Preventive maintenance not getting done? Track your labor efficiency

By Tom Moriarty, P.E., CMRP, contributing editor Plant Services Magazine

My company recently has been working with an organization that was clearly not getting all of its preventive maintenance (PM) completed. When we pointed it out, the supervisors said, “We have too much to do and not enough people.”

The consequence of not getting PM done is that equipment becomes unreliable. Unreliable assets can disrupt a plant’s operations and lead to high-cost repairs (with expenses that soar thanks to overtime, expediting, etc). At the end of the day, the unit costs to produce are much higher.

In the scenario described above, among the “knowns” are the number of people and available work hours, the total annual required PM hours, the fact that all PMs are not getting done, and the fact that the people responsible for doing PMs believe they don’t have the resources needed to get them done.

What are the unknowns? First, we don’t know whether the number of people available can get all of the work done. Second, we don’t know whether the workforce on-hand is being efficiently utilized. Beyond that, we don’t know whether the PMs are the right types of tasks, and whether they are being done on the right assets at the right frequency. We’ll assume for the time being that the PMs are correct in type and frequency.

Let’s start with the basics. Are there enough people to get the PMs done?

Assume for the moment that a well-functioning maintenance organization should be allocating somewhere around 35 percent to 40 percent of its available hours doing PM-type work. PM work includes time-based tasks as well as condition-monitoring tasks – not corrective maintenance, admin or training time. Assume there are 30 workers on the maintenance team. If each worker is available for 1,950 hours per year, then there are 58,500 total hours per year available. So, the theoretical labor hours that should be allocated to PM would be between 20,475 hours (35 percent) and 23,400 hours (40 percent) per year.

Compare the theoretical annual amount of PM labor with the total annual PM hours currently specified. If the annual total PM hours specified were 30,000, there would not be sufficient resources to complete the PMs. On the other hand, if the annual total PM hours specified were 15,000, there should be no problem getting all the PMs done.

Suppose the organization has sufficient labor available but it is not getting the PMs completed.  What’s the problem? In cases where there are enough resources to get the work done but it isn’t happening, the problem is most often related labor efficiency.

How do you measure labor efficiency?  This can be done by performing a barrier survey to identify the things that get in the way of workforce members doing their jobs.

How do you do a barrier survey?

Over a period of between several days and a few weeks, randomly attach yourself to a work order. When work orders are handed out, pick one and follow the person to whom it was assigned. Track at least a dozen work orders and as many people as you can. Write down the time this person spends on categorized activities. Categorize each block of time as time spent working on an asset; traveling to/from a job site; waiting for tools, parts, instruction, or permits; or waiting for authorization to proceed with the work. Create six to eight categories that best describe the time allocations.

Calculate approximate percentages of time spent in each category. For typical reactive maintenance organizations, you’ll find the hands-on time (wrench time) to be less than 30%. If work is being planned and scheduled at a reasonable level, you should see values around 45%. If your maintenance organization is doing really well, you should see values above 50%.

Unless or until you investigate further, don’t accept a contention that your workers have too much to do and not enough resources to do it. Similarly, at the other end of the spectrum, never assume that your workforce is idle. The best thing to do is objectively look for evidence and then formulate a plan to improve the situation.

Read Tom Moriarty’s monthly column, Human Capital.