[version 1; peer review: 1 approved with reservations]
No competing interests were disclosed.
Following a recent keynote on life cycle engineering, a vibrant debate arose regarding the significance of maintenance for environmental footprints. It has become clear to us that this aspect is currently overlooked in broader sustainability discussions. Evidence, for example from aviation, demonstrates that maintenance activities can materially shape the environmental performance of products. In some cases, they are a significant environmental burden; in others, a powerful lever for impact reduction. Therefore, ecologically informed maintenance concepts offer opportunities to optimize the use stage. We advocate for integrating maintenance systematically into life cycle assessments and engineering decision-making to achieve more sustainable products and processes.
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:
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,
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.,
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 products
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:
Maintenance plays a particularly important role in aviation, with stringent safety requirements and the aim of continuing airworthiness of aircraft. As an example, the cleaning process of aircraft engines is designed to remove accumulated contaminants from compressor blades and other engine components.
In the case of a measuring device used in the automotive sector,
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.
No data are associated with this article.
This opinion article raises an important and timely issue: the systematic underrepresentation of maintenance, repair, and overhaul (MRO) activities in life-cycle engineering and life-cycle assessment. The authors convincingly argue that maintenance can materially influence environmental performance during the use phase, and they illustrate this through two well-chosen industrial examples from aviation and precision instrumentation. The central message—that engineers should explicitly account for maintenance when aiming for genuinely sustainable systems—is sound and aligned with ongoing discussions in the field. However, several aspects limit the article’s scientific robustness. While the topic is accurately situated within current discourse, the treatment is partial rather than comprehensive. Arguments are supported mainly by illustrative cases and policy references, without a systematic engagement with the broader LCA and life-cycle engineering literature. As a result, many claims remain plausible but insufficiently substantiated. Similarly, several factual statements are directionally correct but would benefit from stronger and more numerous citations, particularly where regulatory ambiguity and the magnitude of maintenance impacts are discussed.
To strengthen the article, the authors may clearly define key concepts such as “ecologically informed maintenance” in operational terms, provide a concise review or table summarizing existing approaches to modeling maintenance in LCA; and outline at least one concrete, generalizable framework for integrating maintenance into life-cycle assessments. Addressing these points would move the article from a compelling opinion piece to a scientifically sound and methodologically instructive contribution.
Is the topic of the opinion article discussed accurately in the context of the current literature?
Partly
Are arguments sufficiently supported by evidence from the published literature?
Partly
Are all factual statements correct and adequately supported by citations?
Partly
Are the conclusions drawn balanced and justified on the basis of the presented arguments?
Partly
Reviewer Expertise:
Sustainable manufacturing, circular economy, life cycle assessment, techno economic assessment, design of experiments
I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard, however I have significant reservations, as outlined above.