Shift-Handover: 5% of Operations Time, 40% of Incidents

Shift handover series:

Part 1: Shift-Handover: 5% of Operations Time, 40% of Incidents

Part 2: Structured Logbook Design


A company in the oil industry found that whilst startup, shutdown, and changeover periods account for less than 5% of operations staff time, 40% of plant incidents occur during this time (NPRA 2009 National Safety Conference). In fact, every 2nd incident or accident in the process industry is related to communication errors that occurred during shift handovers.

When equipment needs to change operating mode, this gives way to a rise in risk - when operations staff change over to a new shift, the potential knowledge-gaps that result from the change give rise to risk as well. Ensuring that shift handovers are conducted in a clear and concise manner is one of the most important components in mitigating risk during periods of change.

Poorly written notes and/or technical misunderstandings are the root cause to these major issues. In this series we will look at some of the steps that we, as an industry, can take to move forward in improving the 5% to 40% figure. I believe that substantial improvements can be made by following these simple steps. Isn't this something that we can work towards together?

Effective Knowledge Transfer

Shift handover is effectively the transfer of knowledge from the outgoing staff member to an incoming staff member; typically thought to be a unidirectional process in which the outgoing operator decides which information is of importance for transferring, so that the incoming staff can effectively operate the facility.

Whilst it may seem reasonable for shift handover to be conducted in a unidirectional nature, research from Ronald Lardner (The Kiel Centre, 1999) shows that when communications are conducted in a bi-directional or repetitive nature (questioning, validating and repeating each handover item), the confidence and accuracy of the transferred knowledge is substantially improved.

The reasoning behind bi-directional communication during shift handover and why it shows improvement is that it creates alignment in the “Mental Model” of both operators. By aligning their mental understanding, the gaps in overall understanding are closed. In having a common understanding, there is less room for information to fall through the cracks.

I would like to start this series by focusing on Mental Modelling; what it is and its impact on shift handover. This approach is meant to explore ways that we, as administrators, can leverage the knowledge of our mental model (as well as our colleagues') for plant safety and overall improvement.

In subsequent articles we will look into the ways of properly structuring shift handover reports, and conclude the series by looking at the best practices for shift handover from the perspective of regulatory inspectors.

What are Mental Models?

Mental Models are defined as the organized models or structures of reality that enable us to understand, reason and/or interpret events. Philip N. Johnson describes Mental Models from an industrial perspective as:

“Organized knowledge structures that operators develop to understand and explain their experiences representing a specific task or knowledge domain.” (Johnson 2001)

In other words, a typical refinery operator will have his/her personal Mental Model for their respective process unit; based on their unique and personal experiences spanning over several years. A persons mental model is constantly evolving. Each and every time an operator speaks with colleagues or takes action at the facility, this is enhancing, adjusting and updating the operators mental model.

How are Mental Models Developed?

According to Yin and Laberge 2010:

“(Operators) do not blindly follow a sequence of instructions, but rather visualize the current process flow and initiate systematic actions in close consultation with field operators, while monitoring the reaction of the process towards achieving the desired state.”

So, operations staff do not just follow the instructions blindly; they read what to do, consider the impact according to their personal mental model, and the mental model of the field operators, then take the appropriate action in consulting with their peers.

The Yin and Laberge study confirmed that the operator’s mental model largely comes from the time they've working as field operators. Specifically, they identified the following key areas in field-based learning that formed the basis of mental modeling for most people:

  • Walking through the process to gain line-up and layout knowledge
  • Educational programs to learn how the process works internally
  • Where and why equipment is in a certain location
  • What happens in each component
  • Educating themselves on standard operating procedures

But, of utmost and critical importance was their personal experience handling incidents and upsets. What happened, why it happened, the process reactions, and how they were able to bring the process back to expected conditions.

We see this in other research that compared performance of junior and senior operators as well. The results have shown that junior operators whom constantly adjusted the control parameters achieved the lowest operations performance, whereas a senior operations group took few actions and achieved very high results.

This is expected to be the result of a highly developed and detailed mental model, which can clearly predict the result of any actions taken in the process.

Why are Mental Models imperfect?

It's simple: a standardized training course does not result in standardized knowledge. Each operator joins a company and facility with a personal background (e.g. working experience from other facilities). Even if two operators share experience from the same facility, their experiential learning is most certainly different. It is the difference in experiencing various incidents or excursions that result in developing “Mental Models” that are vastly different.


When operators write shift handover reports, the reports are based on one assumption - one BIG assumption! The assumed fact is that all staff members have a shared thought process and common understanding, that is, in line with their personal “Mental Model.” Herein lies the problem - this assumption leads to miscommunication, lack of a common understanding, and potential incidents.

