10 key indicators of maintenance performance

- Mechanical availability (asset utilization) The "business contribution" of maintaining personnel is to provide highly reliable equipment at the lowest possible cost.
By Edwin K. Jones January 1, 1999

– Mechanical availability (asset utilization)

The “business contribution” of maintaining personnel is to provide highly reliable equipment at the lowest possible cost. World-class plants are typically driving reliability rather than cost reduction. (Industry sensitive)

– Ratio of direct maintenance personnel to support maintenance personnel

World-class plants tend to fall in the range of 2:1 to 3:1 workers per support person. Support personnel are those who provide the supervision, parts management, planning, reliability improvement, equipment condition monitoring, and other supporting tasks for the “hands on” workers.

Ratio of direct maintenance personnel to maintenance planning personnel

Ratio of direct maintenance personnel to engineering and technical maintenance personnel

There is usually a correlation between this metric and a plant’s equipment reliability and costs.

Maintenance cost as a percentage of plant estimated replacement value

This value is a classic measure of maintenance cost. Unfortunately, by itself, it drives cost reduction behavior without necessarily reinforcing the need for improved maintenance practices.

Ratio of plant estimated replacement value (in millions) to direct maintenance workers

This value is a measure of direct maintenance worker productivity (“How much plant and equipment,

in dollars, can each worker maintain?”). Many world-class plants fall into the range of $6-$9 million/worker. (Somewhat industry sensitive)

Maintenance contracting cost as a percentage of total maintenance cost

This value is a measure for comparison, but without a “target” value. World-class plants don’t shoot for a specific level; rather, they are disciplined in defining the role of contractors in maintenance, based

on business-related criteria. On average, top plants around the world contract over 30% of their maintenance work — a little less in the United States. But, top plants are driven by a defined

strategy, not a target percentage.

Stores parts and investment as a percentage of plant estimated replacement value

For years, the target for this measure was about 1%, but top plants around the world now routinely achieve ratios in the range of 0.25%-0.5%

Stores turnover (ratio of annual disbursements to inventory value)

This ratio reflects stocking strategy and may run above or below 1 depending on the plant’s strategy (for example, balancing risk against insurance stocks). Performance is measured against the plant’s own target.

Ratio of stores disbursements to stores personnel (dollar investment/stores person)

This value is a measure of “productivity” of the stores operation and associated personnel.