Owners and managers of pharmaceutical manufacturing properties have always faced challenges in keeping facilities current. But the pace of facility depreciation has heightened in recent years due to factors such as a shift toward the production of biological products, changes in manufacturing technologies to single-use equipment and greater use of automation. 

Proper maintenance is key to maximizing the value of these facilities. Over-maintaining a facility provides maximum reliability, but it comes with a cost, while under-maintaining it yields cost savings but long-term reliability problems. The key is to find a sweet spot in the middle. 

The 6:1 Ratio for Maintenance 

This dilemma was studied in 1997 by John Day, a plant manager at Alumax (later acquired by Alcoa). He found the ideal ratio of preventive maintenance to corrective maintenance (PM:CM) is 6:1. If you have more PM work requests you are over-maintaining the facility, but if you have fewer PM work requests you are managing more reactive work requests. 

CM work is always more expensive than PM work because it is unplanned and frequently takes away from production time, whereas PM work can be planned in advance. CM work also incurs investigation costs (Why did this failure occur? Was the product impacted? Which batches?) and must be carefully documented in the regulated pharmaceutical environment.  

The 6:1 ratio was as true at the Alumax plant in 1997 as it is in today’s pharmaceutical plants. 

Doyle Johnson

It’s important to note, though, that lack of PM does not immediately result in more CM – it takes time for the results to show up as increasing equipment repair needs. This is one reason that we often see under-maintained facilities. The local management can take credit for cost savings in the short term and often move on to other plants before the equipment starts breaking down, leaving a ticking time bomb for the next management group to deal with. 

Identifying the ‘Right’ Amount of PM 

An ideal approach is to apply the “right” amount of PM so that the plant continues to perform at a high level for a longer period. With this in mind, there are three areas I recommend owners consider when shaping their facility management plans: 

• Employee Morale: Often overlooked in maintenance plans, the condition of amenity areas can influence product quality by affecting the morale of those working at the plant. When they see dirty offices, unkempt lawns and potholes in the parking lot, their attitude toward product defects becomes naturally more tolerant. Staff are less likely to make improvement suggestions if it appears to them that management does not care. Pride in your workplace is always reflected in lower operating costs and higher product quality. 
• Opportunities for Failure: It is also important to identify those items that should not be maintained at all, but rather should be run to failure. Few people replace light bulbs when they think they are near the end of their life. Light bulbs are replaced when they fail. In a similar vein, some items do not gain performance by being replaced before they fail, and their failure does not impact product quality. 
• Facility Age: The age of the facility also presents special considerations. A new plant can tolerate less PM since all the equipment is new and requires years of under-maintenance before it will fail. Unfortunately, under-maintenance accelerates depreciation, so the owner is worse off but does not realize it until it is too late. 
• An older facility presents more complex problems – it may have been over- or under- maintained, and some equipment may have been replaced when it failed or when new technology was required. For these facilities, it is helpful to have an independent assessment done by a third party (not the staff that works in the plant every day). By doing so, an optimum maintenance plan, combined with a capital plan to replace the most worn-out or outdated equipment, can be implemented. 

Pharmaceutical manufacturing plants are expensive to build and expensive to maintain, but their costs pale in comparison to the value of the drug products they produce. Optimum maintenance practices can take full advantage of the value these plants can offer to the enterprise. 

Doyle Johnson is principal for science and technology within Stantec’s buildings group.