For  more than 12 years the microbiologist Guenther Gapp has been working as an independent consultant with different clients and contractors worldwide (approx. 100 assignments in Europe, USA, India, Korea, Japan and South America). In many projects he has been engaged as “Aseptic Processing Expert” in remediation of companies cited with Warning Letters, and in audits, start- up of facilities, training and remediation assignments. Guenther created a new sterile risk assessment tool (SPCRA) to identify and reduce the microbial contamination and compliance risk of sterile products, which works out well if the right people are doing the assessment. The publication of this risk assessment tool won him the 2011 PDA Journal of Pharmaceutical Science and Technology Award.

Further PDA Award received April 2022: James Agalloco Award" 2021 for the best PDA training (Aseptic Processing) in Europe. 

From June 2017- June 2023 he was member in the recognized PDA Science Advisory Board, and was Co-Chair in the PDA PTC “Isolator Technology in the Pharmaceutical Industry”, published 2020. Furthermore he was engaged in the PDA EU Annex 1 Team (team received in April 2022 the Michael S. Korczynzki Award), one of the authors of PDA TR 13 (Environmental Monitoring) and engaged in the revision of TR 22 : Aseptic Processing Simulation/ Media Fill, publication planned Q3 2025.

He was also involved in PDA TR "Points to Consider No.1 Aseptic Processing" (revised 2023).

Since 2023 he was Co-Lead of the new PDA working group "PTC 12 for RABS", published in June 2025.