Mental models are a key component of the decision making process. We have ZERO ability for 100% standardization, so, we are left in a rather ambiguous and challenging situation, aren't we?

How Does This Impact Shift Handover?

As mentioned in the introduction, we've seen that shift handover is one of the highest risk periods in facility operations and that the outgoing operator decides himself/herself on what is important enough to be passed to the incoming operator. But, critically, we know that what he/she decides is based on their personal mental model.

But what happens when the mental model of the incoming and outgoing operators do not align…?

Yin and Laberge (2010) rightly identified that even in the space of 12 hours, the facility can undergo significant change:

“As equipment conditions change during a shift, operators returning back to work after a 12 hour period of rest may find that the process units are now operating in a vastly different operating mode.”

Of course all operators will advise the incoming shift at handover if they changed the operating mode -- but, will they explain that when changing the operating mode they followed an "alternative" startup procedure (a procedure they deemed to be more efficient based on their own mental model)??

If the outgoing operators choose not to share this information, it is (most likely) because it may be assumed or 'a given' in their minds, based on their personal mental model and it's within the boundaries of the formal SOP. But the fact is, the startup procedure that the outgoing shift followed may be seen as an alternative procedure by the incoming shift

In other words, the outgoing shift will perceive this method as “standard” enough to be embedded in their mental model and not important to include in the shift handover, while the reality is that the incoming shift have been left in the dark. These small lacks in mutual understanding can lead to large disruptions down the line.

Bi-Directional Shift Handover

Whilst the risks in miscommunication are significant, the resolution is quite simple…Clear, Concise, Person-to-Person communications. But, putting this into practice day-in and day-out is where the challenge lies.


An operator’s role often alternates between periods of quiet and periods of intense activity, and in many cases work 12-hour shifts resulting in mental fatigue by the time their shift is completed.

From the perspective of the outgoing shift, the challenge in overcoming the disparity in mental models is expected to reside in 2 key areas, and require more clarity. They are:

  1. Timing of when key information occurs
  2. Mental fatigue at handover / report creation time

Often times, the information that is of most importance for safe and efficient shift-handovers occur during the periods of intense activity. As a result the operator typically takes notes in short-form and with minimal effort. The operator will sometimes deliberately exclude information because it is deeply embedded in his/her mental model. This excluded information would be considered normal or a standard result of a previously noted action - by the operator who wrote it down.

When handover reports are left unwritten until the end of shift, in many cases the key challenge is for the operator to then remember the fine details that occurred up to 6-12 hours prior.

Based on the above information, it is critically important for operators to see that the creation of shift-handover reports must be an ongoing process that begins from the start of their shift. The reports are to be periodically and critically reread from the perspective of a junior operator, ensuring a final report that is crystal clear.

Verbal Communication

The second component for effective shift handover is human-to-human interaction: both incoming and outgoing operators should review the full shift handover report together as a team - interpersonal communication is the key.

In particular, the following process should be conducted for each item in the shift handover report:

  1. Outgoing operator: Describe the entry
  2. Incoming operator: Ask any and all pertinent questions
  3. Incoming operator: Describe the results he would expect
  4. Outgoing operator: Confirm or Correct expected results

By communicating these four steps in each shift handover, for every entry, there are multiple checking stages. These stages assist to ensure that the knowledge has been mapped and recorded correctly, and in a sense compares the mental model of the incoming and outgoing operators - validating logic and avoiding technical misunderstanding.


Whilst there are some shining examples of best-practice, as an industry we still have large areas for improvement when it comes to shift handover. From both the vendor and users perspective, we must continue to find methods and technologies that enable operators to take notes during their shift - accurately, easily, clearly and concisely - whilst having minimal impact on the operator’s task at hand.

Most importantly, we must strive to create corporate cultures that promotes questioning. Ensuring that all staff are willing and able to question their colleagues on any matter, for the benefit and safety of the company, is vital, and will continue to be vital in the future as the industry becomes more competitive. Particularly when it comes to shift handover, all staff must be willing and able to question even the most highly regarded and respected staff to ensure a safe and stable environment.

Based on our knowledge and industry research, at Yokogawa we are working strongly across various industries in the area of shift handovers and shift handover reporting to support our customers in realizing industry best practices.

In the spirit of Co-Innovation we have been steadily building and enhancing our Real-Time Production Organizer – Logbook, Work Instruction and Shift Handover modules to realize this vision.

Do you have any questions or comments? Send us an email or leave a comment below!