themselves to a greater extent.
The location of a control room can affect how a supervisor is able to perform their role. For example, if they have an office in the control room they may be more able to supervise the control room operator, but may be less able to monitor the activities of people working outside of the control room. Also, as control rooms have become more technical the operator job has become more specialised. This means it is now quite frequent for a supervisor to be in the position of supervising people in a job they cannot do themselves, which also limits the amount of support they can provide.
CONCLUSIONS
Control rooms perform many roles. They are a workplace, with all the hazards related to ‘normal’ jobs. They can act as a refuge providing protection against hazardous events, in some industries at least. And they are a component in a complex system where people and equipment come together to control that system.
The important thing to realise is that they are only a component and not a system in their own right. It is easy to become focussed on the physical arrangements and technology and forget that they are essentially a tool for the operators to help them do their job. Like any tool, they have to fulfil the needs of the user and the business. It is easy to assume that using the latest technology and following the latest design standard will generate a successful outcome, but this is only part of the picture.
The construction of a new or significant upgrade of an existing control room is invariably accompanied by other changes such as centralisation, de-manning, use of new technology and increased automation. Whilst the operator is often trained in detail about how the control system, which is likely to be new to him/her, is used the other aspects of change are often treated in much less detail or even completely over looked. This is usually because the fact that new control rooms can fundamentally change the way people communicate, teams function and the system is operated is often not appreciated or analysed in any detail. The reality is that in modern control rooms the operators have less opportunity to communicate face to face, they work in smaller teams with less supervision and their window on the system provided by computer monitors is significantly less than was provided in the past where analogue and schematic displays were the norm.
Involving end users in the design of a new control room or major upgrade can undoubtedly remind the design team that there is a human element to the control room. However, without any structured prompts this involvement can result in demands for a system that recreates many of the features of control rooms encountered in the past. Techniques are available that encourage challenge of past experiences; highlighting weaknesses that may have been overlooked or accepted because there had not been any major failures or accidents. They allow control room projects to become a process of improving risk management by addressing all technical and human aspects of a control room.
REFERENCES
Energy Institute 2002. Report of Workshop on Human Factors in the Petroleum Industry.
Energy Institute 2004. Safe Staffing Arrangements - Use Guide for CRR348/2001 Methodology
Hackman, JR and Oldman, GR 1980. Work Redesign.
HSE 2001. Assessing the safety of staffing arrangements for process operations in the chemical and allied industries. Contract Research Report 348/2001
HSE 2002. Human Factors aspects of remote operation in process plants. Contract Research Report 432/2002
HSE 2004. Different types of supervision and the impact on health and safety in the chemical and allied industries. Research Report 292
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