All engineers should be life cycle engineers … mindful of maintenance

Shortly after Professor Paul Mativenga opened the 32^nd CIRP Conference on Life Cycle Engineering (LCE 2025), more than 200 attendees from both academia and industry, eager to share the latest insights into sustainable products and production, listened to Professor Christoph Herrmann from TU Braunschweig. In his keynote titled “All engineers should be life cycle engineers with a mindset for absolute sustainability,” he emphasized how engineers drive truly sustainable innovations. He encapsulated the essence of his impressive presentation in a promise inspired by the Hippocratic Oath: “As engineer, I recognize my duty to consider the entire life cycle of the products or technical solutions I create. I include life cycle thinking - from raw material extraction and processing, to manufacturing, distribution, use, return, disassembly, and recycling. I strive to identify and minimize negative impacts of products and processes that I create, ensuring that impacts are not shifted within the life cycle or between environmental impact categories.”¹

The integrity of this self-understanding must be acknowledged, especially in the context of the planetary boundaries. However, a closer look reveals that while certain detailed aspects, such as the retrieval of products, are explicitly referenced, the broader field of maintenance, repair, and overhaul (MRO) is not mentioned at all. Given that the authors of the oath earlier introduced an integrated framework for life cycle engineering,² which lists service and after-sales as one of the four main activities and life cycle stages, this omission is highly surprising. Undoubtedly, MRO activities are crucial not only for extending the operational lifetime of products but also for actively reducing environmental footprint during the use stage through appropriate measures.

An examination of life cycle assessment (LCA) studies indicates that maintenance activities, if mentioned at all, are usually integrated in the use stage and rarely detailed. Only a handful of studies (e.g.,^3,4) quantify the environmental impact of components substituted during the appliance lifespan of the functional unit; findings suggest that maintenance can be significant, depending on the object of study and the considered impact categories.

As of today, there are only a few suggestions on how to incorporate maintenance into LCAs. The European Commission’s recommendation on measuring and communicating the environmental performance of products⁵ lacks clarity on this matter: on the one hand, it states that repair and maintenance are automatically part of the use stage; but on the other hand, the same document recognizes these processes as a separate stage. The amended Commission Recommendation (EU) 2021/2279 ultimately does not address the issue of maintenance at all.

Regardless of whether it is a scheduled routine activity to keep an asset in operation and prevent breakdowns or a reactive task addressing a particular issue, in both cases, resources are consumed and environmental impacts created. Considering all the measures along the value chain (e.g., use of low-impact materials, closed material cycles, efficient distribution), related to the use stage (e.g., eco-design, use of less and renewable energy), and end-of-life treatment (especially waste reduction), maintenance gains significance from an environmental perspective. We provide two recent examples that demonstrate both the environmental burden of maintenance activities and the opportunities they offer:

Even if maintenance activities are not the primary lever, intentionally getting (minor) aspects wrong does not align with the concept of absolute sustainability discussed by Herrmann et al. Suboptimal maintenance concepts and constrained product utility should be just as frustrating for (life cycle) engineers as they are for users. Sophisticated predictive maintenance and solutions that effectively facilitate the “right to repair” should be a similarly compelling challenge as implementing planned obsolescence, but without the guilty conscience.

Ultimately, the combination of the right mindset, skills, methodology, and technologies is expected to yield environmentally compatible maintenance practices. These are characterized by reduced efforts and therefore lower resource consumption and pollution while simultaneously seeking to maximize the lifetime and sustainability of the use stage. One possibility could be a computerized maintenance management system structured from an ecological perspective (using LCAs) and thus aimed at mitigating the adverse effects of the remaining useful life of products.

Corresponding author: Kai Rüdele ([email protected])