Managing pending work in the backlog

The definition of the backlog

The backlog consists of all identified and validated work that is awaiting completion.

Managing and controlling the backlog

An effective backlog management process is crucial for keeping it under control. The first step in maintaining a healthy backlog is systematically reviewing and approving new work requests.

A best practice is to implement and consistently hold a daily review meeting with the natural work team, which plays a key role in managing backlog entries. This team typically includes the maintenance planner, maintenance supervisor, and production coordinator/supervisor.

Each day, they should assess all new work requests submitted within the last 24 hours (or the last 72 hours on Monday mornings).

During this 10- to 15-minute daily meeting, the team should address the following questions:

• What is the purpose of the request?
• Is it truly necessary? If so, what is its priority level?
• Which trade will be responsible for the work?
• What is the estimated time required to complete it?
• Is it a modification? If so, it must go through the modification approval process before being added to the backlog.

Any unclear or incomplete requests will be sent back to the requester for clarification. If a request is deemed unjustified and rejected, the requester must be informed of the reason for the refusal.

The second critical aspect of backlog control is the planner’s regular review and selection of work orders to develop the weekly work schedule. Effective backlog management requires consistency and discipline, ensuring that prioritization is not based solely on the “flavor of the week” while overlooking tasks that have been pending for weeks or even months.

As a consultant, I often encounter situations where the production or maintenance team creates new work orders simply because existing requests in the backlog have been forgotten or overlooked. This leads to a cycle where urgent issues take priority, while the backlog remains outdated and unmanaged.

As a result, work orders accumulate without being addressed in time. What initially starts as a routine task eventually turns into an emergency, as equipment conditions deteriorate, potentially leading to functional failure or complete breakdown.

Calculating the backlog

Backlog calculation should not be based on simply counting open work orders. Instead, it should be measured in terms of total pending work hours, which can then be translated into the number of backlog weeks.

For this calculation to be accurate and meaningful, each work order must include an estimated duration. Tracking backlog in this way allows the management team to evaluate the maintenance department’s capacity to complete scheduled work within a reasonable timeframe, ensuring plant operations are not compromised.

How is backlog measured in weeks?

The formula for backlog calculation is straightforward:

1. Should Preventive Maintenance Be Included in Backlog Calculation?

No. Preventive maintenance tasks should be managed separately, with the required workforce deducted from available capacity. Similarly, hours dedicated to projects or planned shutdowns can be excluded and tracked as a distinct backlog category.

2. Accounting for Workforce Availability

To ensure an accurate backlog calculation, workforce availability must consider absences such as vacations, holidays, sick leave, and emergency work.

3. Practical Example of Backlog Calculation:

• Total estimated hours of pending work orders: 1,500 hours
• Maintenance team members: 12
• Weekly hours per employee: 40 hours
• Annual vacation hours per employee: 120 hours
• Annual holiday hours per employee: 72 hours
• Annual preventive maintenance hours: 6,000 hours
• Average emergency work percentage: 15%

By consistently measuring backlog in weeks, organizations can track trends over time and take corrective actions if the backlog grows or decreases significantly.

Recommended backlog levels and management strategies

A total backlog of 4 to 6 weeks is generally ideal. A backlog significantly larger than this may indicate a shift toward reactive maintenance, while a smaller backlog can lead to inefficiencies.

1. Consequences of an Oversized Backlog:

• Becomes difficult to manage.
• Encourage unnecessary urgencies.
• Increases spare parts reservations and replenishments.
• Early-detected issues may escalate into functional failures.
• Operations lose confidence in maintenance’s ability to complete tasks on time.

2. Consequences of a Small Backlog:

• Difficulties in assigning high-priority work.
• Increased unplanned work and schedule disruptions.

Backlog review process

A structured backlog review helps maintain efficiency. One of the best practices is sorting work orders by age and scheduling regular formal reviews with the natural work team (planner, supervisor, and production representative).

Key questions during backlog reviews:

• Has the work already been completed?
• Is the work still necessary?
• Does the priority level remain unchanged?

Since production owns the equipment, it shares responsibility for addressing these questions.

Further learning opportunity

For a deeper understanding of backlog management and maintenance planning and scheduling, consider enrolling in the Maintenance Planning and Scheduling course. This two-day training session will enhance your skills in this field.

Michel Emond, P.Eng.
Reliability Consultant – Laurentide Controls
[email protected]