The 1st Training School of the Net4CleanAir COST Action (CA23139) took place on 9–11 February 2026 at Fundación CEAM – EUPHORE Labs in Valencia, Spain. The event brought together 20 trainees, all Young Researchers and Innovators (YRIs), for three days of intensive training, hands‑on activities, and scientific exchange focused on indoor air quality and indoor air cleaning technologies.

The Training School programme combined foundational lectures on indoor air quality and air cleaning technologies with practical sessions and real‑world case studies. Participants were introduced to the EUPHORE atmospheric simulation chamber and conducted hands‑on experiments, allowing them to directly observe and test air cleaning technologies under controlled conditions. Dedicated sessions also provided trainees with the opportunity to present their own research, fostering peer‑to‑peer learning and discussion.

A strong emphasis was placed on interaction and collaboration. Group activities, discussions with trainers, and networking moments enabled participants to exchange ideas, build confidence, and explore future research directions. The programme also included a session on project and grant development, encouraging trainees to translate scientific ideas into collaborative research proposals within and beyond the COST Action.

The impact of the Training School was strongly reflected in the feedback from participants:

“This was my first time attending a Training School, and I enjoyed this experience very much! I found it truly fulfilling as it allowed me to deepen my knowledge in the field and return home with numerous ideas for future work. Moreover, the group activities were undoubtedly enriching since they enabled us to put into practice and assimilate in real time the principles learned throughout the sessions, while fostering networking among the researchers.”

Ana Silva, LEPABE / ALiCE, Faculty of Engineering, University of Porto, Portugal

“I greatly enjoyed the Net4CleanAir Training School and found it extremely valuable for strengthening both my scientific perspective and practical skills. Beyond the lectures and discussions, what I appreciated most was seeing the real day-to-day reality of research, something that is not often shown in standard PhD training schools. I will take forward new ideas and practical tools that I can apply directly to my work on catalysis for air pollution control. In addition, meeting early-career researchers and sector experts was extremely valuable for building a strong network, exchanging perspectives and creating a solid basis for future collaborations.”

Eleonora La Greca, University of Catania & CNR‑ISMN, Italy

“Participating in the Net4CleanAir 1st Training School was a truly rewarding experience for my career development. The open discussions and interactive sessions with researchers from different backgrounds helped me feel more confident when presenting my work background and engaging in international dialogue. I am returning home with new connections and fresh ideas that I am excited to incorporate into my future research on indoor air quality and environmental monitoring applications.”

Alp Kılıç, Gebze Technical University, Türkiye

“The Net4CleanAir Training School gave me a very practical opportunity to improve my understanding of indoor air pollution through real case studies and lectures delivered by experts in the field, which was especially valuable for extending my perspective beyond my usual research framework. It also allowed me to meet many colleagues, exchange ideas, and start building collaborations that can strengthen the COST Action by combining different but highly complementary skills and expertise.”

Luca Cosentino, CNR‑ISMN, Italy

The 1st Training School marked an important milestone for Net4CleanAir, reinforcing the Action’s commitment to capacity building, knowledge exchange, and the empowerment of early career researchers. By combining scientific excellence with practical experience and networking opportunities, the Training School contributed to strengthening the European community working towards cleaner, healthier indoor air.