Controlling Your Maintenance Turnaround Scope, from Kick-Off to Closeout

Article by Gordon Lawrence CEng FIChemE

Gordon Lawrence discusses the need to keep scope to a manageable size and avoid excessive scope growth.

THIS article is the sixth and final article in a series discussing various aspects of maintenance turnaround preparations. This one discusses the need to keep scope to a manageable size and avoid excessive scope growth. It points out that although many teams focus on freezing the scope and on challenging the scope (ie challenging whether individual scope items need to be included) just prior to scope freeze, in fact there are several other points during the planning and preparation phase when scope control measures can be implemented. These other points are often not as well addressed as the scope challenge. But those turnaround teams that do address them are setting themselves up to be in better control of their scope and hence better control of cost and schedule.

Maintenance turnarounds (sometimes called shutdowns or outages) are significant events in the long-range plan of any refinery, petrochemical plant, offshore production asset or other facility that uses large, continuous production process plant. They consume a lot of time, money and resources and they represent a considerable lost production opportunity while the facility is shut down for this essential maintenance, inspection and cleaning work.

Why keep scope under control?


It is common sense to recognise that the larger the scope of a turnaround, the more work needs to be carried out and hence the higher the overall cost that needs to be spent and the longer the plant needs to be shut down. Hence, it makes sense to keep the scope of any turnaround as small as possible in order to keep total cost down and to keep the time that the plant is shut down and not producing to a minimum.

In addition, several sources1 have noted the point that turnarounds can become too big for the organisation and infrastructure of a site to cope with. Hence, it’s important for each site organisation to be aware of what the upper size limit is for their site, when developing the plans for a turnaround.

It is also a known fact that the larger and more complex a turnaround event becomes, the higher the risk of cost and schedule overrun. In fact, the benchmarking firm, AP-Networks has documented this phenomenon2, showing an increase in average cost overrun of up to 20% and schedule overrun of around 30% for high complexity projects. Hence this is another reason to limit the overall size of any turnaround event to only the work that needs to be done.


What is perhaps less well recognised is that scope added to an event after scope freeze also increases the risk of cost and schedule overrun. Again, AP-Networks has documented this phenomenon3, showing that the average cost and schedule overrun increases with increasing scope growth. The probable cause of this increase in likelihood of cost and schedule overrun is the confusion, rework and late work caused by the late addition (or even removal) of new scope.

Some late scope is inevitable. There will always be “emerging” scope, as items of equipment unexpectedly break down between scope freeze and the start of the turnaround and there will frequently be “discovery” scope, the additional repair scope that is “discovered” as equipment items are opened for inspection during the turnaround. As noted in a previous study4, on very large downstream/onshore turnarounds, the average growth in scope (as a percentage of direct labour and material cost), combining both emerging and discovery scope is 23%. Top quartile performers manage to get this down to an average of 8%. But getting much below this level is likely to be unrealistic. Nevertheless, it is important to control and limit late scope changes if one wishes to control the risk engendered by those late changes.

Controlling the scope

In the previous section we have outlined why it is important to try to keep the scope of your turnaround as small as possible, by only doing the scope that needs to be done. We also outlined why it is important to minimise scope growth once you have developed the worklist and frozen the base scope. In this section we now discuss how one can achieve those two aims.

Most turnaround teams will recognise the value of a scope challenge, after the worklist of the base scope has been collated and just before freezing the scope. Most teams also recognise the value of having some form of change control procedure in place. However, few turnaround teams look at the entire preparation and planning timeline to consider all the activities that can be done to keep control of scope.

In fact, there are several points along the planning and preparation timeline, over and above the scope challenge and the initiation of scope control processes, where positive action can be taken to control scope. Below we discuss each of these points:

  • Setting the turnaround event up for success at the turnaround preparation kick-off, via the premise.
  • Effective scope gathering prior to scope freeze.
  • The scope challenge and scope freeze at around 12 months (depending on turnaround size) before the turnaround.
  • Change control for emerging scope leading up to the execution period.
  • Change control for discovery scope during the turnaround execution window.
  • The vital role of the steering team throughout the preparation and execution of the turnaround.


As was described in an earlier article in this series, most turnaround teams do not use the turnaround premise document to their advantage. They fail to ensure that the premise includes a clear statement of what the end state of the asset should be at the close of the turnaround and they fail to ensure that detailed scope selection criteria are documented in the premise.

But if the premise is used to its full effect, this sets clear and prescriptive rules for what can, and more importantly cannot, be included in the turnaround work list. This immediately sets a clear boundary for scope inclusion and is the first line of defence to limit the size of the event.


Turnaround teams often fall victim to a scope gathering phase that is ineffective, because operations, maintenance, process engineering and other staff do not give this phase sufficient attention. The upshot is that scope is “forgotten” and suddenly appears as “emerging” scope after scope freeze, instead of before scope freeze.

