The third principle of scheduling is that the advance maintenance schedule should be crafted for a week. The weeklong time frame is the best for maximizing productivity through goal-setting. This schedule consists largely of a simple listing or “batch” of work orders that doesn’t specify particular days for the work for the upcoming week. It’s important to note that the proposed schedule must be acceptable to both the maintenance supervisor and the operations leader for the area.
There are different schedules in maintenance; each has its appropriate purpose and application. The yearly maintenance schedule is about the budget. How much does the plant anticipate spending, and how much has the plant spent already? The monthly maintenance schedule is largely about PMs. Is the plant keeping up with preventive maintenance? The daily maintenance schedule is about assigning individual craftspersons and coordinating equipment clearance and lockout/tagout (LOTO). It’s the weekly maintenance schedule that plants understand the least, so it provides the greatest opportunity for maintenance improvement. The weekly schedule is about productivity.
The weekly time frame is the right horizon for goal-setting. First, the week is long enough to “smooth out” the wide variance of individual labor estimates. Individual time estimates may be wildly inaccurate, but when taken together, they present a very normal distribution. In other words, while an individual work order estimate might not be very accurate – with a time variance of, say, +/- 100% – a week’s worth of work for a crew will tend to have great accuracy (say, +/-15%) One might ask whether planners should provide more-accurate labor estimates, but maintenance is simply not assembly-line or automobile-shop work where there are enough repetitions to develop repeatability. Fortunately, the productivity objective does not require great accuracy of individual estimates.
This weekly time frame also is long enough to provide a critical service for the maintenance supervisor: It allows for backlog research. Most plants neglect the less-urgent work in their backlog to a fault. The scheduler looking at an entire week can research the backlog to match up such less-urgent work with the more-urgent work that will be scheduled anyway. Matching up work for convenience is a great efficiency benefit to help maintenance crews find work in the same systems or area and to help operations combine LOTO. Even more important, the extra found work is usually proactive.
Another critical feature of this weeklong frame: It’s short enough to protect, which is an important aspect of goal-setting. A goal should be RUMBA: Reasonable, Understandable, Measurable, Believable, and Achievable. It is reasonable for the maintenance crew to try to protect a week’s worth of work from interruption by asking operations whether new work can wait until next week. Operations might agree to wait a week, but asking the team to wait a month generally is not reasonable. The churn of daily maintenance, on the other hand, prevents the daily schedule from being the starting point for goal-setting. Jobs are continually running past their allotted time or finishing sooner than expected.
With the weekly schedule, there are some “hard” elements, such as particular work order that must be done on a Wednesday or an appointment to assist a contractor on a Thursday, but the schedule otherwise reflects a batch of work that could be coordinated with operations for LOTO as the week unfolds and completed by maintenance. To be clear: The weekly schedule is not five daily schedules pushed together and called a weekly schedule. Such advance daily schedules would have to be revised each day; this would run counter to our productivity goals. Plants seem to focus so much on formally moving jobs from day to day that they lose the sense of completing the week’s worth of work.
Finally, the proposed weekly schedule must be acceptable to maintenance supervisors and operations leaders. The backlog research that supports this schedule should promote reliability as well as convenience of maintenance execution and operations LOTO. When the weekly schedule is properly created, maintenance and operations should accept it.
The weeklong time frame is the right one for targeting improvements in maintenance productivity, and the best weekly schedule is simply a batch of work that provides a goal.