The Controversy of Fully Loading the Weekly Schedule 100 Per Cent
BY: Doc Palmer
TIP: Don’t schedule fewer hours to allow for reactive work. Instead schedule more hours and allow breaking the schedule for reactive work.
Perhaps the greatest controversy of maintenance scheduling is loading the weekly schedule to 100 per cent of the forecasted labour capacity. Fully loading the schedule intuitively seems wrong because most plants have a significant amount of reactive maintenance. But not loading the weekly maintenance schedule to 100 per cent not only fails to give the huge gain in productivity, but also makes scheduling into a counterproductive activity. Not only does it not add value, it decreases value. In this manner, most plants only schedule about 70 per cent of their labour capacity, if they schedule weekly at all, and many of their weekly schedules are too complicated.
Purpose of the Weekly Schedule
The purpose of the weekly schedule is to increase productivity. Studies typically show normal maintenance productivity to be only about 35 per cent in terms of wrench time. This same level of 35 per cent wrench time is found everywhere because it is a human issue, and, of course, plants everywhere staff maintenance with humans. At 35 per cent wrench time, humans “feel busy.” In practice, if a plant’s backlog is growing too fast and everyone is “busy,” management hires more labour. However, whenever someone leaves the workforce, management waits until the backlog is again growing too fast before they will hire a replacement. This practice is called “backlog management.”
Furthermore, since engineering and operations realize that the maintenance force is busy, they are reluctant to add too many proactive tasks or little problems (they know about), to the backlog. Consequently, the company has a system that actually locks in place merely “normal” productivity. Nevertheless, a superior 55 per cent wrench time productivity is easily achievable and sustainable through 100 per cent fully loaded schedules. The extra wrench time gives a workforce a 57 per cent bump in its work order completion rate (shown by 55 per cent divided by 35 per cent equals 1.57).
That means that a workforce completing 1,000 work orders per month will suddenly start completing 1,570 work orders per month. Therefore, the purpose of weekly scheduling is to take advantage of this opportunity to increase productivity. Unfortunately, most plants act like the purpose of the weekly schedule is to “complete the weekly schedule.” Wanting high schedule compliance scores and not wanting to “set themselves up for failure,” they schedule about 70 per cent of the labour forecast. They reason that this practice allows for the typical 30 per cent reactive work and some unscheduled employee absences.
For example, for 400 hours of labour available, they would only schedule 280 hours’ worth of work. And then completing over 251 hours of that work would give a schedule compliance score of over 90 per cent. Unfortunately, these plants have only 35 per cent wrench time. They have missed the whole point of scheduling. They do not have 55 per cent wrench time because of Parkinson’s Law, which states, “The amount of work assigned will expand to fill the time available.” (Cyril Parkinson. 1955. Parkinson’s Law. The Economist, November 19, 1955.) This law means that if a schedule does not include enough work, the work included will take more time than it should.
In practice, maintenance crews given schedules that only fill 70 per cent of the available labour hours are destined to complete less work than they otherwise might.
In contrast, plants that fully load crews with 100 per cent of the forecasted available labour and also freely allow them to break the schedule, do better. They routinely achieve a much higher productivity shown by a much higher work order completion rate. Fully loaded schedules defeat Parkinson’s Law, but only by expecting schedule compliance below 90 per cent.
In other words, don’t schedule fewer hours to allow for reactive work. Instead, schedule more hours and allow breaking the schedule for reactive work. By allowing schedule breaks, crews accept the fully loaded schedules as a realistic “mission” that drives the higher productivity. Without a sense of mission for regular maintenance, crews inappropriately adopt a culture of “taking care of operations and keeping everyone busy.” And the point of “feeling busy” is only 35 per cent. Another improper practice is not having a weekly schedule at all. These plants simply let supervisors assign work to take care of operations and otherwise keep everyone busy. This practice gives only 35 per cent.
Another practice that becomes counterproductive is when plants make weekly schedules too complicated. Many plants, wanting a “perfect” schedule and to set expectations, create five daily schedules a week ahead of time and then the weekly schedule. Often this schedule has work assigned to individuals, with specific hour slots. Real-life maintenance has too much churn to set such daily schedules a week in advance. As a result, these plants make supervisors revise the entire rest of the week schedule at the end of every single day. This wasted time is counterproductive in itself; it also further encourages schedulers not to schedule too much work, so less work will constantly move around.
Instead, the weekly schedule should be mostly a simple batch of work from the backlog that forms a mission. It is also mostly a “soft” schedule with only a few “hard” dates and times for certain work orders for the upcoming week.
Be effective with weekly schedules by recognizing their true purpose to increase productivity. Avoid the subtle trap of thinking you are making a schedule that can be completed. MRO
Doc Palmer, PE, MBA, CMRP is the author of McGraw-Hill’s Maintenance Planning and Scheduling Handbook, and as managing partner of Richard Palmer and Associates helps companies worldwide with planning and scheduling success. For more information, including a schedule of current public workshops, go to www.palmerplanning.com or e-mail Doc at email@example.com.