Typically in organizations that do not use best practices for maintenance planning and scheduling, direct utilization only reaches ∼ approximately 20-30%. Organizations using best practices may achieve world-class performance of 50%. Therefore, it is useful to divide the direct utilization percentage acquired from the LAA by the world-class target value of 50% to obtain a normalized factor for our productivity calculation.
The measurement of activity in terms of direct, delay and support elements provides an excellent approach to track and continually focus and prioritize efforts. Improvements in direct utilization can be targeted once the loss areas are measured to identify those areas needing the most attention. These elements can then be re-measured in subsequent LAAs to track improvement and assess the impact of planning and scheduling functions within the organization.
Frequently, initial work-sampling results show improvement opportunities that are easily realized through better maintenance planning. Furthermore, lowering the percentage of indirect activity directly translates to opportunities for increased work output, which often results in enhanced equipment reliability.
The percentage of actual direct time needed to perform a task versus the standard time for that task is direct productivity. The standard time represents how long an average skilled technician, working at normal pace, needs to perform a direct activity — using a prescribed method — without allowance for personal needs, fatigue and delays.
Time standards are common for most recurring tasks within operations. However, for purposes of maintenance craft calculations, standard times can best be determined as the expected time that was planned for the task. Therefore,
Direct Productivity = (Standard (Planned) Hours)/(Direct Hours) × 100%
A number of skill-improvement programs and motivational methods can be used to improve direct productivity. Such methods include specialized skills training, multi-crafting and multi-skilling of the workforce, modular designs for equipment removal and replacement, use of quick-disconnect fittings, special jig usage and pay-for-skills programs.
This is the amount of craft labor required to perform maintenance tasks a second time because of inadequate original work. Factors such as poor workmanship and use of the wrong materials or parts can mandate rework. Whatever the reason, rework reduces craft productivity and increases craft labor costs because time available for other activities is lost.
Conceptually, the effect of rework on overall productivity is easily understood but in practice rework can be a very difficult activity to measure. Usually it is only identified anecdotally during team discussions or planning meetings. However, for computational purposes rework can be fairly easily estimated if we assume that most repetitive maintenance tasks for the same equipment item over the course of a short time period (say, one month) stem from some error or omission by technicians. Given this assumption, rework can be estimated via a computerized maintenance management system (CMMS) report generator. The estimator can be calculated as follows:
Rework = (Total Craft Hours Other Than First Time for Each Piece of Equipment)/(Total Craft Hours in Period (month))
The measurement of rework can provide a focus for corrective actions. Losses can be categorized by cause, such as bad material, technician oversight, ineffective procedures, inadequate training, etc., and then corrective actions taken and their impact tracked. Typical corrective actions include assigning more-qualified personnel to certain tasks, developing job plans and procedures for repetitive work, adding equipment-specific training programs and identifying proper tools and equipment needed for tasks.
The overall calculation
With these structural elements and components defined, we now can combine our estimator for rework with our calculations for direct utilization and direct productivity to complete the calculation for overall craft productivity. Figure 2 summarizes the major elements of this calculation and common opportunities for improvement of each of the elements.
Most organizations do not measure many of these activities. However, those organizations that do the calculations and apply key corrective actions achieve top-quartile asset performance, and thus, significantly enhance their financial performance. Implementing the measures described in this paper should bolster productivity within your organization.
Timothy J. Finigan is Senior Director Performance Technology for Fluor, Greenville, S.C. E-mail him at Tim.Finigan@fluor.com.