There are a number of best practices that sites can adopt to ensure that the scope gathering process is effective. These include:

  • Clear messaging from the turnaround team about scope inclusion criteria, and about deadlines for submitting scope, and about hurdles for late scope.
  • Clear requirements for a minimum level of detail to be provided in the worklist.
  • Site-wide messages from senior leadership, to remind departments to submit their scope.
  • Early and thorough review of maintenance lists (eg in SAP) to ensure that logged requests are tagged correctly for needing or not needing a turnaround.
  • Monitoring of each department, to ensure that there are no laggards in submitting scope.


Many sites now recognise the need for a scope challenge. But most still carry out the challenge in an ad-hoc manner, without external facilitation. The upshot from such ad-hoc challenges is frequently that instead of focusing on the “necessary” scope, it is the scope of whoever shouts the loudest and longest that is retained. This leads to an atmosphere of focus on “preferred”, as well as “necessary” scope, which in turn leads to grossly inflated work lists.

A good scope challenge5 will start from the scope criteria laid out in the premise and focus on:

  • Event-specific scope selection criteria – ie criteria to assess whether the scope item advances the business objective of the event.
  • Site-specific scope selection criteria – ie criteria to assess whether the scope item needs to be done in the event window, or could be done in routine maintenance, or achieved with a smaller, simpler scope.
  • Risk-based challenge – ie whether the benefit of doing preventive scope in the turnaround outweighs the risk of possible failure during the next production run.

When facilitating such scope challenges, we have frequently been able to challenge out around 30% of the challenged scope.


After the base scope work list has been frozen, any additional scope that “emerges” between the freeze date and the start of the turnaround event needs to be logged and challenged via an additional work request (AWR) system, to assess whether it is justified in being added to the work list. If this challenge process is not at least as rigorous as the general challenge that took place before scope freeze, it becomes too easy for scope to creep in.

There are a number of actions that can be taken, to ensure that the AWR process works effectively. These include:

  • Requiring the requestor to justify how this scope item meets the scope selection criteria laid out in the Premise.
  • Requiring the requestor to explain why this scope was not included prior to scope freeze.
  • Having a gradually increasing hurdle rate for request approvals, such that as the turnaround approaches, the requestor has to approach more and more senior staff to have the request approved.


There also needs to be an AWR process for scope that is “discovered” during the turnaround event. There are several common issues with the way that discovery AWRs are dealt with. One key issue relates to how the scope is approved. In the interests of timely decision making, the scope request often goes through a foreshortened AWR procedure and too often, a harassed turnaround manager is pressured to approve scope in a hurry. This is an easy loophole for operations to push through preferred scope that was previously challenged out.

A better system involves retaining the scope challenge process that was used earlier, with a dedicated squad to review AWRs in a rapid manner. This helps ensure that scope is not allowed through that has already been challenged out and ensures that only scope which meets the scope inclusion criteria is included.


The event steering team has a crucial role in “setting the tone” of focusing on only “necessary” scope. This role starts with the premise and goes through to the AWRs.

Firstly, steering team members need to be fully aware of the increased risk of a larger scope. They then need to be heavily involved in setting the scope selection criteria in the premise and with enforcing those criteria during scope gather and scope freeze. Their active involvement can be encouraged by requiring each steering team member to approve scope before it’s submitted to the work list.

In addition, steering team members also need to be aware of the need to minimise late scope, because of the heightened risk that late scope gives to the turnaround event. Steering team members need to accept responsibility for scope growth and its effect of cost and schedule predictability. They should not leave this responsibility to the turnaround team.


Turnaround teams and their steering teams should think about how to control scope throughout the life cycle of planning and preparation, not merely during the scope challenge and freeze. By following these six actions, the site can greatly increase their chances of keeping scope under control:

  1. Ensure the premise document defines clear strategic objectives for the unit after the turnaround has finished and includes prescriptive scope selection criteria based on those strategic objectives.
  2. Ensure that everyone understands the scope selection criteria and is focused on the target dates for gathering scope. Verify that all groups are working on gathering scope and will be finished by the target date.
  3. Use external facilitation for your scope challenge to avoid undue influence from vested interests.
  4. Use the steering team to enforce strong change control on emerging scope AWRs.
  5. Set up a rapid reaction team to enforce rigor in the scope challenge for discovery scope AWRs.
  6. Ensure that every member of the steering team is aligned on the need to focus on only “necessary” scope and on the need to minimise late scope. Ensure the steering team is active in their enforcement of this.


1. With credit due to my colleague, Frank Engli, Senior Consultant for Turnarounds & Maintenance at Becht Canada, some example rules of thumb used include (1) limits on the number of direct field labour workers per square metre of asset plot size; (2) a maximum multiple of the normal workday workforce on site during a turnaround; (3) the ratio of owner’s supervision staff to direct field labour workers.
2. Vichich, RP, Turnaround Excellence – Key Success Factors; 2012 AIChE Spring National Meeting, Houston,
3. Shirley, P; Turnaround Excellence Through Organizational Transformation, 2012 AFPM Reliability and Maintenance Conference,
4. Lawrence, GR; C minus, Room for Improvement – Improving Offshore Maintenance Turnarounds in the UK North Sea; Offshore Engineer, August 2017, pp38–40.
5. One example of an externally-facilitated scope challenge is given here:

Article by Gordon Lawrence CEng FIChemE

Regional Manager for Turnaround and Project Assurance at Becht

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